text: /*!
   * Less - Leaner CSS v3.0.0-RC.2
   * http://lesscss.org
   *
   * Copyright (c) 2009-2018, Alexis Sellier <self@cloudhead.net>
   * Licensed under the Apache-2.0 License.
   *
   */
  
   /** * @license Apache-2.0
   */
  
  (function(f){if(typeof exports==="object"&&typeof module!=="undefined"){module.exports=f()}else if(typeof define==="function"&&define.amd){define([],f)}else{var g;if(typeof window!=="undefined"){g=window}else if(typeof global!=="undefined"){g=global}else if(typeof self!=="undefined"){g=self}else{g=this}g.less = f()}})(function(){var define,module,exports;return (function e(t,n,r){function s(o,u){if(!n[o]){if(!t[o]){var a=typeof require=="function"&&require;if(!u&&a)return a(o,!0);if(i)return i(o,!0);var f=new Error("Cannot find module '"+o+"'");throw f.code="MODULE_NOT_FOUND",f}var l=n[o]={exports:{}};t[o][0].call(l.exports,function(e){var n=t[o][1][e];return s(n?n:e)},l,l.exports,e,t,n,r)}return n[o].exports}var i=typeof require=="function"&&require;for(var o=0;o<r.length;o++)s(r[o]);return s})({1:[function(require,module,exports){
  var addDataAttr = require("./utils").addDataAttr,
      browser = require("./browser");
  
  module.exports = function(window, options) {
  
      // use options from the current script tag data attribues
      addDataAttr(options, browser.currentScript(window));
  
      if (options.isFileProtocol === undefined) {
          options.isFileProtocol = /^(file|(chrome|safari)(-extension)?|resource|qrc|app):/.test(window.location.protocol);
      }
  
      // Load styles asynchronously (default: false)
      //
      // This is set to `false` by default, so that the body
      // doesn't start loading before the stylesheets are parsed.
      // Setting this to `true` can result in flickering.
      //
      options.async = options.async || false;
      options.fileAsync = options.fileAsync || false;
  
      // Interval between watch polls
      options.poll = options.poll || (options.isFileProtocol ? 1000 : 1500);
  
      options.env = options.env || (window.location.hostname == '127.0.0.1' ||
          window.location.hostname == '0.0.0.0'   ||
          window.location.hostname == 'localhost' ||
          (window.location.port &&
              window.location.port.length > 0)      ||
          options.isFileProtocol                   ? 'development'
          : 'production');
  
      var dumpLineNumbers = /!dumpLineNumbers:(comments|mediaquery|all)/.exec(window.location.hash);
      if (dumpLineNumbers) {
          options.dumpLineNumbers = dumpLineNumbers[1];
      }
  
      if (options.useFileCache === undefined) {
          options.useFileCache = true;
      }
  
      if (options.onReady === undefined) {
          options.onReady = true;
      }
  
      options.javascriptEnabled = (options.javascriptEnabled || options.inlineJavaScript) ? true : false;
  
  };
  
  },{"./browser":3,"./utils":11}],2:[function(require,module,exports){
  /**
   * Kicks off less and compiles any stylesheets
   * used in the browser distributed version of less
   * to kick-start less using the browser api
   */
  /* global window, document */
  
  // TODO - consider switching this out for a recommendation for this polyfill?
  // <script src="https://cdn.polyfill.io/v2/polyfill.min.js"></script>
  // Browsers have good Promise support
  require("promise/polyfill");
  
  var options = require('../less/default-options')();
  
  if (window.less) {
      for (key in window.less) {
          if (window.less.hasOwnProperty(key)) {
              options[key] = window.less[key];
          }
      }
  }
  require("./add-default-options")(window, options);
  
  options.plugins = options.plugins || [];
  
  if (window.LESS_PLUGINS) {
      options.plugins = options.plugins.concat(window.LESS_PLUGINS);
  }
  
  var less = module.exports = require("./index")(window, options);
  
  window.less = less;
  
  var css, head, style;
  
  // Always restore page visibility
  function resolveOrReject(data) {
      if (data.filename) {
          console.warn(data);
      }
      if (!options.async) {
          head.removeChild(style);
      }
  }
  
  if (options.onReady) {
      if (/!watch/.test(window.location.hash)) {
          less.watch();
      }
      // Simulate synchronous stylesheet loading by hiding page rendering
      if (!options.async) {
          css = 'body { display: none !important }';
          head = document.head || document.getElementsByTagName('head')[0];
          style = document.createElement('style');
  
          style.type = 'text/css';
          if (style.styleSheet) {
              style.styleSheet.cssText = css;
          } else {
              style.appendChild(document.createTextNode(css));
          }
  
          head.appendChild(style);
      }
      less.registerStylesheetsImmediately();
      less.pageLoadFinished = less.refresh(less.env === 'development').then(resolveOrReject, resolveOrReject);
  }
  
  },{"../less/default-options":16,"./add-default-options":1,"./index":8,"promise/polyfill":100}],3:[function(require,module,exports){
  var utils = require("./utils");
  module.exports = {
      createCSS: function (document, styles, sheet) {
          // Strip the query-string
          var href = sheet.href || '';
  
          // If there is no title set, use the filename, minus the extension
          var id = 'less:' + (sheet.title || utils.extractId(href));
  
          // If this has already been inserted into the DOM, we may need to replace it
          var oldStyleNode = document.getElementById(id);
          var keepOldStyleNode = false;
  
          // Create a new stylesheet node for insertion or (if necessary) replacement
          var styleNode = document.createElement('style');
          styleNode.setAttribute('type', 'text/css');
          if (sheet.media) {
              styleNode.setAttribute('media', sheet.media);
          }
          styleNode.id = id;
  
          if (!styleNode.styleSheet) {
              styleNode.appendChild(document.createTextNode(styles));
  
              // If new contents match contents of oldStyleNode, don't replace oldStyleNode
              keepOldStyleNode = (oldStyleNode !== null && oldStyleNode.childNodes.length > 0 && styleNode.childNodes.length > 0 &&
                  oldStyleNode.firstChild.nodeValue === styleNode.firstChild.nodeValue);
          }
  
          var head = document.getElementsByTagName('head')[0];
  
          // If there is no oldStyleNode, just append; otherwise, only append if we need
          // to replace oldStyleNode with an updated stylesheet
          if (oldStyleNode === null || keepOldStyleNode === false) {
              var nextEl = sheet && sheet.nextSibling || null;
              if (nextEl) {
                  nextEl.parentNode.insertBefore(styleNode, nextEl);
              } else {
                  head.appendChild(styleNode);
              }
          }
          if (oldStyleNode && keepOldStyleNode === false) {
              oldStyleNode.parentNode.removeChild(oldStyleNode);
          }
  
          // For IE.
          // This needs to happen *after* the style element is added to the DOM, otherwise IE 7 and 8 may crash.
          // See http://social.msdn.microsoft.com/Forums/en-US/7e081b65-878a-4c22-8e68-c10d39c2ed32/internet-explorer-crashes-appending-style-element-to-head
          if (styleNode.styleSheet) {
              try {
                  styleNode.styleSheet.cssText = styles;
              } catch (e) {
                  throw new Error("Couldn't reassign styleSheet.cssText.");
              }
          }
      },
      currentScript: function(window) {
          var document = window.document;
          return document.currentScript || (function() {
              var scripts = document.getElementsByTagName("script");
              return scripts[scripts.length - 1];
          })();
      }
  };
  
  },{"./utils":11}],4:[function(require,module,exports){
  // Cache system is a bit outdated and could do with work
  
  module.exports = function(window, options, logger) {
      var cache = null;
      if (options.env !== 'development') {
          try {
              cache = (typeof window.localStorage === 'undefined') ? null : window.localStorage;
          } catch (_) {}
      }
      return {
          setCSS: function(path, lastModified, modifyVars, styles) {
              if (cache) {
                  logger.info('saving ' + path + ' to cache.');
                  try {
                      cache.setItem(path, styles);
                      cache.setItem(path + ':timestamp', lastModified);
                      if (modifyVars) {
                          cache.setItem(path + ':vars', JSON.stringify(modifyVars));
                      }
                  } catch (e) {
                      // TODO - could do with adding more robust error handling
                      logger.error('failed to save "' + path + '" to local storage for caching.');
                  }
              }
          },
          getCSS: function(path, webInfo, modifyVars) {
              var css       = cache && cache.getItem(path),
                  timestamp = cache && cache.getItem(path + ':timestamp'),
                  vars      = cache && cache.getItem(path + ':vars');
  
              modifyVars = modifyVars || {};
  
              if (timestamp && webInfo.lastModified &&
                  (new Date(webInfo.lastModified).valueOf() ===
                      new Date(timestamp).valueOf()) &&
                  (!modifyVars && !vars || JSON.stringify(modifyVars) === vars)) {
                  // Use local copy
                  return css;
              }
          }
      };
  };
  
  },{}],5:[function(require,module,exports){
  var utils = require("./utils"),
      browser = require("./browser");
  
  module.exports = function(window, less, options) {
  
      function errorHTML(e, rootHref) {
          var id = 'less-error-message:' + utils.extractId(rootHref || "");
          var template = '<li><label>{line}</label><pre class="{class}">{content}</pre></li>';
          var elem = window.document.createElement('div'), timer, content, errors = [];
          var filename = e.filename || rootHref;
          var filenameNoPath = filename.match(/([^\/]+(\?.*)?)$/)[1];
  
          elem.id        = id;
          elem.className = "less-error-message";
  
          content = '<h3>'  + (e.type || "Syntax") + "Error: " + (e.message || 'There is an error in your .less file') +
              '</h3>' + '<p>in <a href="' + filename   + '">' + filenameNoPath + "</a> ";
  
          var errorline = function (e, i, classname) {
              if (e.extract[i] !== undefined) {
                  errors.push(template.replace(/\{line\}/, (parseInt(e.line, 10) || 0) + (i - 1))
                      .replace(/\{class\}/, classname)
                      .replace(/\{content\}/, e.extract[i]));
              }
          };
  
          if (e.line) {
              errorline(e, 0, '');
              errorline(e, 1, 'line');
              errorline(e, 2, '');
              content += 'on line ' + e.line + ', column ' + (e.column + 1) + ':</p>' +
                  '<ul>' + errors.join('') + '</ul>';
          }
          if (e.stack && (e.extract || options.logLevel >= 4)) {
              content += '<br/>Stack Trace</br />' + e.stack.split('\n').slice(1).join('<br/>');
          }
          elem.innerHTML = content;
  
          // CSS for error messages
          browser.createCSS(window.document, [
              '.less-error-message ul, .less-error-message li {',
              'list-style-type: none;',
              'margin-right: 15px;',
              'padding: 4px 0;',
              'margin: 0;',
              '}',
              '.less-error-message label {',
              'font-size: 12px;',
              'margin-right: 15px;',
              'padding: 4px 0;',
              'color: #cc7777;',
              '}',
              '.less-error-message pre {',
              'color: #dd6666;',
              'padding: 4px 0;',
              'margin: 0;',
              'display: inline-block;',
              '}',
              '.less-error-message pre.line {',
              'color: #ff0000;',
              '}',
              '.less-error-message h3 {',
              'font-size: 20px;',
              'font-weight: bold;',
              'padding: 15px 0 5px 0;',
              'margin: 0;',
              '}',
              '.less-error-message a {',
              'color: #10a',
              '}',
              '.less-error-message .error {',
              'color: red;',
              'font-weight: bold;',
              'padding-bottom: 2px;',
              'border-bottom: 1px dashed red;',
              '}'
          ].join('\n'), { title: 'error-message' });
  
          elem.style.cssText = [
              "font-family: Arial, sans-serif",
              "border: 1px solid #e00",
              "background-color: #eee",
              "border-radius: 5px",
              "-webkit-border-radius: 5px",
              "-moz-border-radius: 5px",
              "color: #e00",
              "padding: 15px",
              "margin-bottom: 15px"
          ].join(';');
  
          if (options.env === 'development') {
              timer = setInterval(function () {
                  var document = window.document,
                      body = document.body;
                  if (body) {
                      if (document.getElementById(id)) {
                          body.replaceChild(elem, document.getElementById(id));
                      } else {
                          body.insertBefore(elem, body.firstChild);
                      }
                      clearInterval(timer);
                  }
              }, 10);
          }
      }
  
      function removeErrorHTML(path) {
          var node = window.document.getElementById('less-error-message:' + utils.extractId(path));
          if (node) {
              node.parentNode.removeChild(node);
          }
      }
  
      function removeErrorConsole(path) {
          // no action
      }
  
      function removeError(path) {
          if (!options.errorReporting || options.errorReporting === "html") {
              removeErrorHTML(path);
          } else if (options.errorReporting === "console") {
              removeErrorConsole(path);
          } else if (typeof options.errorReporting === 'function') {
              options.errorReporting("remove", path);
          }
      }
  
      function errorConsole(e, rootHref) {
          var template = '{line} {content}';
          var filename = e.filename || rootHref;
          var errors = [];
          var content = (e.type || "Syntax") + "Error: " + (e.message || 'There is an error in your .less file') +
              " in " + filename;
  
          var errorline = function (e, i, classname) {
              if (e.extract[i] !== undefined) {
                  errors.push(template.replace(/\{line\}/, (parseInt(e.line, 10) || 0) + (i - 1))
                      .replace(/\{class\}/, classname)
                      .replace(/\{content\}/, e.extract[i]));
              }
          };
  
          if (e.line) {
              errorline(e, 0, '');
              errorline(e, 1, 'line');
              errorline(e, 2, '');
              content += ' on line ' + e.line + ', column ' + (e.column + 1) + ':\n' +
                  errors.join('\n');
          }
          if (e.stack && (e.extract || options.logLevel >= 4)) {
              content += '\nStack Trace\n' + e.stack;
          }
          less.logger.error(content);
      }
  
      function error(e, rootHref) {
          if (!options.errorReporting || options.errorReporting === "html") {
              errorHTML(e, rootHref);
          } else if (options.errorReporting === "console") {
              errorConsole(e, rootHref);
          } else if (typeof options.errorReporting === 'function') {
              options.errorReporting("add", e, rootHref);
          }
      }
  
      return {
          add: error,
          remove: removeError
      };
  };
  
  },{"./browser":3,"./utils":11}],6:[function(require,module,exports){
  /* global window, XMLHttpRequest */
  
  module.exports = function(options, logger) {
  
      var AbstractFileManager = require("../less/environment/abstract-file-manager.js");
  
      var fileCache = {};
  
      // TODOS - move log somewhere. pathDiff and doing something similar in node. use pathDiff in the other browser file for the initial load
      var FileManager = function() {
      };
  
      FileManager.prototype = new AbstractFileManager();
  
      FileManager.prototype.alwaysMakePathsAbsolute = function alwaysMakePathsAbsolute() {
          return true;
      };
      FileManager.prototype.join = function join(basePath, laterPath) {
          if (!basePath) {
              return laterPath;
          }
          return this.extractUrlParts(laterPath, basePath).path;
      };
      FileManager.prototype.doXHR = function doXHR(url, type, callback, errback) {
  
          var xhr = new XMLHttpRequest();
          var async = options.isFileProtocol ? options.fileAsync : true;
  
          if (typeof xhr.overrideMimeType === 'function') {
              xhr.overrideMimeType('text/css');
          }
          logger.debug("XHR: Getting '" + url + "'");
          xhr.open('GET', url, async);
          xhr.setRequestHeader('Accept', type || 'text/x-less, text/css; q=0.9, */*; q=0.5');
          xhr.send(null);
  
          function handleResponse(xhr, callback, errback) {
              if (xhr.status >= 200 && xhr.status < 300) {
                  callback(xhr.responseText,
                      xhr.getResponseHeader("Last-Modified"));
              } else if (typeof errback === 'function') {
                  errback(xhr.status, url);
              }
          }
  
          if (options.isFileProtocol && !options.fileAsync) {
              if (xhr.status === 0 || (xhr.status >= 200 && xhr.status < 300)) {
                  callback(xhr.responseText);
              } else {
                  errback(xhr.status, url);
              }
          } else if (async) {
              xhr.onreadystatechange = function () {
                  if (xhr.readyState == 4) {
                      handleResponse(xhr, callback, errback);
                  }
              };
          } else {
              handleResponse(xhr, callback, errback);
          }
      };
      FileManager.prototype.supports = function(filename, currentDirectory, options, environment) {
          return true;
      };
  
      FileManager.prototype.clearFileCache = function() {
          fileCache = {};
      };
  
      FileManager.prototype.loadFile = function loadFile(filename, currentDirectory, options, environment) {
          // TODO: Add prefix support like less-node?
          // What about multiple paths?
  
          if (currentDirectory && !this.isPathAbsolute(filename)) {
              filename = currentDirectory + filename;
          }
  
          filename = options.ext ? this.tryAppendExtension(filename, options.ext) : filename;
  
          options = options || {};
  
          // sheet may be set to the stylesheet for the initial load or a collection of properties including
          // some context variables for imports
          var hrefParts = this.extractUrlParts(filename, window.location.href);
          var href      = hrefParts.url;
          var self      = this;
          
          return new Promise(function(resolve, reject) {
              if (options.useFileCache && fileCache[href]) {
                  try {
                      var lessText = fileCache[href];
                      return resolve({ contents: lessText, filename: href, webInfo: { lastModified: new Date() }});
                  } catch (e) {
                      return reject({ filename: href, message: "Error loading file " + href + " error was " + e.message });
                  }
              }
  
              self.doXHR(href, options.mime, function doXHRCallback(data, lastModified) {
                  // per file cache
                  fileCache[href] = data;
  
                  // Use remote copy (re-parse)
                  resolve({ contents: data, filename: href, webInfo: { lastModified: lastModified }});
              }, function doXHRError(status, url) {
                  reject({ type: 'File', message: "'" + url + "' wasn't found (" + status + ")", href: href });
              });
          });
      };
  
      return FileManager;
  };
  
  },{"../less/environment/abstract-file-manager.js":17}],7:[function(require,module,exports){
  module.exports = function() {
  
      var functionRegistry = require("./../less/functions/function-registry");
  
      function imageSize() {
          throw {
              type: "Runtime",
              message: "Image size functions are not supported in browser version of less"
          };
      }
  
      var imageFunctions = {
          "image-size": function(filePathNode) {
              imageSize(this, filePathNode);
              return -1;
          },
          "image-width": function(filePathNode) {
              imageSize(this, filePathNode);
              return -1;
          },
          "image-height": function(filePathNode) {
              imageSize(this, filePathNode);
              return -1;
          }
      };
  
      functionRegistry.addMultiple(imageFunctions);
  };
  
  },{"./../less/functions/function-registry":26}],8:[function(require,module,exports){
  //
  // index.js
  // Should expose the additional browser functions on to the less object
  //
  var addDataAttr = require("./utils").addDataAttr,
      browser = require("./browser");
  
  module.exports = function(window, options) {
      var document = window.document;
      var less = require('../less')();
      
      less.options = options;
      var environment = less.environment,
          FileManager = require("./file-manager")(options, less.logger),
          fileManager = new FileManager();
      environment.addFileManager(fileManager);
      less.FileManager = FileManager;
      less.PluginLoader = require("./plugin-loader");
  
      require("./log-listener")(less, options);
      var errors = require("./error-reporting")(window, less, options);
      var cache = less.cache = options.cache || require("./cache")(window, options, less.logger);
      require('./image-size')(less.environment);
  
      // Setup user functions - Deprecate?
      if (options.functions) {
          less.functions.functionRegistry.addMultiple(options.functions);
      }
  
      var typePattern = /^text\/(x-)?less$/;
  
      function clone(obj) {
          return JSON.parse(JSON.stringify(obj || {}));
      }
  
      // only really needed for phantom
      function bind(func, thisArg) {
          var curryArgs = Array.prototype.slice.call(arguments, 2);
          return function() {
              var args = curryArgs.concat(Array.prototype.slice.call(arguments, 0));
              return func.apply(thisArg, args);
          };
      }
  
      function loadStyles(modifyVars) {
          var styles = document.getElementsByTagName('style'),
              style;
  
          for (var i = 0; i < styles.length; i++) {
              style = styles[i];
              if (style.type.match(typePattern)) {
                  var instanceOptions = clone(options);
                  instanceOptions.modifyVars = modifyVars;
                  var lessText = style.innerHTML || '';
                  instanceOptions.filename = document.location.href.replace(/#.*$/, '');
  
                  /* jshint loopfunc:true */
                  // use closure to store current style
                  less.render(lessText, instanceOptions,
                          bind(function(style, e, result) {
                              if (e) {
                                  errors.add(e, "inline");
                              } else {
                                  style.type = 'text/css';
                                  if (style.styleSheet) {
                                      style.styleSheet.cssText = result.css;
                                  } else {
                                      style.innerHTML = result.css;
                                  }
                              }
                          }, null, style));
              }
          }
      }
  
      function loadStyleSheet(sheet, callback, reload, remaining, modifyVars) {
  
          var instanceOptions = clone(options);
          addDataAttr(instanceOptions, sheet);
          instanceOptions.mime = sheet.type;
  
          if (modifyVars) {
              instanceOptions.modifyVars = modifyVars;
          }
  
          function loadInitialFileCallback(loadedFile) {
  
              var data = loadedFile.contents,
                  path = loadedFile.filename,
                  webInfo = loadedFile.webInfo;
  
              var newFileInfo = {
                  currentDirectory: fileManager.getPath(path),
                  filename: path,
                  rootFilename: path,
                  relativeUrls: instanceOptions.relativeUrls};
  
              newFileInfo.entryPath = newFileInfo.currentDirectory;
              newFileInfo.rootpath = instanceOptions.rootpath || newFileInfo.currentDirectory;
  
              if (webInfo) {
                  webInfo.remaining = remaining;
  
                  var css = cache.getCSS(path, webInfo, instanceOptions.modifyVars);
                  if (!reload && css) {
                      webInfo.local = true;
                      callback(null, css, data, sheet, webInfo, path);
                      return;
                  }
  
              }
  
              // TODO add tests around how this behaves when reloading
              errors.remove(path);
  
              instanceOptions.rootFileInfo = newFileInfo;
              less.render(data, instanceOptions, function(e, result) {
                  if (e) {
                      e.href = path;
                      callback(e);
                  } else {
                      cache.setCSS(sheet.href, webInfo.lastModified, instanceOptions.modifyVars, result.css);
                      callback(null, result.css, data, sheet, webInfo, path);
                  }
              });
          }
  
          fileManager.loadFile(sheet.href, null, instanceOptions, environment)
              .then(function(loadedFile) {
                  loadInitialFileCallback(loadedFile);
              }).catch(function(err) {
                  console.log(err);
                  callback(err);
              });
  
      }
  
      function loadStyleSheets(callback, reload, modifyVars) {
          for (var i = 0; i < less.sheets.length; i++) {
              loadStyleSheet(less.sheets[i], callback, reload, less.sheets.length - (i + 1), modifyVars);
          }
      }
  
      function initRunningMode() {
          if (less.env === 'development') {
              less.watchTimer = setInterval(function () {
                  if (less.watchMode) {
                      fileManager.clearFileCache();
                      loadStyleSheets(function (e, css, _, sheet, webInfo) {
                          if (e) {
                              errors.add(e, e.href || sheet.href);
                          } else if (css) {
                              browser.createCSS(window.document, css, sheet);
                          }
                      });
                  }
              }, options.poll);
          }
      }
  
      //
      // Watch mode
      //
      less.watch   = function () {
          if (!less.watchMode ) {
              less.env = 'development';
              initRunningMode();
          }
          this.watchMode = true;
          return true;
      };
  
      less.unwatch = function () {clearInterval(less.watchTimer); this.watchMode = false; return false; };
  
      //
      // Synchronously get all <link> tags with the 'rel' attribute set to
      // "stylesheet/less".
      //
      less.registerStylesheetsImmediately = function() {
          var links = document.getElementsByTagName('link');
          less.sheets = [];
  
          for (var i = 0; i < links.length; i++) {
              if (links[i].rel === 'stylesheet/less' || (links[i].rel.match(/stylesheet/) &&
                  (links[i].type.match(typePattern)))) {
                  less.sheets.push(links[i]);
              }
          }
      };
  
      //
      // Asynchronously get all <link> tags with the 'rel' attribute set to
      // "stylesheet/less", returning a Promise.
      //
      less.registerStylesheets = function() {
          return new Promise(function(resolve, reject) {
              less.registerStylesheetsImmediately();
              resolve();
          });
      };
  
      //
      // With this function, it's possible to alter variables and re-render
      // CSS without reloading less-files
      //
      less.modifyVars = function(record) {
          return less.refresh(true, record, false);
      };
  
      less.refresh = function (reload, modifyVars, clearFileCache) {
          if ((reload || clearFileCache) && clearFileCache !== false) {
              fileManager.clearFileCache();
          }
          return new Promise(function (resolve, reject) {
              var startTime, endTime, totalMilliseconds, remainingSheets;
              startTime = endTime = new Date();
  
              // Set counter for remaining unprocessed sheets
              remainingSheets = less.sheets.length;
  
              if (remainingSheets === 0) {
  
                  endTime = new Date();
                  totalMilliseconds = endTime - startTime;
                  less.logger.info("Less has finished and no sheets were loaded.");
                  resolve({
                      startTime: startTime,
                      endTime: endTime,
                      totalMilliseconds: totalMilliseconds,
                      sheets: less.sheets.length
                  });
  
              } else {
                  // Relies on less.sheets array, callback seems to be guaranteed to be called for every element of the array
                  loadStyleSheets(function (e, css, _, sheet, webInfo) {
                      if (e) {
                          errors.add(e, e.href || sheet.href);
                          reject(e);
                          return;
                      }
                      if (webInfo.local) {
                          less.logger.info("Loading " + sheet.href + " from cache.");
                      } else {
                          less.logger.info("Rendered " + sheet.href + " successfully.");
                      }
                      browser.createCSS(window.document, css, sheet);
                      less.logger.info("CSS for " + sheet.href + " generated in " + (new Date() - endTime) + 'ms');
  
                      // Count completed sheet
                      remainingSheets--;
  
                      // Check if the last remaining sheet was processed and then call the promise
                      if (remainingSheets === 0) {
                          totalMilliseconds = new Date() - startTime;
                          less.logger.info("Less has finished. CSS generated in " + totalMilliseconds + 'ms');
                          resolve({
                              startTime: startTime,
                              endTime: endTime,
                              totalMilliseconds: totalMilliseconds,
                              sheets: less.sheets.length
                          });
                      }
                      endTime = new Date();
                  }, reload, modifyVars);
              }
  
              loadStyles(modifyVars);
          });
      };
  
      less.refreshStyles = loadStyles;
      return less;
  };
  
  },{"../less":35,"./browser":3,"./cache":4,"./error-reporting":5,"./file-manager":6,"./image-size":7,"./log-listener":9,"./plugin-loader":10,"./utils":11}],9:[function(require,module,exports){
  module.exports = function(less, options) {
  
      var logLevel_debug = 4,
          logLevel_info = 3,
          logLevel_warn = 2,
          logLevel_error = 1;
  
      // The amount of logging in the javascript console.
      // 3 - Debug, information and errors
      // 2 - Information and errors
      // 1 - Errors
      // 0 - None
      // Defaults to 2
      options.logLevel = typeof options.logLevel !== 'undefined' ? options.logLevel : (options.env === 'development' ?  logLevel_info : logLevel_error);
  
      if (!options.loggers) {
          options.loggers = [{
              debug: function(msg) {
                  if (options.logLevel >= logLevel_debug) {
                      console.log(msg);
                  }
              },
              info: function(msg) {
                  if (options.logLevel >= logLevel_info) {
                      console.log(msg);
                  }
              },
              warn: function(msg) {
                  if (options.logLevel >= logLevel_warn) {
                      console.warn(msg);
                  }
              },
              error: function(msg) {
                  if (options.logLevel >= logLevel_error) {
                      console.error(msg);
                  }
              }
          }];
      }
      for (var i = 0; i < options.loggers.length; i++) {
          less.logger.addListener(options.loggers[i]);
      }
  };
  
  },{}],10:[function(require,module,exports){
  // TODO: Add tests for browser @plugin
  /*global window */
  
  var AbstractPluginLoader = require("../less/environment/abstract-plugin-loader.js");
  
  /**
   * Browser Plugin Loader
   */
  var PluginLoader = function(less) {
      this.less = less;
      // shim for browser require?
      this.require = require;
  };
  
  PluginLoader.prototype = new AbstractPluginLoader();
  
  PluginLoader.prototype.loadPlugin = function(filename, basePath, context, environment, fileManager) {
      return new Promise(function(fulfill, reject) {
          fileManager.loadFile(filename, basePath, context, environment)
              .then(fulfill).catch(reject);
      });        
  };
  
  module.exports = PluginLoader;
  
  
  },{"../less/environment/abstract-plugin-loader.js":18}],11:[function(require,module,exports){
  module.exports = {
      extractId: function(href) {
          return href.replace(/^[a-z-]+:\/+?[^\/]+/, '')  // Remove protocol & domain
              .replace(/[\?\&]livereload=\w+/, '')        // Remove LiveReload cachebuster
              .replace(/^\//, '')                         // Remove root /
              .replace(/\.[a-zA-Z]+$/, '')                // Remove simple extension
              .replace(/[^\.\w-]+/g, '-')                 // Replace illegal characters
              .replace(/\./g, ':');                       // Replace dots with colons(for valid id)
      },
      addDataAttr: function(options, tag) {
          for (var opt in tag.dataset) {
              if (tag.dataset.hasOwnProperty(opt)) {
                  if (opt === "env" || opt === "dumpLineNumbers" || opt === "rootpath" || opt === "errorReporting") {
                      options[opt] = tag.dataset[opt];
                  } else {
                      try {
                          options[opt] = JSON.parse(tag.dataset[opt]);
                      }
                      catch (_) {}
                  }
              }
          }
      }
  };
  
  },{}],12:[function(require,module,exports){
  var contexts = {};
  module.exports = contexts;
  
  var copyFromOriginal = function copyFromOriginal(original, destination, propertiesToCopy) {
      if (!original) { return; }
  
      for (var i = 0; i < propertiesToCopy.length; i++) {
          if (original.hasOwnProperty(propertiesToCopy[i])) {
              destination[propertiesToCopy[i]] = original[propertiesToCopy[i]];
          }
      }
  };
  
  /*
   parse is used whilst parsing
   */
  var parseCopyProperties = [
      // options
      'paths',            // option - unmodified - paths to search for imports on
      'relativeUrls',     // option - whether to adjust URL's to be relative
      'rootpath',         // option - rootpath to append to URL's
      'strictImports',    // option -
      'insecure',         // option - whether to allow imports from insecure ssl hosts
      'dumpLineNumbers',  // option - whether to dump line numbers
      'compress',         // option - whether to compress
      'syncImport',       // option - whether to import synchronously
      'chunkInput',       // option - whether to chunk input. more performant but causes parse issues.
      'mime',             // browser only - mime type for sheet import
      'useFileCache',     // browser only - whether to use the per file session cache
      // context
      'processImports',   // option & context - whether to process imports. if false then imports will not be imported.
                          // Used by the import manager to stop multiple import visitors being created.
      'pluginManager'     // Used as the plugin manager for the session
  ];
  
  contexts.Parse = function(options) {
      copyFromOriginal(options, this, parseCopyProperties);
  
      if (typeof this.paths === "string") { this.paths = [this.paths]; }
  };
  
  var evalCopyProperties = [
      'paths',             // additional include paths
      'compress',          // whether to compress
      'ieCompat',          // whether to enforce IE compatibility (IE8 data-uri)
      'strictMath',        // whether math has to be within parenthesis
      'strictUnits',       // whether units need to evaluate correctly
      'sourceMap',         // whether to output a source map
      'importMultiple',    // whether we are currently importing multiple copies
      'urlArgs',           // whether to add args into url tokens
      'javascriptEnabled', // option - whether Inline JavaScript is enabled. if undefined, defaults to false
      'pluginManager',     // Used as the plugin manager for the session
      'importantScope'     // used to bubble up !important statements
  ];
  
  contexts.Eval = function(options, frames) {
      copyFromOriginal(options, this, evalCopyProperties);
  
      if (typeof this.paths === "string") { this.paths = [this.paths]; }
  
      this.frames = frames || [];
      this.importantScope = this.importantScope || [];
  };
  
  contexts.Eval.prototype.inParenthesis = function () {
      if (!this.parensStack) {
          this.parensStack = [];
      }
      this.parensStack.push(true);
  };
  
  contexts.Eval.prototype.outOfParenthesis = function () {
      this.parensStack.pop();
  };
  
  contexts.Eval.prototype.mathOn = true;
  contexts.Eval.prototype.isMathOn = function () {
      if (!this.mathOn) {
          return false;
      }
      return this.strictMath ? (this.parensStack && this.parensStack.length) : true;
  };
  
  contexts.Eval.prototype.isPathRelative = function (path) {
      return !/^(?:[a-z-]+:|\/|#)/i.test(path);
  };
  
  contexts.Eval.prototype.normalizePath = function( path ) {
      var
          segments = path.split("/").reverse(),
          segment;
  
      path = [];
      while (segments.length !== 0 ) {
          segment = segments.pop();
          switch ( segment ) {
              case ".":
                  break;
              case "..":
                  if ((path.length === 0) || (path[path.length - 1] === "..")) {
                      path.push( segment );
                  } else {
                      path.pop();
                  }
                  break;
              default:
                  path.push( segment );
                  break;
          }
      }
  
      return path.join("/");
  };
  
  // todo - do the same for the toCSS ?
  
  },{}],13:[function(require,module,exports){
  module.exports = {
      'aliceblue':'#f0f8ff',
      'antiquewhite':'#faebd7',
      'aqua':'#00ffff',
      'aquamarine':'#7fffd4',
      'azure':'#f0ffff',
      'beige':'#f5f5dc',
      'bisque':'#ffe4c4',
      'black':'#000000',
      'blanchedalmond':'#ffebcd',
      'blue':'#0000ff',
      'blueviolet':'#8a2be2',
      'brown':'#a52a2a',
      'burlywood':'#deb887',
      'cadetblue':'#5f9ea0',
      'chartreuse':'#7fff00',
      'chocolate':'#d2691e',
      'coral':'#ff7f50',
      'cornflowerblue':'#6495ed',
      'cornsilk':'#fff8dc',
      'crimson':'#dc143c',
      'cyan':'#00ffff',
      'darkblue':'#00008b',
      'darkcyan':'#008b8b',
      'darkgoldenrod':'#b8860b',
      'darkgray':'#a9a9a9',
      'darkgrey':'#a9a9a9',
      'darkgreen':'#006400',
      'darkkhaki':'#bdb76b',
      'darkmagenta':'#8b008b',
      'darkolivegreen':'#556b2f',
      'darkorange':'#ff8c00',
      'darkorchid':'#9932cc',
      'darkred':'#8b0000',
      'darksalmon':'#e9967a',
      'darkseagreen':'#8fbc8f',
      'darkslateblue':'#483d8b',
      'darkslategray':'#2f4f4f',
      'darkslategrey':'#2f4f4f',
      'darkturquoise':'#00ced1',
      'darkviolet':'#9400d3',
      'deeppink':'#ff1493',
      'deepskyblue':'#00bfff',
      'dimgray':'#696969',
      'dimgrey':'#696969',
      'dodgerblue':'#1e90ff',
      'firebrick':'#b22222',
      'floralwhite':'#fffaf0',
      'forestgreen':'#228b22',
      'fuchsia':'#ff00ff',
      'gainsboro':'#dcdcdc',
      'ghostwhite':'#f8f8ff',
      'gold':'#ffd700',
      'goldenrod':'#daa520',
      'gray':'#808080',
      'grey':'#808080',
      'green':'#008000',
      'greenyellow':'#adff2f',
      'honeydew':'#f0fff0',
      'hotpink':'#ff69b4',
      'indianred':'#cd5c5c',
      'indigo':'#4b0082',
      'ivory':'#fffff0',
      'khaki':'#f0e68c',
      'lavender':'#e6e6fa',
      'lavenderblush':'#fff0f5',
      'lawngreen':'#7cfc00',
      'lemonchiffon':'#fffacd',
      'lightblue':'#add8e6',
      'lightcoral':'#f08080',
      'lightcyan':'#e0ffff',
      'lightgoldenrodyellow':'#fafad2',
      'lightgray':'#d3d3d3',
      'lightgrey':'#d3d3d3',
      'lightgreen':'#90ee90',
      'lightpink':'#ffb6c1',
      'lightsalmon':'#ffa07a',
      'lightseagreen':'#20b2aa',
      'lightskyblue':'#87cefa',
      'lightslategray':'#778899',
      'lightslategrey':'#778899',
      'lightsteelblue':'#b0c4de',
      'lightyellow':'#ffffe0',
      'lime':'#00ff00',
      'limegreen':'#32cd32',
      'linen':'#faf0e6',
      'magenta':'#ff00ff',
      'maroon':'#800000',
      'mediumaquamarine':'#66cdaa',
      'mediumblue':'#0000cd',
      'mediumorchid':'#ba55d3',
      'mediumpurple':'#9370d8',
      'mediumseagreen':'#3cb371',
      'mediumslateblue':'#7b68ee',
      'mediumspringgreen':'#00fa9a',
      'mediumturquoise':'#48d1cc',
      'mediumvioletred':'#c71585',
      'midnightblue':'#191970',
      'mintcream':'#f5fffa',
      'mistyrose':'#ffe4e1',
      'moccasin':'#ffe4b5',
      'navajowhite':'#ffdead',
      'navy':'#000080',
      'oldlace':'#fdf5e6',
      'olive':'#808000',
      'olivedrab':'#6b8e23',
      'orange':'#ffa500',
      'orangered':'#ff4500',
      'orchid':'#da70d6',
      'palegoldenrod':'#eee8aa',
      'palegreen':'#98fb98',
      'paleturquoise':'#afeeee',
      'palevioletred':'#d87093',
      'papayawhip':'#ffefd5',
      'peachpuff':'#ffdab9',
      'peru':'#cd853f',
      'pink':'#ffc0cb',
      'plum':'#dda0dd',
      'powderblue':'#b0e0e6',
      'purple':'#800080',
      'rebeccapurple':'#663399',
      'red':'#ff0000',
      'rosybrown':'#bc8f8f',
      'royalblue':'#4169e1',
      'saddlebrown':'#8b4513',
      'salmon':'#fa8072',
      'sandybrown':'#f4a460',
      'seagreen':'#2e8b57',
      'seashell':'#fff5ee',
      'sienna':'#a0522d',
      'silver':'#c0c0c0',
      'skyblue':'#87ceeb',
      'slateblue':'#6a5acd',
      'slategray':'#708090',
      'slategrey':'#708090',
      'snow':'#fffafa',
      'springgreen':'#00ff7f',
      'steelblue':'#4682b4',
      'tan':'#d2b48c',
      'teal':'#008080',
      'thistle':'#d8bfd8',
      'tomato':'#ff6347',
      'turquoise':'#40e0d0',
      'violet':'#ee82ee',
      'wheat':'#f5deb3',
      'white':'#ffffff',
      'whitesmoke':'#f5f5f5',
      'yellow':'#ffff00',
      'yellowgreen':'#9acd32'
  };
  },{}],14:[function(require,module,exports){
  module.exports = {
      colors: require("./colors"),
      unitConversions: require("./unit-conversions")
  };
  
  },{"./colors":13,"./unit-conversions":15}],15:[function(require,module,exports){
  module.exports = {
      length: {
          'm': 1,
          'cm': 0.01,
          'mm': 0.001,
          'in': 0.0254,
          'px': 0.0254 / 96,
          'pt': 0.0254 / 72,
          'pc': 0.0254 / 72 * 12
      },
      duration: {
          's': 1,
          'ms': 0.001
      },
      angle: {
          'rad': 1 / (2 * Math.PI),
          'deg': 1 / 360,
          'grad': 1 / 400,
          'turn': 1
      }
  };
  },{}],16:[function(require,module,exports){
  // Export a new default each time
  module.exports = function() {
      return {
          /* Outputs a makefile import dependency list to stdout. */
          depends: false,
  
          /* Compress using less built-in compression. 
           * This does an okay job but does not utilise all the tricks of 
           * dedicated css compression. */
          compress: false,
  
          /* Runs the less parser and just reports errors without any output. */
          lint: false,
  
          /* Sets available include paths.
           * If the file in an @import rule does not exist at that exact location, 
           * less will look for it at the location(s) passed to this option. 
           * You might use this for instance to specify a path to a library which 
           * you want to be referenced simply and relatively in the less files. */
          paths: [],
  
          /* color output in the terminal */
          color: true,
  
          /* The strictImports controls whether the compiler will allow an @import inside of either 
           * @media blocks or (a later addition) other selector blocks.
           * See: https://github.com/less/less.js/issues/656 */
          strictImports: false,
  
          /* Allow Imports from Insecure HTTPS Hosts */
          insecure: false,
  
          /* Allows you to add a path to every generated import and url in your css. 
           * This does not affect less import statements that are processed, just ones 
           * that are left in the output css. */
          rootpath: '',
  
          /* By default URLs are kept as-is, so if you import a file in a sub-directory 
           * that references an image, exactly the same URL will be output in the css. 
           * This option allows you to re-write URL's in imported files so that the 
           * URL is always relative to the base imported file */
          relativeUrls: false,
  
          /* Compatibility with IE8. Used for limiting data-uri length */
          ieCompat: false,  // true until 3.0
  
          /* Without this option on, Less will try and process all math in your css */
          strictMath: false,
  
          /* Without this option, less attempts to guess at the output unit when it does maths. */
          strictUnits: false,
  
          /* Effectively the declaration is put at the top of your base Less file, 
           * meaning it can be used but it also can be overridden if this variable 
           * is defined in the file. */
          globalVars: null,
  
          /* As opposed to the global variable option, this puts the declaration at the
           * end of your base file, meaning it will override anything defined in your Less file. */
          modifyVars: null,
  
          /* This option allows you to specify a argument to go on to every URL.  */
          urlArgs: ''
      }
  }
  },{}],17:[function(require,module,exports){
  var abstractFileManager = function() {
  };
  
  abstractFileManager.prototype.getPath = function (filename) {
      var j = filename.lastIndexOf('?');
      if (j > 0) {
          filename = filename.slice(0, j);
      }
      j = filename.lastIndexOf('/');
      if (j < 0) {
          j = filename.lastIndexOf('\\');
      }
      if (j < 0) {
          return "";
      }
      return filename.slice(0, j + 1);
  };
  
  abstractFileManager.prototype.tryAppendExtension = function(path, ext) {
      return /(\.[a-z]*$)|([\?;].*)$/.test(path) ? path : path + ext;
  };
  
  abstractFileManager.prototype.tryAppendLessExtension = function(path) {
      return this.tryAppendExtension(path, '.less');
  };
  
  abstractFileManager.prototype.supportsSync = function() {
      return false;
  };
  
  abstractFileManager.prototype.alwaysMakePathsAbsolute = function() {
      return false;
  };
  
  abstractFileManager.prototype.isPathAbsolute = function(filename) {
      return (/^(?:[a-z-]+:|\/|\\|#)/i).test(filename);
  };
  // TODO: pull out / replace?
  abstractFileManager.prototype.join = function(basePath, laterPath) {
      if (!basePath) {
          return laterPath;
      }
      return basePath + laterPath;
  };
  
  abstractFileManager.prototype.pathDiff = function pathDiff(url, baseUrl) {
      // diff between two paths to create a relative path
  
      var urlParts = this.extractUrlParts(url),
          baseUrlParts = this.extractUrlParts(baseUrl),
          i, max, urlDirectories, baseUrlDirectories, diff = "";
      if (urlParts.hostPart !== baseUrlParts.hostPart) {
          return "";
      }
      max = Math.max(baseUrlParts.directories.length, urlParts.directories.length);
      for (i = 0; i < max; i++) {
          if (baseUrlParts.directories[i] !== urlParts.directories[i]) { break; }
      }
      baseUrlDirectories = baseUrlParts.directories.slice(i);
      urlDirectories = urlParts.directories.slice(i);
      for (i = 0; i < baseUrlDirectories.length - 1; i++) {
          diff += "../";
      }
      for (i = 0; i < urlDirectories.length - 1; i++) {
          diff += urlDirectories[i] + "/";
      }
      return diff;
  };
  // helper function, not part of API
  abstractFileManager.prototype.extractUrlParts = function extractUrlParts(url, baseUrl) {
      // urlParts[1] = protocol://hostname/ OR /
      // urlParts[2] = / if path relative to host base
      // urlParts[3] = directories
      // urlParts[4] = filename
      // urlParts[5] = parameters
  
      var urlPartsRegex = /^((?:[a-z-]+:)?\/{2}(?:[^\/\?#]*\/)|([\/\\]))?((?:[^\/\\\?#]*[\/\\])*)([^\/\\\?#]*)([#\?].*)?$/i,
          urlParts = url.match(urlPartsRegex),
          returner = {}, rawDirectories = [], directories = [], i, baseUrlParts;
  
      if (!urlParts) {
          throw new Error("Could not parse sheet href - '" + url + "'");
      }
  
      // Stylesheets in IE don't always return the full path
      if (baseUrl && (!urlParts[1] || urlParts[2])) {
          baseUrlParts = baseUrl.match(urlPartsRegex);
          if (!baseUrlParts) {
              throw new Error("Could not parse page url - '" + baseUrl + "'");
          }
          urlParts[1] = urlParts[1] || baseUrlParts[1] || "";
          if (!urlParts[2]) {
              urlParts[3] = baseUrlParts[3] + urlParts[3];
          }
      }
  
      if (urlParts[3]) {
          rawDirectories = urlParts[3].replace(/\\/g, "/").split("/");
  
          // collapse '..' and skip '.'
          for (i = 0; i < rawDirectories.length; i++) {
  
              if (rawDirectories[i] === "..") {
                  directories.pop();
              }
              else if (rawDirectories[i] !== ".") {
                  directories.push(rawDirectories[i]);
              }
          
          }
      }
  
      returner.hostPart = urlParts[1];
      returner.directories = directories;
      returner.rawPath = (urlParts[1] || "") + rawDirectories.join("/");
      returner.path = (urlParts[1] || "") + directories.join("/");
      returner.filename = urlParts[4];
      returner.fileUrl = returner.path + (urlParts[4] || "");
      returner.url = returner.fileUrl + (urlParts[5] || "");
      return returner;
  };
  
  module.exports = abstractFileManager;
  
  },{}],18:[function(require,module,exports){
  var functionRegistry = require("../functions/function-registry"),
      LessError = require('../less-error');
  
  var AbstractPluginLoader = function() {
  };
  
  function error(msg, type) {
      throw new LessError(
          {
              type: type || 'Syntax',
              message: msg
          }
      );
  }
  AbstractPluginLoader.prototype.evalPlugin = function(contents, context, imports, pluginOptions, fileInfo) {
  
      var loader,
          registry,
          pluginObj,
          localModule,
          pluginManager,
          filename;
  
      pluginManager = context.pluginManager;
  
      if (fileInfo) {
          if (typeof fileInfo === "string") {
              filename = fileInfo;
          }
          else {
              filename = fileInfo.filename;
          }
      }
      var shortname = (new this.less.FileManager()).extractUrlParts(filename).filename;
  
      if (filename) {
          pluginObj = pluginManager.get(filename);
  
          if (pluginObj) {
              this.trySetOptions(pluginObj, filename, shortname, pluginOptions);
              try {
                  if (pluginObj.use) {
                      pluginObj.use.call(this.context, pluginObj);
                  }
              }
              catch (e) {
                  e.message = 'Error during @plugin call';
                  return new this.less.LessError(e, imports, filename);
              }
              return pluginObj;
          }
      }
      localModule = {
          exports: {},
          pluginManager: pluginManager,
          fileInfo: fileInfo
      };
      registry = functionRegistry.create();
      
      var registerPlugin = function(obj) {
          pluginObj = obj;
      };
  
      try {
          loader = new Function("module", "require", "registerPlugin", "functions", "tree", "less", "fileInfo", contents);
          loader(localModule, this.require, registerPlugin, registry, this.less.tree, this.less, fileInfo);
      } catch (e) {
          return new this.less.LessError(e, imports, filename);
      }
        
      if (!pluginObj) {
          pluginObj = localModule.exports;
      }
      pluginObj = this.validatePlugin(pluginObj, filename, shortname);
  
      if (pluginObj) {
          // Run on first load
          pluginManager.addPlugin(pluginObj, fileInfo.filename, registry);
          pluginObj.functions = registry.getLocalFunctions();
          pluginObj.imports = imports;
          pluginObj.filename = filename;
  
          this.trySetOptions(pluginObj, filename, shortname, pluginOptions);
  
          // Run every @plugin call
          try {
              if (pluginObj.use) {
                  pluginObj.use.call(this.context, pluginObj);
              }
          }
          catch (e) {
              e.message = 'Error during @plugin call';
              return new this.less.LessError(e, imports, filename);
          }
          
      }
      else {
          return new this.less.LessError({ message: "Not a valid plugin" });
      }
  
      return pluginObj;
  
  };
  
  AbstractPluginLoader.prototype.trySetOptions = function(plugin, filename, name, options) {
      if (options) {
          if (!plugin.setOptions) {
              error("Options have been provided but the plugin " + name + " does not support any options.");
              return null;
          }
          try {
              plugin.setOptions(options);
          }
          catch (e) {
              error("Error setting options on plugin " + name + '\n' + e.message);
              return null;
          }
      }
  };
  
  AbstractPluginLoader.prototype.validatePlugin = function(plugin, filename, name) {
      if (plugin) {
          // support plugins being a function
          // so that the plugin can be more usable programmatically
          if (typeof plugin === "function") {
              plugin = new plugin();
          }
  
          if (plugin.minVersion) {
              if (this.compareVersion(plugin.minVersion, this.less.version) < 0) {
                  error("Plugin " + name + " requires version " + this.versionToString(plugin.minVersion));
                  return null;
              }
          }
          return plugin;
      }
      return null;
  };
  
  AbstractPluginLoader.prototype.compareVersion = function(aVersion, bVersion) {
      if (typeof aVersion === "string") {
          aVersion = aVersion.match(/^(\d+)\.?(\d+)?\.?(\d+)?/);
          aVersion.shift();
      }
      for (var i = 0; i < aVersion.length; i++) {
          if (aVersion[i] !== bVersion[i]) {
              return parseInt(aVersion[i]) > parseInt(bVersion[i]) ? -1 : 1;
          }
      }
      return 0;
  };
  AbstractPluginLoader.prototype.versionToString = function(version) {
      var versionString = "";
      for (var i = 0; i < version.length; i++) {
          versionString += (versionString ? "." : "") + version[i];
      }
      return versionString;
  };
  AbstractPluginLoader.prototype.printUsage = function(plugins) {
      for (var i = 0; i < plugins.length; i++) {
          var plugin = plugins[i];
          if (plugin.printUsage) {
              plugin.printUsage();
          }
      }
  };
  
  module.exports = AbstractPluginLoader;
  
  
  },{"../functions/function-registry":26,"../less-error":36}],19:[function(require,module,exports){
  var logger = require("../logger");
  var environment = function(externalEnvironment, fileManagers) {
      this.fileManagers = fileManagers || [];
      externalEnvironment = externalEnvironment || {};
  
      var optionalFunctions = ["encodeBase64", "mimeLookup", "charsetLookup", "getSourceMapGenerator"],
          requiredFunctions = [],
          functions = requiredFunctions.concat(optionalFunctions);
  
      for (var i = 0; i < functions.length; i++) {
          var propName = functions[i],
              environmentFunc = externalEnvironment[propName];
          if (environmentFunc) {
              this[propName] = environmentFunc.bind(externalEnvironment);
          } else if (i < requiredFunctions.length) {
              this.warn("missing required function in environment - " + propName);
          }
      }
  };
  
  environment.prototype.getFileManager = function (filename, currentDirectory, options, environment, isSync) {
  
      if (!filename) {
          logger.warn("getFileManager called with no filename.. Please report this issue. continuing.");
      }
      if (currentDirectory == null) {
          logger.warn("getFileManager called with null directory.. Please report this issue. continuing.");
      }
  
      var fileManagers = this.fileManagers;
      if (options.pluginManager) {
          fileManagers = [].concat(fileManagers).concat(options.pluginManager.getFileManagers());
      }
      for (var i = fileManagers.length - 1; i >= 0 ; i--) {
          var fileManager = fileManagers[i];
          if (fileManager[isSync ? "supportsSync" : "supports"](filename, currentDirectory, options, environment)) {
              return fileManager;
          }
      }
      return null;
  };
  
  environment.prototype.addFileManager = function (fileManager) {
      this.fileManagers.push(fileManager);
  };
  
  environment.prototype.clearFileManagers = function () {
      this.fileManagers = [];
  };
  
  module.exports = environment;
  
  },{"../logger":37}],20:[function(require,module,exports){
  
  var functionRegistry = require("./function-registry"),
      Anonymous = require("../tree/anonymous"),
      Keyword = require("../tree/keyword");
  
  functionRegistry.addMultiple({
      boolean: function(condition) {
          return condition ? Keyword.True : Keyword.False;
      },
  
      'if': function(condition, trueValue, falseValue) {
          return condition ? trueValue
              : (falseValue || new Anonymous);
      }
  });
  
  },{"../tree/anonymous":48,"../tree/keyword":68,"./function-registry":26}],21:[function(require,module,exports){
  var Color = require("../tree/color"),
      functionRegistry = require("./function-registry");
  
  // Color Blending
  // ref: http://www.w3.org/TR/compositing-1
  
  function colorBlend(mode, color1, color2) {
      var ab = color1.alpha, cb, // backdrop
          as = color2.alpha, cs, // source
          ar, cr, r = [];        // result
  
      ar = as + ab * (1 - as);
      for (var i = 0; i < 3; i++) {
          cb = color1.rgb[i] / 255;
          cs = color2.rgb[i] / 255;
          cr = mode(cb, cs);
          if (ar) {
              cr = (as * cs + ab * (cb -
                    as * (cb + cs - cr))) / ar;
          }
          r[i] = cr * 255;
      }
  
      return new Color(r, ar);
  }
  
  var colorBlendModeFunctions = {
      multiply: function(cb, cs) {
          return cb * cs;
      },
      screen: function(cb, cs) {
          return cb + cs - cb * cs;
      },
      overlay: function(cb, cs) {
          cb *= 2;
          return (cb <= 1) ?
              colorBlendModeFunctions.multiply(cb, cs) :
              colorBlendModeFunctions.screen(cb - 1, cs);
      },
      softlight: function(cb, cs) {
          var d = 1, e = cb;
          if (cs > 0.5) {
              e = 1;
              d = (cb > 0.25) ? Math.sqrt(cb)
                  : ((16 * cb - 12) * cb + 4) * cb;
          }
          return cb - (1 - 2 * cs) * e * (d - cb);
      },
      hardlight: function(cb, cs) {
          return colorBlendModeFunctions.overlay(cs, cb);
      },
      difference: function(cb, cs) {
          return Math.abs(cb - cs);
      },
      exclusion: function(cb, cs) {
          return cb + cs - 2 * cb * cs;
      },
  
      // non-w3c functions:
      average: function(cb, cs) {
          return (cb + cs) / 2;
      },
      negation: function(cb, cs) {
          return 1 - Math.abs(cb + cs - 1);
      }
  };
  
  for (var f in colorBlendModeFunctions) {
      if (colorBlendModeFunctions.hasOwnProperty(f)) {
          colorBlend[f] = colorBlend.bind(null, colorBlendModeFunctions[f]);
      }
  }
  
  functionRegistry.addMultiple(colorBlend);
  
  },{"../tree/color":53,"./function-registry":26}],22:[function(require,module,exports){
  var Dimension = require("../tree/dimension"),
      Color = require("../tree/color"),
      Quoted = require("../tree/quoted"),
      Anonymous = require("../tree/anonymous"),
      functionRegistry = require("./function-registry"),
      colorFunctions;
  
  function clamp(val) {
      return Math.min(1, Math.max(0, val));
  }
  function hsla(color) {
      return colorFunctions.hsla(color.h, color.s, color.l, color.a);
  }
  function number(n) {
      if (n instanceof Dimension) {
          return parseFloat(n.unit.is('%') ? n.value / 100 : n.value);
      } else if (typeof n === 'number') {
          return n;
      } else {
          throw {
              type: "Argument",
              message: "color functions take numbers as parameters"
          };
      }
  }
  function scaled(n, size) {
      if (n instanceof Dimension && n.unit.is('%')) {
          return parseFloat(n.value * size / 100);
      } else {
          return number(n);
      }
  }
  colorFunctions = {
      rgb: function (r, g, b) {
          return colorFunctions.rgba(r, g, b, 1.0);
      },
      rgba: function (r, g, b, a) {
          var rgb = [r, g, b].map(function (c) { return scaled(c, 255); });
          a = number(a);
          return new Color(rgb, a);
      },
      hsl: function (h, s, l) {
          return colorFunctions.hsla(h, s, l, 1.0);
      },
      hsla: function (h, s, l, a) {
  
          var m1, m2;
  
          function hue(h) {
              h = h < 0 ? h + 1 : (h > 1 ? h - 1 : h);
              if (h * 6 < 1) {
                  return m1 + (m2 - m1) * h * 6;
              }
              else if (h * 2 < 1) {
                  return m2;
              }
              else if (h * 3 < 2) {
                  return m1 + (m2 - m1) * (2 / 3 - h) * 6;
              }
              else {
                  return m1;
              }
          }
  
          h = (number(h) % 360) / 360;
          s = clamp(number(s)); l = clamp(number(l)); a = clamp(number(a));
  
          m2 = l <= 0.5 ? l * (s + 1) : l + s - l * s;
          m1 = l * 2 - m2;
  
          return colorFunctions.rgba(hue(h + 1 / 3) * 255,
              hue(h)       * 255,
              hue(h - 1 / 3) * 255,
              a);
      },
  
      hsv: function(h, s, v) {
          return colorFunctions.hsva(h, s, v, 1.0);
      },
  
      hsva: function(h, s, v, a) {
          h = ((number(h) % 360) / 360) * 360;
          s = number(s); v = number(v); a = number(a);
  
          var i, f;
          i = Math.floor((h / 60) % 6);
          f = (h / 60) - i;
  
          var vs = [v,
              v * (1 - s),
              v * (1 - f * s),
              v * (1 - (1 - f) * s)];
          var perm = [[0, 3, 1],
              [2, 0, 1],
              [1, 0, 3],
              [1, 2, 0],
              [3, 1, 0],
              [0, 1, 2]];
  
          return colorFunctions.rgba(vs[perm[i][0]] * 255,
              vs[perm[i][1]] * 255,
              vs[perm[i][2]] * 255,
              a);
      },
  
      hue: function (color) {
          return new Dimension(color.toHSL().h);
      },
      saturation: function (color) {
          return new Dimension(color.toHSL().s * 100, '%');
      },
      lightness: function (color) {
          return new Dimension(color.toHSL().l * 100, '%');
      },
      hsvhue: function(color) {
          return new Dimension(color.toHSV().h);
      },
      hsvsaturation: function (color) {
          return new Dimension(color.toHSV().s * 100, '%');
      },
      hsvvalue: function (color) {
          return new Dimension(color.toHSV().v * 100, '%');
      },
      red: function (color) {
          return new Dimension(color.rgb[0]);
      },
      green: function (color) {
          return new Dimension(color.rgb[1]);
      },
      blue: function (color) {
          return new Dimension(color.rgb[2]);
      },
      alpha: function (color) {
          return new Dimension(color.toHSL().a);
      },
      luma: function (color) {
          return new Dimension(color.luma() * color.alpha * 100, '%');
      },
      luminance: function (color) {
          var luminance =
              (0.2126 * color.rgb[0] / 255) +
                  (0.7152 * color.rgb[1] / 255) +
                  (0.0722 * color.rgb[2] / 255);
  
          return new Dimension(luminance * color.alpha * 100, '%');
      },
      saturate: function (color, amount, method) {
          // filter: saturate(3.2);
          // should be kept as is, so check for color
          if (!color.rgb) {
              return null;
          }
          var hsl = color.toHSL();
  
          if (typeof method !== "undefined" && method.value === "relative") {
              hsl.s +=  hsl.s * amount.value / 100;
          }
          else {
              hsl.s += amount.value / 100;
          }
          hsl.s = clamp(hsl.s);
          return hsla(hsl);
      },
      desaturate: function (color, amount, method) {
          var hsl = color.toHSL();
  
          if (typeof method !== "undefined" && method.value === "relative") {
              hsl.s -=  hsl.s * amount.value / 100;
          }
          else {
              hsl.s -= amount.value / 100;
          }
          hsl.s = clamp(hsl.s);
          return hsla(hsl);
      },
      lighten: function (color, amount, method) {
          var hsl = color.toHSL();
  
          if (typeof method !== "undefined" && method.value === "relative") {
              hsl.l +=  hsl.l * amount.value / 100;
          }
          else {
              hsl.l += amount.value / 100;
          }
          hsl.l = clamp(hsl.l);
          return hsla(hsl);
      },
      darken: function (color, amount, method) {
          var hsl = color.toHSL();
  
          if (typeof method !== "undefined" && method.value === "relative") {
              hsl.l -=  hsl.l * amount.value / 100;
          }
          else {
              hsl.l -= amount.value / 100;
          }
          hsl.l = clamp(hsl.l);
          return hsla(hsl);
      },
      fadein: function (color, amount, method) {
          var hsl = color.toHSL();
  
          if (typeof method !== "undefined" && method.value === "relative") {
              hsl.a +=  hsl.a * amount.value / 100;
          }
          else {
              hsl.a += amount.value / 100;
          }
          hsl.a = clamp(hsl.a);
          return hsla(hsl);
      },
      fadeout: function (color, amount, method) {
          var hsl = color.toHSL();
  
          if (typeof method !== "undefined" && method.value === "relative") {
              hsl.a -=  hsl.a * amount.value / 100;
          }
          else {
              hsl.a -= amount.value / 100;
          }
          hsl.a = clamp(hsl.a);
          return hsla(hsl);
      },
      fade: function (color, amount) {
          var hsl = color.toHSL();
  
          hsl.a = amount.value / 100;
          hsl.a = clamp(hsl.a);
          return hsla(hsl);
      },
      spin: function (color, amount) {
          var hsl = color.toHSL();
          var hue = (hsl.h + amount.value) % 360;
  
          hsl.h = hue < 0 ? 360 + hue : hue;
  
          return hsla(hsl);
      },
      //
      // Copyright (c) 2006-2009 Hampton Catlin, Natalie Weizenbaum, and Chris Eppstein
      // http://sass-lang.com
      //
      mix: function (color1, color2, weight) {
          if (!color1.toHSL || !color2.toHSL) {
              console.log(color2.type);
              console.dir(color2);
          }
          if (!weight) {
              weight = new Dimension(50);
          }
          var p = weight.value / 100.0;
          var w = p * 2 - 1;
          var a = color1.toHSL().a - color2.toHSL().a;
  
          var w1 = (((w * a == -1) ? w : (w + a) / (1 + w * a)) + 1) / 2.0;
          var w2 = 1 - w1;
  
          var rgb = [color1.rgb[0] * w1 + color2.rgb[0] * w2,
              color1.rgb[1] * w1 + color2.rgb[1] * w2,
              color1.rgb[2] * w1 + color2.rgb[2] * w2];
  
          var alpha = color1.alpha * p + color2.alpha * (1 - p);
  
          return new Color(rgb, alpha);
      },
      greyscale: function (color) {
          return colorFunctions.desaturate(color, new Dimension(100));
      },
      contrast: function (color, dark, light, threshold) {
          // filter: contrast(3.2);
          // should be kept as is, so check for color
          if (!color.rgb) {
              return null;
          }
          if (typeof light === 'undefined') {
              light = colorFunctions.rgba(255, 255, 255, 1.0);
          }
          if (typeof dark === 'undefined') {
              dark = colorFunctions.rgba(0, 0, 0, 1.0);
          }
          // Figure out which is actually light and dark:
          if (dark.luma() > light.luma()) {
              var t = light;
              light = dark;
              dark = t;
          }
          if (typeof threshold === 'undefined') {
              threshold = 0.43;
          } else {
              threshold = number(threshold);
          }
          if (color.luma() < threshold) {
              return light;
          } else {
              return dark;
          }
      },
      // Changes made in 2.7.0 - Reverted in 3.0.0
      // contrast: function (color, color1, color2, threshold) {
      //     // Return which of `color1` and `color2` has the greatest contrast with `color`
      //     // according to the standard WCAG contrast ratio calculation.
      //     // http://www.w3.org/TR/WCAG20/#contrast-ratiodef
      //     // The threshold param is no longer used, in line with SASS.
      //     // filter: contrast(3.2);
      //     // should be kept as is, so check for color
      //     if (!color.rgb) {
      //         return null;
      //     }
      //     if (typeof color1 === 'undefined') {
      //         color1 = colorFunctions.rgba(0, 0, 0, 1.0);
      //     }
      //     if (typeof color2 === 'undefined') {
      //         color2 = colorFunctions.rgba(255, 255, 255, 1.0);
      //     }
      //     var contrast1, contrast2;
      //     var luma = color.luma();
      //     var luma1 = color1.luma();
      //     var luma2 = color2.luma();
      //     // Calculate contrast ratios for each color
      //     if (luma > luma1) {
      //         contrast1 = (luma + 0.05) / (luma1 + 0.05);
      //     } else {
      //         contrast1 = (luma1 + 0.05) / (luma + 0.05);
      //     }
      //     if (luma > luma2) {
      //         contrast2 = (luma + 0.05) / (luma2 + 0.05);
      //     } else {
      //         contrast2 = (luma2 + 0.05) / (luma + 0.05);
      //     }
      //     if (contrast1 > contrast2) {
      //         return color1;
      //     } else {
      //         return color2;
      //     }
      // },
      argb: function (color) {
          return new Anonymous(color.toARGB());
      },
      color: function(c) {
          if ((c instanceof Quoted) &&
              (/^#([a-f0-9]{6}|[a-f0-9]{3})$/i.test(c.value))) {
              return new Color(c.value.slice(1));
          }
          if ((c instanceof Color) || (c = Color.fromKeyword(c.value))) {
              c.value = undefined;
              return c;
          }
          throw {
              type:    "Argument",
              message: "argument must be a color keyword or 3/6 digit hex e.g. #FFF"
          };
      },
      tint: function(color, amount) {
          return colorFunctions.mix(colorFunctions.rgb(255, 255, 255), color, amount);
      },
      shade: function(color, amount) {
          return colorFunctions.mix(colorFunctions.rgb(0, 0, 0), color, amount);
      }
  };
  functionRegistry.addMultiple(colorFunctions);
  
  },{"../tree/anonymous":48,"../tree/color":53,"../tree/dimension":60,"../tree/quoted":77,"./function-registry":26}],23:[function(require,module,exports){
  module.exports = function(environment) {
      var Quoted = require("../tree/quoted"),
          URL = require("../tree/url"),
          utils = require('../utils'),
          functionRegistry = require("./function-registry"),
          fallback = function(functionThis, node) {
              return new URL(node, functionThis.index, functionThis.currentFileInfo).eval(functionThis.context);
          },
          logger = require('../logger');
  
      functionRegistry.add("data-uri", function(mimetypeNode, filePathNode) {
  
          if (!filePathNode) {
              filePathNode = mimetypeNode;
              mimetypeNode = null;
          }
  
          var mimetype = mimetypeNode && mimetypeNode.value;
          var filePath = filePathNode.value;
          var currentFileInfo = this.currentFileInfo;
          var currentDirectory = currentFileInfo.relativeUrls ?
              currentFileInfo.currentDirectory : currentFileInfo.entryPath;
  
          var fragmentStart = filePath.indexOf('#');
          var fragment = '';
          if (fragmentStart !== -1) {
              fragment = filePath.slice(fragmentStart);
              filePath = filePath.slice(0, fragmentStart);
          }
          var context = utils.clone(this.context);
          context.rawBuffer = true;
  
          var fileManager = environment.getFileManager(filePath, currentDirectory, context, environment, true);
  
          if (!fileManager) {
              return fallback(this, filePathNode);
          }
  
          var useBase64 = false;
  
          // detect the mimetype if not given
          if (!mimetypeNode) {
  
              mimetype = environment.mimeLookup(filePath);
  
              if (mimetype === "image/svg+xml") {
                  useBase64 = false;
              } else {
                  // use base 64 unless it's an ASCII or UTF-8 format
                  var charset = environment.charsetLookup(mimetype);
                  useBase64 = ['US-ASCII', 'UTF-8'].indexOf(charset) < 0;
              }
              if (useBase64) { mimetype += ';base64'; }
          }
          else {
              useBase64 = /;base64$/.test(mimetype);
          }
  
          var fileSync = fileManager.loadFileSync(filePath, currentDirectory, context, environment);
          if (!fileSync.contents) {
              logger.warn("Skipped data-uri embedding of " + filePath + " because file not found");
              return fallback(this, filePathNode || mimetypeNode);
          }
          var buf = fileSync.contents;
          if (useBase64 && !environment.encodeBase64) {
              return fallback(this, filePathNode);
          }
  
          buf = useBase64 ? environment.encodeBase64(buf) : encodeURIComponent(buf);
  
          var uri = "data:" + mimetype + ',' + buf + fragment;
  
          // IE8 cannot handle a data-uri larger than 32,768 characters. If this is exceeded
          // and the --ieCompat flag is enabled, return a normal url() instead.
          var DATA_URI_MAX = 32768;
          if (uri.length >= DATA_URI_MAX) {
  
              if (this.context.ieCompat !== false) {
                  logger.warn("Skipped data-uri embedding of " + filePath + " because its size (" + uri.length +
                      " characters) exceeds IE8-safe " + DATA_URI_MAX + " characters!");
  
                  return fallback(this, filePathNode || mimetypeNode);
              }
          }
  
          return new URL(new Quoted('"' + uri + '"', uri, false, this.index, this.currentFileInfo), this.index, this.currentFileInfo);
      });
  };
  
  },{"../logger":37,"../tree/quoted":77,"../tree/url":82,"../utils":86,"./function-registry":26}],24:[function(require,module,exports){
  var Keyword = require("../tree/keyword"),
      functionRegistry = require("./function-registry");
  
  var defaultFunc = {
      eval: function () {
          var v = this.value_, e = this.error_;
          if (e) {
              throw e;
          }
          if (v != null) {
              return v ? Keyword.True : Keyword.False;
          }
      },
      value: function (v) {
          this.value_ = v;
      },
      error: function (e) {
          this.error_ = e;
      },
      reset: function () {
          this.value_ = this.error_ = null;
      }
  };
  
  functionRegistry.add("default", defaultFunc.eval.bind(defaultFunc));
  
  module.exports = defaultFunc;
  
  },{"../tree/keyword":68,"./function-registry":26}],25:[function(require,module,exports){
  var Expression = require("../tree/expression");
  
  var functionCaller = function(name, context, index, currentFileInfo) {
      this.name = name.toLowerCase();
      this.index = index;
      this.context = context;
      this.currentFileInfo = currentFileInfo;
  
      this.func = context.frames[0].functionRegistry.get(this.name);
  };
  functionCaller.prototype.isValid = function() {
      return Boolean(this.func);
  };
  
  functionCaller.prototype.call = function(args) {
      // This code is terrible and should be replaced as per this issue...
      // https://github.com/less/less.js/issues/2477
      if (Array.isArray(args)) {
          args = args.filter(function (item) {
              if (item.type === "Comment") {
                  return false;
              }
              return true;
          })
          .map(function(item) {
              if (item.type === "Expression") {
                  var subNodes = item.value.filter(function (item) {
                      if (item.type === "Comment") {
                          return false;
                      }
                      return true;
                  });
                  if (subNodes.length === 1) {
                      return subNodes[0];
                  } else {
                      return new Expression(subNodes);
                  }
              }
              return item;
          });
      }
  
      return this.func.apply(this, args);
  };
  
  module.exports = functionCaller;
  
  },{"../tree/expression":62}],26:[function(require,module,exports){
  function makeRegistry( base ) {
      return {
          _data: {},
          add: function(name, func) {
              // precautionary case conversion, as later querying of
              // the registry by function-caller uses lower case as well.
              name = name.toLowerCase();
  
              if (this._data.hasOwnProperty(name)) {
                  // TODO warn
              }
              this._data[name] = func;
          },
          addMultiple: function(functions) {
              Object.keys(functions).forEach(
                  function(name) {
                      this.add(name, functions[name]);
                  }.bind(this));
          },
          get: function(name) {
              return this._data[name] || ( base && base.get( name ));
          },
          getLocalFunctions: function() {
              return this._data;
          },
          inherit: function() {
              return makeRegistry( this );
          },
          create: function(base) {
              return makeRegistry(base);
          }
      };
  }
  
  module.exports = makeRegistry( null );
  },{}],27:[function(require,module,exports){
  module.exports = function(environment) {
      var functions = {
          functionRegistry: require("./function-registry"),
          functionCaller: require("./function-caller")
      };
  
      // register functions
      require("./boolean");
      require("./default");
      require("./color");
      require("./color-blending");
      require("./data-uri")(environment);
      require("./math");
      require("./number");
      require("./string");
      require("./svg")(environment);
      require("./types");
  
      return functions;
  };
  
  },{"./boolean":20,"./color":22,"./color-blending":21,"./data-uri":23,"./default":24,"./function-caller":25,"./function-registry":26,"./math":29,"./number":30,"./string":31,"./svg":32,"./types":33}],28:[function(require,module,exports){
  var Dimension = require("../tree/dimension");
  
  var MathHelper = function() {
  };
  MathHelper._math = function (fn, unit, n) {
      if (!(n instanceof Dimension)) {
          throw { type: "Argument", message: "argument must be a number" };
      }
      if (unit == null) {
          unit = n.unit;
      } else {
          n = n.unify();
      }
      return new Dimension(fn(parseFloat(n.value)), unit);
  };
  module.exports = MathHelper;
  },{"../tree/dimension":60}],29:[function(require,module,exports){
  var functionRegistry = require("./function-registry"),
      mathHelper = require("./math-helper.js");
  
  var mathFunctions = {
      // name,  unit
      ceil:  null,
      floor: null,
      sqrt:  null,
      abs:   null,
      tan:   "",
      sin:   "",
      cos:   "",
      atan:  "rad",
      asin:  "rad",
      acos:  "rad"
  };
  
  for (var f in mathFunctions) {
      if (mathFunctions.hasOwnProperty(f)) {
          mathFunctions[f] = mathHelper._math.bind(null, Math[f], mathFunctions[f]);
      }
  }
  
  mathFunctions.round = function (n, f) {
      var fraction = typeof f === "undefined" ? 0 : f.value;
      return mathHelper._math(function(num) { return num.toFixed(fraction); }, null, n);
  };
  
  functionRegistry.addMultiple(mathFunctions);
  
  },{"./function-registry":26,"./math-helper.js":28}],30:[function(require,module,exports){
  var Dimension = require("../tree/dimension"),
      Anonymous = require("../tree/anonymous"),
      functionRegistry = require("./function-registry"),
      mathHelper = require("./math-helper.js");
  
  var minMax = function (isMin, args) {
      args = Array.prototype.slice.call(args);
      switch (args.length) {
          case 0: throw { type: "Argument", message: "one or more arguments required" };
      }
      var i, j, current, currentUnified, referenceUnified, unit, unitStatic, unitClone,
          order  = [], // elems only contains original argument values.
          values = {}; // key is the unit.toString() for unified Dimension values,
      // value is the index into the order array.
      for (i = 0; i < args.length; i++) {
          current = args[i];
          if (!(current instanceof Dimension)) {
              if (Array.isArray(args[i].value)) {
                  Array.prototype.push.apply(args, Array.prototype.slice.call(args[i].value));
              }
              continue;
          }
          currentUnified = current.unit.toString() === "" && unitClone !== undefined ? new Dimension(current.value, unitClone).unify() : current.unify();
          unit = currentUnified.unit.toString() === "" && unitStatic !== undefined ? unitStatic : currentUnified.unit.toString();
          unitStatic = unit !== "" && unitStatic === undefined || unit !== "" && order[0].unify().unit.toString() === "" ? unit : unitStatic;
          unitClone = unit !== "" && unitClone === undefined ? current.unit.toString() : unitClone;
          j = values[""] !== undefined && unit !== "" && unit === unitStatic ? values[""] : values[unit];
          if (j === undefined) {
              if (unitStatic !== undefined && unit !== unitStatic) {
                  throw { type: "Argument", message: "incompatible types" };
              }
              values[unit] = order.length;
              order.push(current);
              continue;
          }
          referenceUnified = order[j].unit.toString() === "" && unitClone !== undefined ? new Dimension(order[j].value, unitClone).unify() : order[j].unify();
          if ( isMin && currentUnified.value < referenceUnified.value ||
              !isMin && currentUnified.value > referenceUnified.value) {
              order[j] = current;
          }
      }
      if (order.length == 1) {
          return order[0];
      }
      args = order.map(function (a) { return a.toCSS(this.context); }).join(this.context.compress ? "," : ", ");
      return new Anonymous((isMin ? "min" : "max") + "(" + args + ")");
  };
  functionRegistry.addMultiple({
      min: function () {
          return minMax(true, arguments);
      },
      max: function () {
          return minMax(false, arguments);
      },
      convert: function (val, unit) {
          return val.convertTo(unit.value);
      },
      pi: function () {
          return new Dimension(Math.PI);
      },
      mod: function(a, b) {
          return new Dimension(a.value % b.value, a.unit);
      },
      pow: function(x, y) {
          if (typeof x === "number" && typeof y === "number") {
              x = new Dimension(x);
              y = new Dimension(y);
          } else if (!(x instanceof Dimension) || !(y instanceof Dimension)) {
              throw { type: "Argument", message: "arguments must be numbers" };
          }
  
          return new Dimension(Math.pow(x.value, y.value), x.unit);
      },
      percentage: function (n) {
          var result = mathHelper._math(function(num) {
              return num * 100;
          }, '%', n);
  
          return result;
      }
  });
  
  },{"../tree/anonymous":48,"../tree/dimension":60,"./function-registry":26,"./math-helper.js":28}],31:[function(require,module,exports){
  var Quoted = require("../tree/quoted"),
      Anonymous = require("../tree/anonymous"),
      JavaScript = require("../tree/javascript"),
      functionRegistry = require("./function-registry");
  
  functionRegistry.addMultiple({
      e: function (str) {
          return new Anonymous(str instanceof JavaScript ? str.evaluated : str.value);
      },
      escape: function (str) {
          return new Anonymous(
              encodeURI(str.value).replace(/=/g, "%3D").replace(/:/g, "%3A").replace(/#/g, "%23").replace(/;/g, "%3B")
                  .replace(/\(/g, "%28").replace(/\)/g, "%29"));
      },
      replace: function (string, pattern, replacement, flags) {
          var result = string.value;
          replacement = (replacement.type === "Quoted") ?
              replacement.value : replacement.toCSS();
          result = result.replace(new RegExp(pattern.value, flags ? flags.value : ''), replacement);
          return new Quoted(string.quote || '', result, string.escaped);
      },
      '%': function (string /* arg, arg, ... */) {
          var args = Array.prototype.slice.call(arguments, 1),
              result = string.value;
  
          for (var i = 0; i < args.length; i++) {
              /* jshint loopfunc:true */
              result = result.replace(/%[sda]/i, function(token) {
                  var value = ((args[i].type === "Quoted") &&
                      token.match(/s/i)) ? args[i].value : args[i].toCSS();
                  return token.match(/[A-Z]$/) ? encodeURIComponent(value) : value;
              });
          }
          result = result.replace(/%%/g, '%');
          return new Quoted(string.quote || '', result, string.escaped);
      }
  });
  
  },{"../tree/anonymous":48,"../tree/javascript":66,"../tree/quoted":77,"./function-registry":26}],32:[function(require,module,exports){
  module.exports = function(environment) {
      var Dimension = require("../tree/dimension"),
          Color = require("../tree/color"),
          Expression = require("../tree/expression"),
          Quoted = require("../tree/quoted"),
          URL = require("../tree/url"),
          functionRegistry = require("./function-registry");
  
      functionRegistry.add("svg-gradient", function(direction) {
  
          var stops,
              gradientDirectionSvg,
              gradientType = "linear",
              rectangleDimension = 'x="0" y="0" width="1" height="1"',
              renderEnv = {compress: false},
              returner,
              directionValue = direction.toCSS(renderEnv),
              i, color, position, positionValue, alpha;
  
          function throwArgumentDescriptor() {
              throw { type: "Argument",
                  message: "svg-gradient expects direction, start_color [start_position], [color position,]...," +
                              " end_color [end_position] or direction, color list" };
          }
  
          if (arguments.length == 2) {
              if (arguments[1].value.length < 2) {
                  throwArgumentDescriptor();
              }
              stops = arguments[1].value;
          } else if (arguments.length < 3) {
              throwArgumentDescriptor();
          } else {
              stops = Array.prototype.slice.call(arguments, 1);
          }
  
          switch (directionValue) {
              case "to bottom":
                  gradientDirectionSvg = 'x1="0%" y1="0%" x2="0%" y2="100%"';
                  break;
              case "to right":
                  gradientDirectionSvg = 'x1="0%" y1="0%" x2="100%" y2="0%"';
                  break;
              case "to bottom right":
                  gradientDirectionSvg = 'x1="0%" y1="0%" x2="100%" y2="100%"';
                  break;
              case "to top right":
                  gradientDirectionSvg = 'x1="0%" y1="100%" x2="100%" y2="0%"';
                  break;
              case "ellipse":
              case "ellipse at center":
                  gradientType = "radial";
                  gradientDirectionSvg = 'cx="50%" cy="50%" r="75%"';
                  rectangleDimension = 'x="-50" y="-50" width="101" height="101"';
                  break;
              default:
                  throw { type: "Argument", message: "svg-gradient direction must be 'to bottom', 'to right'," +
                      " 'to bottom right', 'to top right' or 'ellipse at center'" };
          }
          returner = '<?xml version="1.0" ?>' +
              '<svg xmlns="http://www.w3.org/2000/svg" version="1.1" width="100%" height="100%" viewBox="0 0 1 1" preserveAspectRatio="none">' +
              '<' + gradientType + 'Gradient id="gradient" gradientUnits="userSpaceOnUse" ' + gradientDirectionSvg + '>';
  
          for (i = 0; i < stops.length; i += 1) {
              if (stops[i] instanceof Expression) {
                  color = stops[i].value[0];
                  position = stops[i].value[1];
              } else {
                  color = stops[i];
                  position = undefined;
              }
  
              if (!(color instanceof Color) || (!((i === 0 || i + 1 === stops.length) && position === undefined) && !(position instanceof Dimension))) {
                  throwArgumentDescriptor();
              }
              positionValue = position ? position.toCSS(renderEnv) : i === 0 ? "0%" : "100%";
              alpha = color.alpha;
              returner += '<stop offset="' + positionValue + '" stop-color="' + color.toRGB() + '"' + (alpha < 1 ? ' stop-opacity="' + alpha + '"' : '') + '/>';
          }
          returner += '</' + gradientType + 'Gradient>' +
              '<rect ' + rectangleDimension + ' fill="url(#gradient)" /></svg>';
  
          returner = encodeURIComponent(returner);
  
          returner = "data:image/svg+xml," + returner;
          return new URL(new Quoted("'" + returner + "'", returner, false, this.index, this.currentFileInfo), this.index, this.currentFileInfo);
      });
  };
  
  },{"../tree/color":53,"../tree/dimension":60,"../tree/expression":62,"../tree/quoted":77,"../tree/url":82,"./function-registry":26}],33:[function(require,module,exports){
  var Keyword = require("../tree/keyword"),
      DetachedRuleset = require("../tree/detached-ruleset"),
      Dimension = require("../tree/dimension"),
      Color = require("../tree/color"),
      Quoted = require("../tree/quoted"),
      Anonymous = require("../tree/anonymous"),
      URL = require("../tree/url"),
      Operation = require("../tree/operation"),
      functionRegistry = require("./function-registry");
  
  var isa = function (n, Type) {
          return (n instanceof Type) ? Keyword.True : Keyword.False;
      },
      isunit = function (n, unit) {
          if (unit === undefined) {
              throw { type: "Argument", message: "missing the required second argument to isunit." };
          }
          unit = typeof unit.value === "string" ? unit.value : unit;
          if (typeof unit !== "string") {
              throw { type: "Argument", message: "Second argument to isunit should be a unit or a string." };
          }
          return (n instanceof Dimension) && n.unit.is(unit) ? Keyword.True : Keyword.False;
      },
      getItemsFromNode = function(node) {
          // handle non-array values as an array of length 1
          // return 'undefined' if index is invalid
          var items = Array.isArray(node.value) ?
              node.value : Array(node);
  
          return items;
      };
  functionRegistry.addMultiple({
      isruleset: function (n) {
          return isa(n, DetachedRuleset);
      },
      iscolor: function (n) {
          return isa(n, Color);
      },
      isnumber: function (n) {
          return isa(n, Dimension);
      },
      isstring: function (n) {
          return isa(n, Quoted);
      },
      iskeyword: function (n) {
          return isa(n, Keyword);
      },
      isurl: function (n) {
          return isa(n, URL);
      },
      ispixel: function (n) {
          return isunit(n, 'px');
      },
      ispercentage: function (n) {
          return isunit(n, '%');
      },
      isem: function (n) {
          return isunit(n, 'em');
      },
      isunit: isunit,
      unit: function (val, unit) {
          if (!(val instanceof Dimension)) {
              throw { type: "Argument",
                  message: "the first argument to unit must be a number" +
                      (val instanceof Operation ? ". Have you forgotten parenthesis?" : "") };
          }
          if (unit) {
              if (unit instanceof Keyword) {
                  unit = unit.value;
              } else {
                  unit = unit.toCSS();
              }
          } else {
              unit = "";
          }
          return new Dimension(val.value, unit);
      },
      "get-unit": function (n) {
          return new Anonymous(n.unit);
      },
      extract: function(values, index) {
          index = index.value - 1; // (1-based index)
  
          return getItemsFromNode(values)[index];
      },
      length: function(values) {
          return new Dimension(getItemsFromNode(values).length);
      }
  });
  
  },{"../tree/anonymous":48,"../tree/color":53,"../tree/detached-ruleset":59,"../tree/dimension":60,"../tree/keyword":68,"../tree/operation":74,"../tree/quoted":77,"../tree/url":82,"./function-registry":26}],34:[function(require,module,exports){
  var contexts = require("./contexts"),
      Parser = require('./parser/parser'),
      LessError = require('./less-error'),
      utils = require('./utils'),
      PromiseConstructor = typeof Promise === 'undefined' ? require('promise') : Promise;
  
  module.exports = function(environment) {
  
      // FileInfo = {
      //  'relativeUrls' - option - whether to adjust URL's to be relative
      //  'filename' - full resolved filename of current file
      //  'rootpath' - path to append to normal URLs for this node
      //  'currentDirectory' - path to the current file, absolute
      //  'rootFilename' - filename of the base file
      //  'entryPath' - absolute path to the entry file
      //  'reference' - whether the file should not be output and only output parts that are referenced
  
      var ImportManager = function(less, context, rootFileInfo) {
          this.less = less;
          this.rootFilename = rootFileInfo.filename;
          this.paths = context.paths || [];  // Search paths, when importing
          this.contents = {};             // map - filename to contents of all the files
          this.contentsIgnoredChars = {}; // map - filename to lines at the beginning of each file to ignore
          this.mime = context.mime;
          this.error = null;
          this.context = context;
          // Deprecated? Unused outside of here, could be useful.
          this.queue = [];        // Files which haven't been imported yet
          this.files = {};        // Holds the imported parse trees.
      };
      
      /**
       * Add an import to be imported
       * @param path - the raw path
       * @param tryAppendExtension - whether to try appending a file extension (.less or .js if the path has no extension)
       * @param currentFileInfo - the current file info (used for instance to work out relative paths)
       * @param importOptions - import options
       * @param callback - callback for when it is imported
       */
      ImportManager.prototype.push = function (path, tryAppendExtension, currentFileInfo, importOptions, callback) {
          var importManager = this,
              pluginLoader = this.context.pluginManager.Loader;
  
          this.queue.push(path);
  
          var fileParsedFunc = function (e, root, fullPath) {
              importManager.queue.splice(importManager.queue.indexOf(path), 1); // Remove the path from the queue
  
              var importedEqualsRoot = fullPath === importManager.rootFilename;
              if (importOptions.optional && e) {
                  callback(null, {rules:[]}, false, null);
              }
              else {
                  if (!importManager.files[fullPath]) {
                      importManager.files[fullPath] = { root: root, options: importOptions };
                  } 
                  if (e && !importManager.error) { importManager.error = e; }
                  callback(e, root, importedEqualsRoot, fullPath);
              }
          };
  
          var newFileInfo = {
              relativeUrls: this.context.relativeUrls,
              entryPath: currentFileInfo.entryPath,
              rootpath: currentFileInfo.rootpath,
              rootFilename: currentFileInfo.rootFilename
          };
  
          var fileManager = environment.getFileManager(path, currentFileInfo.currentDirectory, this.context, environment);
  
          if (!fileManager) {
              fileParsedFunc({ message: "Could not find a file-manager for " + path });
              return;
          }
  
          var loadFileCallback = function(loadedFile) {
              var plugin,
                  resolvedFilename = loadedFile.filename,
                  contents = loadedFile.contents.replace(/^\uFEFF/, '');
  
              // Pass on an updated rootpath if path of imported file is relative and file
              // is in a (sub|sup) directory
              //
              // Examples:
              // - If path of imported file is 'module/nav/nav.less' and rootpath is 'less/',
              //   then rootpath should become 'less/module/nav/'
              // - If path of imported file is '../mixins.less' and rootpath is 'less/',
              //   then rootpath should become 'less/../'
              newFileInfo.currentDirectory = fileManager.getPath(resolvedFilename);
              if (newFileInfo.relativeUrls) {
                  newFileInfo.rootpath = fileManager.join(
                      (importManager.context.rootpath || ""),
                      fileManager.pathDiff(newFileInfo.currentDirectory, newFileInfo.entryPath));
  
                  if (!fileManager.isPathAbsolute(newFileInfo.rootpath) && fileManager.alwaysMakePathsAbsolute()) {
                      newFileInfo.rootpath = fileManager.join(newFileInfo.entryPath, newFileInfo.rootpath);
                  }
              }
              newFileInfo.filename = resolvedFilename;
  
              var newEnv = new contexts.Parse(importManager.context);
  
              newEnv.processImports = false;
              importManager.contents[resolvedFilename] = contents;
  
              if (currentFileInfo.reference || importOptions.reference) {
                  newFileInfo.reference = true;
              }
  
              if (importOptions.isPlugin) {
                  plugin = pluginLoader.evalPlugin(contents, newEnv, importManager, importOptions.pluginArgs, newFileInfo);
                  if (plugin instanceof LessError) {
                      fileParsedFunc(plugin, null, resolvedFilename);
                  }
                  else {
                      fileParsedFunc(null, plugin, resolvedFilename);
                  }
              } else if (importOptions.inline) {
                  fileParsedFunc(null, contents, resolvedFilename);
              } else {
                  
                  // import (multiple) parse trees apparently get altered and can't be cached.
                  // TODO: investigate why this is
                  if (importManager.files[resolvedFilename] 
                      && !importManager.files[resolvedFilename].options.multiple
                      && !importOptions.multiple) {
  
                      fileParsedFunc(null, importManager.files[resolvedFilename].root, resolvedFilename);
                  }
                  else {
                      new Parser(newEnv, importManager, newFileInfo).parse(contents, function (e, root) {
                          fileParsedFunc(e, root, resolvedFilename);
                      });
                  }
              }
          };
          var promise, context = utils.clone(this.context);
  
          if (tryAppendExtension) {
              context.ext = importOptions.isPlugin ? ".js" : ".less";
          }
  
          if (importOptions.isPlugin) {
              promise = pluginLoader.loadPlugin(path, currentFileInfo.currentDirectory, context, environment, fileManager);
          }
          else {
              promise = fileManager.loadFile(path, currentFileInfo.currentDirectory, context, environment, 
                  function(err, loadedFile) {
                      if (err) {
                          fileParsedFunc(err);
                      } else {
                          loadFileCallback(loadedFile);
                      }
                  });
          }
          if (promise) {
              promise.then(loadFileCallback, fileParsedFunc);
          }
  
      };
      return ImportManager;
  };
  
  },{"./contexts":12,"./less-error":36,"./parser/parser":42,"./utils":86,"promise":undefined}],35:[function(require,module,exports){
  module.exports = function(environment, fileManagers) {
      var SourceMapOutput, SourceMapBuilder, ParseTree, ImportManager, Environment;
  
      var initial = {
          version: [3, 0, 0],
          data: require('./data'),
          tree: require('./tree'),
          Environment: (Environment = require("./environment/environment")),
          AbstractFileManager: require("./environment/abstract-file-manager"),
          AbstractPluginLoader: require("./environment/abstract-plugin-loader"),
          environment: (environment = new Environment(environment, fileManagers)),
          visitors: require('./visitors'),
          Parser: require('./parser/parser'),
          functions: require('./functions')(environment),
          contexts: require("./contexts"),
          SourceMapOutput: (SourceMapOutput = require('./source-map-output')(environment)),
          SourceMapBuilder: (SourceMapBuilder = require('./source-map-builder')(SourceMapOutput, environment)),
          ParseTree: (ParseTree = require('./parse-tree')(SourceMapBuilder)),
          ImportManager: (ImportManager = require('./import-manager')(environment)),
          render: require("./render")(environment, ParseTree, ImportManager),
          parse: require("./parse")(environment, ParseTree, ImportManager),
          LessError: require('./less-error'),
          transformTree: require('./transform-tree'),
          utils: require('./utils'),
          PluginManager: require('./plugin-manager'),
          logger: require('./logger')
      };
  
      // Create a public API
  
      var ctor = function(t) {
          return function() {
              var obj = Object.create(t.prototype);
              t.apply(obj, Array.prototype.slice.call(arguments, 0));
              return obj;
          };
      };
      var t, api = Object.create(initial);
      for (var n in initial.tree) {
          /* eslint guard-for-in: 0 */
          t = initial.tree[n];
          if (typeof t === "function") {
              api[n.toLowerCase()] = ctor(t);
          }
          else {
              api[n] = Object.create(null);
              for (var o in t) {
                  /* eslint guard-for-in: 0 */
                  api[n][o.toLowerCase()] = ctor(t[o]);
              }
          }
      }
  
      return api;
  };
  
  },{"./contexts":12,"./data":14,"./environment/abstract-file-manager":17,"./environment/abstract-plugin-loader":18,"./environment/environment":19,"./functions":27,"./import-manager":34,"./less-error":36,"./logger":37,"./parse":39,"./parse-tree":38,"./parser/parser":42,"./plugin-manager":43,"./render":44,"./source-map-builder":45,"./source-map-output":46,"./transform-tree":47,"./tree":65,"./utils":86,"./visitors":90}],36:[function(require,module,exports){
  var utils = require('./utils');
  /**
   * This is a centralized class of any error that could be thrown internally (mostly by the parser).
   * Besides standard .message it keeps some additional data like a path to the file where the error
   * occurred along with line and column numbers.
   *
   * @class
   * @extends Error
   * @type {module.LessError}
   *
   * @prop {string} type
   * @prop {string} filename
   * @prop {number} index
   * @prop {number} line
   * @prop {number} column
   * @prop {number} callLine
   * @prop {number} callExtract
   * @prop {string[]} extract
   *
   * @param {Object} e              - An error object to wrap around or just a descriptive object
   * @param {Object} importManager  - An instance of ImportManager (see import-manager.js)
   * @param {string} [currentFilename]
   */
  var LessError = module.exports = function LessError(e, importManager, currentFilename) {
      Error.call(this);
  
      var filename = e.filename || currentFilename;
  
      this.message = e.message;
      this.stack = e.stack;
  
      if (importManager && filename) {
          var input = importManager.contents[filename],
              loc = utils.getLocation(e.index, input),
              line = loc.line,
              col  = loc.column,
              callLine = e.call && utils.getLocation(e.call, input).line,
              lines = input.split('\n');
  
          this.type = e.type || 'Syntax';
          this.filename = filename;
          this.index = e.index;
          this.line = typeof line === 'number' ? line + 1 : null;
          this.column = col;
  
          if (!this.line && this.stack) {
              var found = this.stack.match(/(<anonymous>|Function):(\d+):(\d+)/);
  
              if (found) {
                  if (found[2]) {
                      this.line = parseInt(found[2]) - 2;
                  }
                  if (found[3]) {
                      this.column = parseInt(found[3]);
                  }
              }
          }
  
          this.callLine = callLine + 1;
          this.callExtract = lines[callLine];
          
          this.extract = [
              lines[this.line - 2],
              lines[this.line - 1],
              lines[this.line]
          ];
  
      }
  
  };
  
  if (typeof Object.create === 'undefined') {
      var F = function () {};
      F.prototype = Error.prototype;
      LessError.prototype = new F();
  } else {
      LessError.prototype = Object.create(Error.prototype);
  }
  
  LessError.prototype.constructor = LessError;
  
  /**
   * An overridden version of the default Object.prototype.toString
   * which uses additional information to create a helpful message.
   *
   * @param {Object} options
   * @returns {string}
   */
  LessError.prototype.toString = function(options) {
      options = options || {};
  
      var message = '';
      var extract = this.extract || [];
      var error = [];
      var stylize = function (str) { return str; };
      if (options.stylize) {
          var type = typeof options.stylize;
          if (type !== 'function') {
              throw Error('options.stylize should be a function, got a ' + type + '!');
          }
          stylize = options.stylize;
      }
  
      if (this.line !== null) {
          if (typeof extract[0] === 'string') {
              error.push(stylize((this.line - 1) + ' ' + extract[0], 'grey'));
          }
  
          if (typeof extract[1] === 'string') {
              var errorTxt = this.line + ' ';
              if (extract[1]) {
                  errorTxt += extract[1].slice(0, this.column) +
                      stylize(stylize(stylize(extract[1].substr(this.column, 1), 'bold') +
                          extract[1].slice(this.column + 1), 'red'), 'inverse');
              }
              error.push(errorTxt);
          }
  
          if (typeof extract[2] === 'string') {
              error.push(stylize((this.line + 1) + ' ' + extract[2], 'grey'));
          }
          error = error.join('\n') + stylize('', 'reset') + '\n';
      }
  
      message += stylize(this.type + 'Error: ' + this.message, 'red');
      if (this.filename) {
          message += stylize(' in ', 'red') + this.filename;
      }
      if (this.line) {
          message += stylize(' on line ' + this.line + ', column ' + (this.column + 1) + ':', 'grey');
      }
  
      message += '\n' + error;
  
      if (this.callLine) {
          message += stylize('from ', 'red') + (this.filename || '') + '/n';
          message += stylize(this.callLine, 'grey') + ' ' + this.callExtract + '/n';
      }
  
      return message;
  };
  
  },{"./utils":86}],37:[function(require,module,exports){
  module.exports = {
      error: function(msg) {
          this._fireEvent("error", msg);
      },
      warn: function(msg) {
          this._fireEvent("warn", msg);
      },
      info: function(msg) {
          this._fireEvent("info", msg);
      },
      debug: function(msg) {
          this._fireEvent("debug", msg);
      },
      addListener: function(listener) {
          this._listeners.push(listener);
      },
      removeListener: function(listener) {
          for (var i = 0; i < this._listeners.length; i++) {
              if (this._listeners[i] === listener) {
                  this._listeners.splice(i, 1);
                  return;
              }
          }
      },
      _fireEvent: function(type, msg) {
          for (var i = 0; i < this._listeners.length; i++) {
              var logFunction = this._listeners[i][type];
              if (logFunction) {
                  logFunction(msg);
              }
          }
      },
      _listeners: []
  };
  
  },{}],38:[function(require,module,exports){
  var LessError = require('./less-error'),
      transformTree = require("./transform-tree"),
      logger = require("./logger");
  
  module.exports = function(SourceMapBuilder) {
      var ParseTree = function(root, imports) {
          this.root = root;
          this.imports = imports;
      };
  
      ParseTree.prototype.toCSS = function(options) {
          var evaldRoot, result = {}, sourceMapBuilder;
          try {
              evaldRoot = transformTree(this.root, options);
          } catch (e) {
              throw new LessError(e, this.imports);
          }
  
          try {
              var compress = Boolean(options.compress);
              if (compress) {
                  logger.warn("The compress option has been deprecated. We recommend you use a dedicated css minifier, for instance see less-plugin-clean-css.");
              }
  
              var toCSSOptions = {
                  compress: compress,
                  dumpLineNumbers: options.dumpLineNumbers,
                  strictUnits: Boolean(options.strictUnits),
                  numPrecision: 8};
  
              if (options.sourceMap) {
                  sourceMapBuilder = new SourceMapBuilder(options.sourceMap);
                  result.css = sourceMapBuilder.toCSS(evaldRoot, toCSSOptions, this.imports);
              } else {
                  result.css = evaldRoot.toCSS(toCSSOptions);
              }
          } catch (e) {
              throw new LessError(e, this.imports);
          }
  
          if (options.pluginManager) {
              var postProcessors = options.pluginManager.getPostProcessors();
              for (var i = 0; i < postProcessors.length; i++) {
                  result.css = postProcessors[i].process(result.css, { sourceMap: sourceMapBuilder, options: options, imports: this.imports });
              }
          }
          if (options.sourceMap) {
              result.map = sourceMapBuilder.getExternalSourceMap();
          }
  
          result.imports = [];
          for (var file in this.imports.files) {
              if (this.imports.files.hasOwnProperty(file) && file !== this.imports.rootFilename) {
                  result.imports.push(file);
              }
          }
          return result;
      };
      return ParseTree;
  };
  
  },{"./less-error":36,"./logger":37,"./transform-tree":47}],39:[function(require,module,exports){
  var PromiseConstructor,
      contexts = require("./contexts"),
      Parser = require('./parser/parser'),
      PluginManager = require('./plugin-manager'),
      LessError = require('./less-error'),
      utils = require('./utils');
  
  module.exports = function(environment, ParseTree, ImportManager) {
      var parse = function (input, options, callback) {
  
          if (typeof options === 'function') {
              callback = options;
              options = utils.defaults(this.options, {});
          }
          else {
              options = utils.defaults(this.options, options || {});
          }
  
          if (!callback) {
              if (!PromiseConstructor) {
                  PromiseConstructor = typeof Promise === 'undefined' ? require('promise') : Promise;
              }
              var self = this;
              return new PromiseConstructor(function (resolve, reject) {
                  parse.call(self, input, options, function(err, output) {
                      if (err) {
                          reject(err);
                      } else {
                          resolve(output);
                      }
                  });
              });
          } else {
              var context,
                  rootFileInfo,
                  pluginManager = new PluginManager(this, true);
  
              options.pluginManager = pluginManager;
  
              context = new contexts.Parse(options);
  
              if (options.rootFileInfo) {
                  rootFileInfo = options.rootFileInfo;
              } else {
                  var filename = options.filename || "input";
                  var entryPath = filename.replace(/[^\/\\]*$/, "");
                  rootFileInfo = {
                      filename: filename,
                      relativeUrls: context.relativeUrls,
                      rootpath: context.rootpath || "",
                      currentDirectory: entryPath,
                      entryPath: entryPath,
                      rootFilename: filename
                  };
                  // add in a missing trailing slash
                  if (rootFileInfo.rootpath && rootFileInfo.rootpath.slice(-1) !== "/") {
                      rootFileInfo.rootpath += "/";
                  }
              }
  
              var imports = new ImportManager(this, context, rootFileInfo);
              this.importManager = imports;
  
              // TODO: allow the plugins to be just a list of paths or names
              // Do an async plugin queue like lessc
  
              if (options.plugins) {
                  options.plugins.forEach(function(plugin) {
                      var evalResult, contents;
                      if (plugin.fileContent) {
                          contents = plugin.fileContent.replace(/^\uFEFF/, '');
                          evalResult = pluginManager.Loader.evalPlugin(contents, context, imports, plugin.options, plugin.filename);
                          if (evalResult instanceof LessError) {
                              return callback(evalResult);
                          }
                      }
                      else {
                          pluginManager.addPlugin(plugin);
                      }
                  });
              }
              
              new Parser(context, imports, rootFileInfo)
                  .parse(input, function (e, root) {
                      if (e) { return callback(e); }
                      callback(null, root, imports, options);
                  }, options);
          }
      };
      return parse;
  };
  
  },{"./contexts":12,"./less-error":36,"./parser/parser":42,"./plugin-manager":43,"./utils":86,"promise":undefined}],40:[function(require,module,exports){
  // Split the input into chunks.
  module.exports = function (input, fail) {
      var len = input.length, level = 0, parenLevel = 0,
          lastOpening, lastOpeningParen, lastMultiComment, lastMultiCommentEndBrace,
          chunks = [], emitFrom = 0,
          chunkerCurrentIndex, currentChunkStartIndex, cc, cc2, matched;
  
      function emitChunk(force) {
          var len = chunkerCurrentIndex - emitFrom;
          if (((len < 512) && !force) || !len) {
              return;
          }
          chunks.push(input.slice(emitFrom, chunkerCurrentIndex + 1));
          emitFrom = chunkerCurrentIndex + 1;
      }
  
      for (chunkerCurrentIndex = 0; chunkerCurrentIndex < len; chunkerCurrentIndex++) {
          cc = input.charCodeAt(chunkerCurrentIndex);
          if (((cc >= 97) && (cc <= 122)) || (cc < 34)) {
              // a-z or whitespace
              continue;
          }
  
          switch (cc) {
              case 40:                        // (
                  parenLevel++;
                  lastOpeningParen = chunkerCurrentIndex;
                  continue;
              case 41:                        // )
                  if (--parenLevel < 0) {
                      return fail("missing opening `(`", chunkerCurrentIndex);
                  }
                  continue;
              case 59:                        // ;
                  if (!parenLevel) { emitChunk(); }
                  continue;
              case 123:                       // {
                  level++;
                  lastOpening = chunkerCurrentIndex;
                  continue;
              case 125:                       // }
                  if (--level < 0) {
                      return fail("missing opening `{`", chunkerCurrentIndex);
                  }
                  if (!level && !parenLevel) { emitChunk(); }
                  continue;
              case 92:                        // \
                  if (chunkerCurrentIndex < len - 1) { chunkerCurrentIndex++; continue; }
                  return fail("unescaped `\\`", chunkerCurrentIndex);
              case 34:
              case 39:
              case 96:                        // ", ' and `
                  matched = 0;
                  currentChunkStartIndex = chunkerCurrentIndex;
                  for (chunkerCurrentIndex = chunkerCurrentIndex + 1; chunkerCurrentIndex < len; chunkerCurrentIndex++) {
                      cc2 = input.charCodeAt(chunkerCurrentIndex);
                      if (cc2 > 96) { continue; }
                      if (cc2 == cc) { matched = 1; break; }
                      if (cc2 == 92) {        // \
                          if (chunkerCurrentIndex == len - 1) {
                              return fail("unescaped `\\`", chunkerCurrentIndex);
                          }
                          chunkerCurrentIndex++;
                      }
                  }
                  if (matched) { continue; }
                  return fail("unmatched `" + String.fromCharCode(cc) + "`", currentChunkStartIndex);
              case 47:                        // /, check for comment
                  if (parenLevel || (chunkerCurrentIndex == len - 1)) { continue; }
                  cc2 = input.charCodeAt(chunkerCurrentIndex + 1);
                  if (cc2 == 47) {
                      // //, find lnfeed
                      for (chunkerCurrentIndex = chunkerCurrentIndex + 2; chunkerCurrentIndex < len; chunkerCurrentIndex++) {
                          cc2 = input.charCodeAt(chunkerCurrentIndex);
                          if ((cc2 <= 13) && ((cc2 == 10) || (cc2 == 13))) { break; }
                      }
                  } else if (cc2 == 42) {
                      // /*, find */
                      lastMultiComment = currentChunkStartIndex = chunkerCurrentIndex;
                      for (chunkerCurrentIndex = chunkerCurrentIndex + 2; chunkerCurrentIndex < len - 1; chunkerCurrentIndex++) {
                          cc2 = input.charCodeAt(chunkerCurrentIndex);
                          if (cc2 == 125) { lastMultiCommentEndBrace = chunkerCurrentIndex; }
                          if (cc2 != 42) { continue; }
                          if (input.charCodeAt(chunkerCurrentIndex + 1) == 47) { break; }
                      }
                      if (chunkerCurrentIndex == len - 1) {
                          return fail("missing closing `*/`", currentChunkStartIndex);
                      }
                      chunkerCurrentIndex++;
                  }
                  continue;
              case 42:                       // *, check for unmatched */
                  if ((chunkerCurrentIndex < len - 1) && (input.charCodeAt(chunkerCurrentIndex + 1) == 47)) {
                      return fail("unmatched `/*`", chunkerCurrentIndex);
                  }
                  continue;
          }
      }
  
      if (level !== 0) {
          if ((lastMultiComment > lastOpening) && (lastMultiCommentEndBrace > lastMultiComment)) {
              return fail("missing closing `}` or `*/`", lastOpening);
          } else {
              return fail("missing closing `}`", lastOpening);
          }
      } else if (parenLevel !== 0) {
          return fail("missing closing `)`", lastOpeningParen);
      }
  
      emitChunk(true);
      return chunks;
  };
  
  },{}],41:[function(require,module,exports){
  var chunker = require('./chunker');
  
  module.exports = function() {
      var input,       // Less input string
          j,           // current chunk
          saveStack = [],   // holds state for backtracking
          furthest,    // furthest index the parser has gone to
          furthestPossibleErrorMessage, // if this is furthest we got to, this is the probably cause
          chunks,      // chunkified input
          current,     // current chunk
          currentPos,  // index of current chunk, in `input`
          parserInput = {};
  
      var CHARCODE_SPACE = 32,
          CHARCODE_TAB = 9,
          CHARCODE_LF = 10,
          CHARCODE_CR = 13,
          CHARCODE_PLUS = 43,
          CHARCODE_COMMA = 44,
          CHARCODE_FORWARD_SLASH = 47,
          CHARCODE_9 = 57;
  
      function skipWhitespace(length) {
          var oldi = parserInput.i, oldj = j,
              curr = parserInput.i - currentPos,
              endIndex = parserInput.i + current.length - curr,
              mem = (parserInput.i += length),
              inp = input,
              c, nextChar, comment;
  
          for (; parserInput.i < endIndex; parserInput.i++) {
              c = inp.charCodeAt(parserInput.i);
  
              if (parserInput.autoCommentAbsorb && c === CHARCODE_FORWARD_SLASH) {
                  nextChar = inp.charAt(parserInput.i + 1);
                  if (nextChar === '/') {
                      comment = {index: parserInput.i, isLineComment: true};
                      var nextNewLine = inp.indexOf("\n", parserInput.i + 2);
                      if (nextNewLine < 0) {
                          nextNewLine = endIndex;
                      }
                      parserInput.i = nextNewLine;
                      comment.text = inp.substr(comment.index, parserInput.i - comment.index);
                      parserInput.commentStore.push(comment);
                      continue;
                  } else if (nextChar === '*') {
                      var nextStarSlash = inp.indexOf("*/", parserInput.i + 2);
                      if (nextStarSlash >= 0) {
                          comment = {
                              index: parserInput.i,
                              text: inp.substr(parserInput.i, nextStarSlash + 2 - parserInput.i),
                              isLineComment: false
                          };
                          parserInput.i += comment.text.length - 1;
                          parserInput.commentStore.push(comment);
                          continue;
                      }
                  }
                  break;
              }
  
              if ((c !== CHARCODE_SPACE) && (c !== CHARCODE_LF) && (c !== CHARCODE_TAB) && (c !== CHARCODE_CR)) {
                  break;
              }
          }
  
          current = current.slice(length + parserInput.i - mem + curr);
          currentPos = parserInput.i;
  
          if (!current.length) {
              if (j < chunks.length - 1) {
                  current = chunks[++j];
                  skipWhitespace(0); // skip space at the beginning of a chunk
                  return true; // things changed
              }
              parserInput.finished = true;
          }
  
          return oldi !== parserInput.i || oldj !== j;
      }
  
      parserInput.save = function() {
          currentPos = parserInput.i;
          saveStack.push( { current: current, i: parserInput.i, j: j });
      };
      parserInput.restore = function(possibleErrorMessage) {
  
          if (parserInput.i > furthest || (parserInput.i === furthest && possibleErrorMessage && !furthestPossibleErrorMessage)) {
              furthest = parserInput.i;
              furthestPossibleErrorMessage = possibleErrorMessage;
          }
          var state = saveStack.pop();
          current = state.current;
          currentPos = parserInput.i = state.i;
          j = state.j;
      };
      parserInput.forget = function() {
          saveStack.pop();
      };
      parserInput.isWhitespace = function (offset) {
          var pos = parserInput.i + (offset || 0),
              code = input.charCodeAt(pos);
          return (code === CHARCODE_SPACE || code === CHARCODE_CR || code === CHARCODE_TAB || code === CHARCODE_LF);
      };
  
      // Specialization of $(tok)
      parserInput.$re = function(tok) {
          if (parserInput.i > currentPos) {
              current = current.slice(parserInput.i - currentPos);
              currentPos = parserInput.i;
          }
  
          var m = tok.exec(current);
          if (!m) {
              return null;
          }
  
          skipWhitespace(m[0].length);
          if (typeof m === "string") {
              return m;
          }
  
          return m.length === 1 ? m[0] : m;
      };
  
      parserInput.$char = function(tok) {
          if (input.charAt(parserInput.i) !== tok) {
              return null;
          }
          skipWhitespace(1);
          return tok;
      };
  
      parserInput.$str = function(tok) {
          var tokLength = tok.length;
  
          // https://jsperf.com/string-startswith/21
          for (var i = 0; i < tokLength; i++) {
              if (input.charAt(parserInput.i + i) !== tok.charAt(i)) {
                  return null;
              }
          }
  
          skipWhitespace(tokLength);
          return tok;
      };
  
      parserInput.$quoted = function() {
  
          var startChar = input.charAt(parserInput.i);
          if (startChar !== "'" && startChar !== '"') {
              return;
          }
          var length = input.length,
              currentPosition = parserInput.i;
  
          for (var i = 1; i + currentPosition < length; i++) {
              var nextChar = input.charAt(i + currentPosition);
              switch (nextChar) {
                  case "\\":
                      i++;
                      continue;
                  case "\r":
                  case "\n":
                      break;
                  case startChar:
                      var str = input.substr(currentPosition, i + 1);
                      skipWhitespace(i + 1);
                      return str;
                  default:
              }
          }
          return null;
      };
  
      parserInput.autoCommentAbsorb = true;
      parserInput.commentStore = [];
      parserInput.finished = false;
  
      // Same as $(), but don't change the state of the parser,
      // just return the match.
      parserInput.peek = function(tok) {
          if (typeof tok === 'string') {
              // https://jsperf.com/string-startswith/21
              for (var i = 0; i < tok.length; i++) {
                  if (input.charAt(parserInput.i + i) !== tok.charAt(i)) {
                      return false;
                  }
              }
              return true;
          } else {
              return tok.test(current);
          }
      };
  
      // Specialization of peek()
      // TODO remove or change some currentChar calls to peekChar
      parserInput.peekChar = function(tok) {
          return input.charAt(parserInput.i) === tok;
      };
  
      parserInput.currentChar = function() {
          return input.charAt(parserInput.i);
      };
  
      parserInput.getInput = function() {
          return input;
      };
  
      parserInput.peekNotNumeric = function() {
          var c = input.charCodeAt(parserInput.i);
          // Is the first char of the dimension 0-9, '.', '+' or '-'
          return (c > CHARCODE_9 || c < CHARCODE_PLUS) || c === CHARCODE_FORWARD_SLASH || c === CHARCODE_COMMA;
      };
  
      parserInput.start = function(str, chunkInput, failFunction) {
          input = str;
          parserInput.i = j = currentPos = furthest = 0;
  
          // chunking apparently makes things quicker (but my tests indicate
          // it might actually make things slower in node at least)
          // and it is a non-perfect parse - it can't recognise
          // unquoted urls, meaning it can't distinguish comments
          // meaning comments with quotes or {}() in them get 'counted'
          // and then lead to parse errors.
          // In addition if the chunking chunks in the wrong place we might
          // not be able to parse a parser statement in one go
          // this is officially deprecated but can be switched on via an option
          // in the case it causes too much performance issues.
          if (chunkInput) {
              chunks = chunker(str, failFunction);
          } else {
              chunks = [str];
          }
  
          current = chunks[0];
  
          skipWhitespace(0);
      };
  
      parserInput.end = function() {
          var message,
              isFinished = parserInput.i >= input.length;
  
          if (parserInput.i < furthest) {
              message = furthestPossibleErrorMessage;
              parserInput.i = furthest;
          }
          return {
              isFinished: isFinished,
              furthest: parserInput.i,
              furthestPossibleErrorMessage: message,
              furthestReachedEnd: parserInput.i >= input.length - 1,
              furthestChar: input[parserInput.i]
          };
      };
  
      return parserInput;
  };
  
  },{"./chunker":40}],42:[function(require,module,exports){
  var LessError = require('../less-error'),
      tree = require("../tree"),
      visitors = require("../visitors"),
      getParserInput = require("./parser-input"),
      utils = require("../utils"),
      functionRegistry = require('../functions/function-registry');
  
  //
  // less.js - parser
  //
  //    A relatively straight-forward predictive parser.
  //    There is no tokenization/lexing stage, the input is parsed
  //    in one sweep.
  //
  //    To make the parser fast enough to run in the browser, several
  //    optimization had to be made:
  //
  //    - Matching and slicing on a huge input is often cause of slowdowns.
  //      The solution is to chunkify the input into smaller strings.
  //      The chunks are stored in the `chunks` var,
  //      `j` holds the current chunk index, and `currentPos` holds
  //      the index of the current chunk in relation to `input`.
  //      This gives us an almost 4x speed-up.
  //
  //    - In many cases, we don't need to match individual tokens;
  //      for example, if a value doesn't hold any variables, operations
  //      or dynamic references, the parser can effectively 'skip' it,
  //      treating it as a literal.
  //      An example would be '1px solid #000' - which evaluates to itself,
  //      we don't need to know what the individual components are.
  //      The drawback, of course is that you don't get the benefits of
  //      syntax-checking on the CSS. This gives us a 50% speed-up in the parser,
  //      and a smaller speed-up in the code-gen.
  //
  //
  //    Token matching is done with the `$` function, which either takes
  //    a terminal string or regexp, or a non-terminal function to call.
  //    It also takes care of moving all the indices forwards.
  //
  
  var Parser = function Parser(context, imports, fileInfo) {
      var parsers,
          parserInput = getParserInput();
  
      function error(msg, type) {
          throw new LessError(
              {
                  index: parserInput.i,
                  filename: fileInfo.filename,
                  type: type || 'Syntax',
                  message: msg
              },
              imports
          );
      }
  
      function expect(arg, msg, index) {
          // some older browsers return typeof 'function' for RegExp
          var result = (arg instanceof Function) ? arg.call(parsers) : parserInput.$re(arg);
          if (result) {
              return result;
          }
          error(msg || (typeof arg === 'string' ? "expected '" + arg + "' got '" + parserInput.currentChar() + "'"
                                                 : "unexpected token"));
      }
  
      // Specialization of expect()
      function expectChar(arg, msg) {
          if (parserInput.$char(arg)) {
              return arg;
          }
          error(msg || "expected '" + arg + "' got '" + parserInput.currentChar() + "'");
      }
  
      function getDebugInfo(index) {
          var filename = fileInfo.filename;
  
          return {
              lineNumber: utils.getLocation(index, parserInput.getInput()).line + 1,
              fileName: filename
          };
      }
  
      /**
       *  Used after initial parsing to create nodes on the fly
       * 
       *  @param {String} str          - string to parse 
       *  @param {Array}  parseList    - array of parsers to run input through e.g. ["value", "important"]
       *  @param {Number} currentIndex - start number to begin indexing
       *  @param {Object} fileInfo     - fileInfo to attach to created nodes
       */
      function parseNode(str, parseList, currentIndex, fileInfo, callback) {
          var result, returnNodes = [];
          var parser = parserInput;
  
          try {
              parser.start(str, false, function fail(msg, index) {
                  callback({
                      message: msg,
                      index: index + currentIndex
                  });
              });
              for (var x = 0, p, i; (p = parseList[x]); x++) {
                  i = parser.i;
                  result = parsers[p]();
                  if (result) {
                      result._index = i + currentIndex;
                      result._fileInfo = fileInfo;
                      returnNodes.push(result);
                  }
                  else {
                      returnNodes.push(null);
                  }
              }
  
              var endInfo = parser.end();
              if (endInfo.isFinished) {
                  callback(null, returnNodes);
              }
              else {
                  callback(true, null);
              }
          } catch (e) {
              throw new LessError({
                  index: e.index + currentIndex,
                  message: e.message
              }, imports, fileInfo.filename);
          }
      }
      
      //
      // The Parser
      //
      return {
          parserInput: parserInput,
          imports: imports,
          fileInfo: fileInfo,
          parseNode: parseNode,
          //
          // Parse an input string into an abstract syntax tree,
          // @param str A string containing 'less' markup
          // @param callback call `callback` when done.
          // @param [additionalData] An optional map which can contains vars - a map (key, value) of variables to apply
          //
          parse: function (str, callback, additionalData) {
              var root, error = null, globalVars, modifyVars, ignored, preText = "";
  
              globalVars = (additionalData && additionalData.globalVars) ? Parser.serializeVars(additionalData.globalVars) + '\n' : '';
              modifyVars = (additionalData && additionalData.modifyVars) ? '\n' + Parser.serializeVars(additionalData.modifyVars) : '';
  
              if (context.pluginManager) {
                  var preProcessors = context.pluginManager.getPreProcessors();
                  for (var i = 0; i < preProcessors.length; i++) {
                      str = preProcessors[i].process(str, { context: context, imports: imports, fileInfo: fileInfo });
                  }
              }
  
              if (globalVars || (additionalData && additionalData.banner)) {
                  preText = ((additionalData && additionalData.banner) ? additionalData.banner : "") + globalVars;
                  ignored = imports.contentsIgnoredChars;
                  ignored[fileInfo.filename] = ignored[fileInfo.filename] || 0;
                  ignored[fileInfo.filename] += preText.length;
              }
  
              str = str.replace(/\r\n?/g, '\n');
              // Remove potential UTF Byte Order Mark
              str = preText + str.replace(/^\uFEFF/, '') + modifyVars;
              imports.contents[fileInfo.filename] = str;
  
              // Start with the primary rule.
              // The whole syntax tree is held under a Ruleset node,
              // with the `root` property set to true, so no `{}` are
              // output. The callback is called when the input is parsed.
              try {
                  parserInput.start(str, context.chunkInput, function fail(msg, index) {
                      throw new LessError({
                          index: index,
                          type: 'Parse',
                          message: msg,
                          filename: fileInfo.filename
                      }, imports);
                  });
  
                  tree.Node.prototype.parse = this;
                  root = new tree.Ruleset(null, this.parsers.primary());
                  tree.Node.prototype.rootNode = root;
                  root.root = true;
                  root.firstRoot = true;
                  root.functionRegistry = functionRegistry.inherit();
                  
              } catch (e) {
                  return callback(new LessError(e, imports, fileInfo.filename));
              }
  
              // If `i` is smaller than the `input.length - 1`,
              // it means the parser wasn't able to parse the whole
              // string, so we've got a parsing error.
              //
              // We try to extract a \n delimited string,
              // showing the line where the parse error occurred.
              // We split it up into two parts (the part which parsed,
              // and the part which didn't), so we can color them differently.
              var endInfo = parserInput.end();
              if (!endInfo.isFinished) {
  
                  var message = endInfo.furthestPossibleErrorMessage;
  
                  if (!message) {
                      message = "Unrecognised input";
                      if (endInfo.furthestChar === '}') {
                          message += ". Possibly missing opening '{'";
                      } else if (endInfo.furthestChar === ')') {
                          message += ". Possibly missing opening '('";
                      } else if (endInfo.furthestReachedEnd) {
                          message += ". Possibly missing something";
                      }
                  }
  
                  error = new LessError({
                      type: "Parse",
                      message: message,
                      index: endInfo.furthest,
                      filename: fileInfo.filename
                  }, imports);
              }
  
              var finish = function (e) {
                  e = error || e || imports.error;
  
                  if (e) {
                      if (!(e instanceof LessError)) {
                          e = new LessError(e, imports, fileInfo.filename);
                      }
  
                      return callback(e);
                  }
                  else {
                      return callback(null, root);
                  }
              };
  
              if (context.processImports !== false) {
                  new visitors.ImportVisitor(imports, finish)
                      .run(root);
              } else {
                  return finish();
              }
          },
  
          //
          // Here in, the parsing rules/functions
          //
          // The basic structure of the syntax tree generated is as follows:
          //
          //   Ruleset ->  Declaration -> Value -> Expression -> Entity
          //
          // Here's some Less code:
          //
          //    .class {
          //      color: #fff;
          //      border: 1px solid #000;
          //      width: @w + 4px;
          //      > .child {...}
          //    }
          //
          // And here's what the parse tree might look like:
          //
          //     Ruleset (Selector '.class', [
          //         Declaration ("color",  Value ([Expression [Color #fff]]))
          //         Declaration ("border", Value ([Expression [Dimension 1px][Keyword "solid"][Color #000]]))
          //         Declaration ("width",  Value ([Expression [Operation " + " [Variable "@w"][Dimension 4px]]]))
          //         Ruleset (Selector [Element '>', '.child'], [...])
          //     ])
          //
          //  In general, most rules will try to parse a token with the `$re()` function, and if the return
          //  value is truly, will return a new node, of the relevant type. Sometimes, we need to check
          //  first, before parsing, that's when we use `peek()`.
          //
          parsers: parsers = {
              //
              // The `primary` rule is the *entry* and *exit* point of the parser.
              // The rules here can appear at any level of the parse tree.
              //
              // The recursive nature of the grammar is an interplay between the `block`
              // rule, which represents `{ ... }`, the `ruleset` rule, and this `primary` rule,
              // as represented by this simplified grammar:
              //
              //     primary  →  (ruleset | declaration)+
              //     ruleset  →  selector+ block
              //     block    →  '{' primary '}'
              //
              // Only at one point is the primary rule not called from the
              // block rule: at the root level.
              //
              primary: function () {
                  var mixin = this.mixin, root = [], node;
  
                  while (true) {
                      while (true) {
                          node = this.comment();
                          if (!node) { break; }
                          root.push(node);
                      }
                      // always process comments before deciding if finished
                      if (parserInput.finished) {
                          break;
                      }
                      if (parserInput.peek('}')) {
                          break;
                      }
  
                      node = this.extendRule();
                      if (node) {
                          root = root.concat(node);
                          continue;
                      }
  
                      node = mixin.definition() || this.declaration() || this.ruleset() ||
                          mixin.call() || this.variableCall() || this.entities.call() || this.atrule();
                      if (node) {
                          root.push(node);
                      } else {
                          var foundSemiColon = false;
                          while (parserInput.$char(";")) {
                              foundSemiColon = true;
                          }
                          if (!foundSemiColon) {
                              break;
                          }
                      }
                  }
  
                  return root;
              },
  
              // comments are collected by the main parsing mechanism and then assigned to nodes
              // where the current structure allows it
              comment: function () {
                  if (parserInput.commentStore.length) {
                      var comment = parserInput.commentStore.shift();
                      return new(tree.Comment)(comment.text, comment.isLineComment, comment.index, fileInfo);
                  }
              },
  
              //
              // Entities are tokens which can be found inside an Expression
              //
              entities: {
                  //
                  // A string, which supports escaping " and '
                  //
                  //     "milky way" 'he\'s the one!'
                  //
                  quoted: function () {
                      var str, index = parserInput.i, isEscaped = false;
  
                      parserInput.save();
                      if (parserInput.$char("~")) {
                          isEscaped = true;
                      }
                      str = parserInput.$quoted();
                      if (!str) {
                          parserInput.restore();
                          return;
                      }
                      parserInput.forget();
  
                      return new(tree.Quoted)(str.charAt(0), str.substr(1, str.length - 2), isEscaped, index, fileInfo);
                  },
  
                  //
                  // A catch-all word, such as:
                  //
                  //     black border-collapse
                  //
                  keyword: function () {
                      var k = parserInput.$char("%") || parserInput.$re(/^\[?[_A-Za-z-][_A-Za-z0-9-]*\]?/);
                      if (k) {
                          return tree.Color.fromKeyword(k) || new(tree.Keyword)(k);
                      }
                  },
  
                  //
                  // A function call
                  //
                  //     rgb(255, 0, 255)
                  //
                  // The arguments are parsed with the `entities.arguments` parser.
                  //
                  call: function () {
                      var name, args, func, index = parserInput.i;
  
                      // http://jsperf.com/case-insensitive-regex-vs-strtolower-then-regex/18
                      if (parserInput.peek(/^url\(/i)) {
                          return;
                      }
  
                      parserInput.save();
  
                      name = parserInput.$re(/^([\w-]+|%|progid:[\w\.]+)\(/);
                      if (!name) {
                          parserInput.forget(); 
                          return;
                      }
  
                      name = name[1];
                      func = this.customFuncCall(name);
                      if (func) {
                          args = func.parse();
                          if (args && func.stop) {
                              parserInput.forget();
                              return args;
                          }
                      }
  
                      args = this.arguments(args);
  
                      if (!parserInput.$char(')')) {
                          parserInput.restore("Could not parse call arguments or missing ')'");
                          return;
                      }
  
                      parserInput.forget();
                      
                      return new(tree.Call)(name, args, index, fileInfo);
                  },
                  
                  //
                  // Parsing rules for functions with non-standard args, e.g.:
                  //
                  //     boolean(not(2 > 1))
                  //
                  //     This is a quick prototype, to be modified/improved when
                  //     more custom-parsed funcs come (e.g. `selector(...)`)
                  //
  
                  customFuncCall: function (name) {
                      /* Ideally the table is to be moved out of here for faster perf.,
                         but it's quite tricky since it relies on all these `parsers`
                         and `expect` available only here */
                      return {
                          alpha:   f(parsers.ieAlpha, true),
                          boolean: f(condition),
                          'if':    f(condition)
                      }[name.toLowerCase()];
  
                      function f(parse, stop) {
                          return {
                              parse: parse, // parsing function
                              stop:  stop   // when true - stop after parse() and return its result, 
                                            // otherwise continue for plain args
                          };
                      }
                  
                      function condition() {
                          return [expect(parsers.condition, 'expected condition')];
                      }
                  },
  
                  arguments: function (prevArgs) {
                      var argsComma = prevArgs || [],
                          argsSemiColon = [],
                          isSemiColonSeparated, value;
  
                      parserInput.save();
  
                      while (true) {
                          if (prevArgs) {
                              prevArgs = false;
                          } else {
                              value = parsers.detachedRuleset() || this.assignment() || parsers.expression();
                              if (!value) {
                                  break;
                              }
  
                              if (value.value && value.value.length == 1) {
                                  value = value.value[0];
                              }
  
                              argsComma.push(value);
                          }
  
                          if (parserInput.$char(',')) {
                              continue;
                          }
  
                          if (parserInput.$char(';') || isSemiColonSeparated) {
                              isSemiColonSeparated = true;
                              value = (argsComma.length < 1) ? argsComma[0]
                                  : new tree.Value(argsComma);
                              argsSemiColon.push(value);
                              argsComma = [];
                          }
                      }
  
                      parserInput.forget();
                      return isSemiColonSeparated ? argsSemiColon : argsComma;
                  },
                  literal: function () {
                      return this.dimension() ||
                             this.color() ||
                             this.quoted() ||
                             this.unicodeDescriptor();
                  },
  
                  // Assignments are argument entities for calls.
                  // They are present in ie filter properties as shown below.
                  //
                  //     filter: progid:DXImageTransform.Microsoft.Alpha( *opacity=50* )
                  //
  
                  assignment: function () {
                      var key, value;
                      parserInput.save();
                      key = parserInput.$re(/^\w+(?=\s?=)/i);
                      if (!key) {
                          parserInput.restore();
                          return;
                      }
                      if (!parserInput.$char('=')) {
                          parserInput.restore();
                          return;
                      }
                      value = parsers.entity();
                      if (value) {
                          parserInput.forget();
                          return new(tree.Assignment)(key, value);
                      } else {
                          parserInput.restore();
                      }
                  },
  
                  //
                  // Parse url() tokens
                  //
                  // We use a specific rule for urls, because they don't really behave like
                  // standard function calls. The difference is that the argument doesn't have
                  // to be enclosed within a string, so it can't be parsed as an Expression.
                  //
                  url: function () {
                      var value, index = parserInput.i;
  
                      parserInput.autoCommentAbsorb = false;
  
                      if (!parserInput.$str("url(")) {
                          parserInput.autoCommentAbsorb = true;
                          return;
                      }
  
                      value = this.quoted() || this.variable() || this.property() ||
                              parserInput.$re(/^(?:(?:\\[\(\)'"])|[^\(\)'"])+/) || "";
  
                      parserInput.autoCommentAbsorb = true;
  
                      expectChar(')');
  
                      return new(tree.URL)((value.value != null || 
                          value instanceof tree.Variable || 
                          value instanceof tree.Property) ?
                          value : new(tree.Anonymous)(value, index), index, fileInfo);
                  },
  
                  //
                  // A Variable entity, such as `@fink`, in
                  //
                  //     width: @fink + 2px
                  //
                  // We use a different parser for variable definitions,
                  // see `parsers.variable`.
                  //
                  variable: function () {
                      var name, index = parserInput.i;
  
                      if (parserInput.currentChar() === '@' && (name = parserInput.$re(/^@@?[\w-]+/))) {
                          return new(tree.Variable)(name, index, fileInfo);
                      }
                  },
  
                  // A variable entity using the protective {} e.g. @{var}
                  variableCurly: function () {
                      var curly, index = parserInput.i;
  
                      if (parserInput.currentChar() === '@' && (curly = parserInput.$re(/^@\{([\w-]+)\}/))) {
                          return new(tree.Variable)("@" + curly[1], index, fileInfo);
                      }
                  },
                  //
                  // A Property accessor, such as `$color`, in
                  //
                  //     background-color: $color
                  //
                  property: function () {
                      var name, index = parserInput.i;
  
                      if (parserInput.currentChar() === '$' && (name = parserInput.$re(/^\$[\w-]+/))) {
                          return new(tree.Property)(name, index, fileInfo);
                      }
                  },
  
                  // A property entity useing the protective {} e.g. ${prop}
                  propertyCurly: function () {
                      var curly, index = parserInput.i;
  
                      if (parserInput.currentChar() === '$' && (curly = parserInput.$re(/^\$\{([\w-]+)\}/))) {
                          return new(tree.Property)("$" + curly[1], index, fileInfo);
                      }
                  },
                  //
                  // A Hexadecimal color
                  //
                  //     #4F3C2F
                  //
                  // `rgb` and `hsl` colors are parsed through the `entities.call` parser.
                  //
                  color: function () {
                      var rgb;
  
                      if (parserInput.currentChar() === '#' && (rgb = parserInput.$re(/^#([A-Fa-f0-9]{6}|[A-Fa-f0-9]{3})/))) {
                          // strip colons, brackets, whitespaces and other characters that should not
                          // definitely be part of color string
                          var colorCandidateString = rgb.input.match(/^#([\w]+).*/);
                          colorCandidateString = colorCandidateString[1];
                          if (!colorCandidateString.match(/^[A-Fa-f0-9]+$/)) { // verify if candidate consists only of allowed HEX characters
                              error("Invalid HEX color code");
                          }
                          return new(tree.Color)(rgb[1], undefined, '#' + colorCandidateString);
                      }
                  },
  
                  colorKeyword: function () {
                      parserInput.save();
                      var autoCommentAbsorb = parserInput.autoCommentAbsorb;
                      parserInput.autoCommentAbsorb = false;
                      var k = parserInput.$re(/^[_A-Za-z-][_A-Za-z0-9-]+/);
                      parserInput.autoCommentAbsorb = autoCommentAbsorb;
                      if (!k) {
                          parserInput.forget();
                          return;
                      }
                      parserInput.restore();
                      var color = tree.Color.fromKeyword(k);
                      if (color) {
                          parserInput.$str(k);
                          return color;
                      }
                  },
  
                  //
                  // A Dimension, that is, a number and a unit
                  //
                  //     0.5em 95%
                  //
                  dimension: function () {
                      if (parserInput.peekNotNumeric()) {
                          return;
                      }
  
                      var value = parserInput.$re(/^([+-]?\d*\.?\d+)(%|[a-z_]+)?/i);
                      if (value) {
                          return new(tree.Dimension)(value[1], value[2]);
                      }
                  },
  
                  //
                  // A unicode descriptor, as is used in unicode-range
                  //
                  // U+0??  or U+00A1-00A9
                  //
                  unicodeDescriptor: function () {
                      var ud;
  
                      ud = parserInput.$re(/^U\+[0-9a-fA-F?]+(\-[0-9a-fA-F?]+)?/);
                      if (ud) {
                          return new(tree.UnicodeDescriptor)(ud[0]);
                      }
                  },
  
                  //
                  // JavaScript code to be evaluated
                  //
                  //     `window.location.href`
                  //
                  javascript: function () {
                      var js, index = parserInput.i;
  
                      parserInput.save();
  
                      var escape = parserInput.$char("~");
                      var jsQuote = parserInput.$char("`");
  
                      if (!jsQuote) {
                          parserInput.restore();
                          return;
                      }
  
                      js = parserInput.$re(/^[^`]*`/);
                      if (js) {
                          parserInput.forget();
                          return new(tree.JavaScript)(js.substr(0, js.length - 1), Boolean(escape), index, fileInfo);
                      }
                      parserInput.restore("invalid javascript definition");
                  }
              },
  
              //
              // The variable part of a variable definition. Used in the `rule` parser
              //
              //     @fink:
              //
              variable: function () {
                  var name;
  
                  if (parserInput.currentChar() === '@' && (name = parserInput.$re(/^(@[\w-]+)\s*:/))) { return name[1]; }
              },
  
              //
              // Call a variable value
              //
              //     @fink()
              //
              variableCall: function () {
                  var name;
  
                  if (parserInput.currentChar() === '@'
                      && (name = parserInput.$re(/^(@[\w-]+)\(\s*\)/))
                      && parsers.end()) {
                      return new tree.VariableCall(name[1]);
                  }
              },
  
              //
              // extend syntax - used to extend selectors
              //
              extend: function(isRule) {
                  var elements, e, index = parserInput.i, option, extendList, extend;
  
                  if (!parserInput.$str(isRule ? "&:extend(" : ":extend(")) {
                      return;
                  }
  
                  do {
                      option = null;
                      elements = null;
                      while (!(option = parserInput.$re(/^(all)(?=\s*(\)|,))/))) {
                          e = this.element();
                          if (!e) {
                              break;
                          }
                          if (elements) {
                              elements.push(e);
                          } else {
                              elements = [ e ];
                          }
                      }
  
                      option = option && option[1];
                      if (!elements) {
                          error("Missing target selector for :extend().");
                      }
                      extend = new(tree.Extend)(new(tree.Selector)(elements), option, index, fileInfo);
                      if (extendList) {
                          extendList.push(extend);
                      } else {
                          extendList = [ extend ];
                      }
                  } while (parserInput.$char(","));
  
                  expect(/^\)/);
  
                  if (isRule) {
                      expect(/^;/);
                  }
  
                  return extendList;
              },
  
              //
              // extendRule - used in a rule to extend all the parent selectors
              //
              extendRule: function() {
                  return this.extend(true);
              },
  
              //
              // Mixins
              //
              mixin: {
                  //
                  // A Mixin call, with an optional argument list
                  //
                  //     #mixins > .square(#fff);
                  //     .rounded(4px, black);
                  //     .button;
                  //
                  // The `while` loop is there because mixins can be
                  // namespaced, but we only support the child and descendant
                  // selector for now.
                  //
                  call: function () {
                      var s = parserInput.currentChar(), important = false, index = parserInput.i, elemIndex,
                          elements, elem, e, c, args;
  
                      if (s !== '.' && s !== '#') { return; }
  
                      parserInput.save(); // stop us absorbing part of an invalid selector
  
                      while (true) {
                          elemIndex = parserInput.i;
                          e = parserInput.$re(/^[#.](?:[\w-]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+/);
                          if (!e) {
                              break;
                          }
                          elem = new(tree.Element)(c, e, elemIndex, fileInfo);
                          if (elements) {
                              elements.push(elem);
                          } else {
                              elements = [ elem ];
                          }
                          c = parserInput.$char('>');
                      }
  
                      if (elements) {
                          if (parserInput.$char('(')) {
                              args = this.args(true).args;
                              expectChar(')');
                          }
  
                          if (parsers.important()) {
                              important = true;
                          }
  
                          if (parsers.end()) {
                              parserInput.forget();
                              return new(tree.mixin.Call)(elements, args, index, fileInfo, important);
                          }
                      }
  
                      parserInput.restore();
                  },
                  args: function (isCall) {
                      var entities = parsers.entities,
                          returner = { args:null, variadic: false },
                          expressions = [], argsSemiColon = [], argsComma = [],
                          isSemiColonSeparated, expressionContainsNamed, name, nameLoop,
                          value, arg, expand;
  
                      parserInput.save();
  
                      while (true) {
                          if (isCall) {
                              arg = parsers.detachedRuleset() || parsers.expression();
                          } else {
                              parserInput.commentStore.length = 0;
                              if (parserInput.$str("...")) {
                                  returner.variadic = true;
                                  if (parserInput.$char(";") && !isSemiColonSeparated) {
                                      isSemiColonSeparated = true;
                                  }
                                  (isSemiColonSeparated ? argsSemiColon : argsComma)
                                      .push({ variadic: true });
                                  break;
                              }
                              arg = entities.variable() || entities.property() || entities.literal() || entities.keyword();
                          }
  
                          if (!arg) {
                              break;
                          }
  
                          nameLoop = null;
                          if (arg.throwAwayComments) {
                              arg.throwAwayComments();
                          }
                          value = arg;
                          var val = null;
  
                          if (isCall) {
                              // Variable
                              if (arg.value && arg.value.length == 1) {
                                  val = arg.value[0];
                              }
                          } else {
                              val = arg;
                          }
  
                          if (val && (val instanceof tree.Variable || val instanceof tree.Property)) {
                              if (parserInput.$char(':')) {
                                  if (expressions.length > 0) {
                                      if (isSemiColonSeparated) {
                                          error("Cannot mix ; and , as delimiter types");
                                      }
                                      expressionContainsNamed = true;
                                  }
  
                                  value = parsers.detachedRuleset() || parsers.expression();
  
                                  if (!value) {
                                      if (isCall) {
                                          error("could not understand value for named argument");
                                      } else {
                                          parserInput.restore();
                                          returner.args = [];
                                          return returner;
                                      }
                                  }
                                  nameLoop = (name = val.name);
                              } else if (parserInput.$str("...")) {
                                  if (!isCall) {
                                      returner.variadic = true;
                                      if (parserInput.$char(";") && !isSemiColonSeparated) {
                                          isSemiColonSeparated = true;
                                      }
                                      (isSemiColonSeparated ? argsSemiColon : argsComma)
                                          .push({ name: arg.name, variadic: true });
                                      break;
                                  } else {
                                      expand = true;
                                  }
                              } else if (!isCall) {
                                  name = nameLoop = val.name;
                                  value = null;
                              }
                          }
  
                          if (value) {
                              expressions.push(value);
                          }
  
                          argsComma.push({ name:nameLoop, value:value, expand:expand });
  
                          if (parserInput.$char(',')) {
                              continue;
                          }
  
                          if (parserInput.$char(';') || isSemiColonSeparated) {
  
                              if (expressionContainsNamed) {
                                  error("Cannot mix ; and , as delimiter types");
                              }
  
                              isSemiColonSeparated = true;
  
                              if (expressions.length > 1) {
                                  value = new(tree.Value)(expressions);
                              }
                              argsSemiColon.push({ name:name, value:value, expand:expand });
  
                              name = null;
                              expressions = [];
                              expressionContainsNamed = false;
                          }
                      }
  
                      parserInput.forget();
                      returner.args = isSemiColonSeparated ? argsSemiColon : argsComma;
                      return returner;
                  },
                  //
                  // A Mixin definition, with a list of parameters
                  //
                  //     .rounded (@radius: 2px, @color) {
                  //        ...
                  //     }
                  //
                  // Until we have a finer grained state-machine, we have to
                  // do a look-ahead, to make sure we don't have a mixin call.
                  // See the `rule` function for more information.
                  //
                  // We start by matching `.rounded (`, and then proceed on to
                  // the argument list, which has optional default values.
                  // We store the parameters in `params`, with a `value` key,
                  // if there is a value, such as in the case of `@radius`.
                  //
                  // Once we've got our params list, and a closing `)`, we parse
                  // the `{...}` block.
                  //
                  definition: function () {
                      var name, params = [], match, ruleset, cond, variadic = false;
                      if ((parserInput.currentChar() !== '.' && parserInput.currentChar() !== '#') ||
                          parserInput.peek(/^[^{]*\}/)) {
                          return;
                      }
  
                      parserInput.save();
  
                      match = parserInput.$re(/^([#.](?:[\w-]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+)\s*\(/);
                      if (match) {
                          name = match[1];
  
                          var argInfo = this.args(false);
                          params = argInfo.args;
                          variadic = argInfo.variadic;
  
                          // .mixincall("@{a}");
                          // looks a bit like a mixin definition..
                          // also
                          // .mixincall(@a: {rule: set;});
                          // so we have to be nice and restore
                          if (!parserInput.$char(')')) {
                              parserInput.restore("Missing closing ')'");
                              return;
                          }
  
                          parserInput.commentStore.length = 0;
  
                          if (parserInput.$str("when")) { // Guard
                              cond = expect(parsers.conditions, 'expected condition');
                          }
  
                          ruleset = parsers.block();
  
                          if (ruleset) {
                              parserInput.forget();
                              return new(tree.mixin.Definition)(name, params, ruleset, cond, variadic);
                          } else {
                              parserInput.restore();
                          }
                      } else {
                          parserInput.forget();
                      }
                  }
              },
  
              //
              // Entities are the smallest recognized token,
              // and can be found inside a rule's value.
              //
              entity: function () {
                  var entities = this.entities;
  
                  return this.comment() || entities.literal() || entities.variable() || entities.url() ||
                         entities.property() || entities.call() || entities.keyword()  || entities.javascript();
              },
  
              //
              // A Declaration terminator. Note that we use `peek()` to check for '}',
              // because the `block` rule will be expecting it, but we still need to make sure
              // it's there, if ';' was omitted.
              //
              end: function () {
                  return parserInput.$char(';') || parserInput.peek('}');
              },
  
              //
              // IE's alpha function
              //
              //     alpha(opacity=88)
              //
              ieAlpha: function () {
                  var value;
  
                  // http://jsperf.com/case-insensitive-regex-vs-strtolower-then-regex/18
                  if (!parserInput.$re(/^opacity=/i)) { return; }
                  value = parserInput.$re(/^\d+/);
                  if (!value) {
                      value = expect(parsers.entities.variable, "Could not parse alpha");
                      value = '@{' + value.name.slice(1) + '}';
                  }
                  expectChar(')');
                  return new tree.Quoted('', 'alpha(opacity=' + value + ')');
              },
  
              //
              // A Selector Element
              //
              //     div
              //     + h1
              //     #socks
              //     input[type="text"]
              //
              // Elements are the building blocks for Selectors,
              // they are made out of a `Combinator` (see combinator rule),
              // and an element name, such as a tag a class, or `*`.
              //
              element: function () {
                  var e, c, v, index = parserInput.i;
  
                  c = this.combinator();
  
                  e = parserInput.$re(/^(?:\d+\.\d+|\d+)%/) ||
                      parserInput.$re(/^(?:[.#]?|:*)(?:[\w-]|[^\x00-\x9f]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+/) ||
                      parserInput.$char('*') || parserInput.$char('&') || this.attribute() ||
                      parserInput.$re(/^\([^&()@]+\)/) ||  parserInput.$re(/^[\.#:](?=@)/) ||
                      this.entities.variableCurly();
  
                  if (!e) {
                      parserInput.save();
                      if (parserInput.$char('(')) {
                          if ((v = this.selector(false)) && parserInput.$char(')')) {
                              e = new(tree.Paren)(v);
                              parserInput.forget();
                          } else {
                              parserInput.restore("Missing closing ')'");
                          }
                      } else {
                          parserInput.forget();
                      }
                  }
  
                  if (e) { return new(tree.Element)(c, e, index, fileInfo); }
              },
  
              //
              // Combinators combine elements together, in a Selector.
              //
              // Because our parser isn't white-space sensitive, special care
              // has to be taken, when parsing the descendant combinator, ` `,
              // as it's an empty space. We have to check the previous character
              // in the input, to see if it's a ` ` character. More info on how
              // we deal with this in *combinator.js*.
              //
              combinator: function () {
                  var c = parserInput.currentChar();
  
                  if (c === '/') {
                      parserInput.save();
                      var slashedCombinator = parserInput.$re(/^\/[a-z]+\//i);
                      if (slashedCombinator) {
                          parserInput.forget();
                          return new(tree.Combinator)(slashedCombinator);
                      }
                      parserInput.restore();
                  }
  
                  if (c === '>' || c === '+' || c === '~' || c === '|' || c === '^') {
                      parserInput.i++;
                      if (c === '^' && parserInput.currentChar() === '^') {
                          c = '^^';
                          parserInput.i++;
                      }
                      while (parserInput.isWhitespace()) { parserInput.i++; }
                      return new(tree.Combinator)(c);
                  } else if (parserInput.isWhitespace(-1)) {
                      return new(tree.Combinator)(" ");
                  } else {
                      return new(tree.Combinator)(null);
                  }
              },
              //
              // A CSS Selector
              // with less extensions e.g. the ability to extend and guard
              //
              //     .class > div + h1
              //     li a:hover
              //
              // Selectors are made out of one or more Elements, see above.
              //
              selector: function (isLess) {
                  var index = parserInput.i, elements, extendList, c, e, allExtends, when, condition;
                  isLess = isLess !== false;
                  while ((isLess && (extendList = this.extend())) || (isLess && (when = parserInput.$str("when"))) || (e = this.element())) {
                      if (when) {
                          condition = expect(this.conditions, 'expected condition');
                      } else if (condition) {
                          error("CSS guard can only be used at the end of selector");
                      } else if (extendList) {
                          if (allExtends) {
                              allExtends = allExtends.concat(extendList);
                          } else {
                              allExtends = extendList;
                          }
                      } else {
                          if (allExtends) { error("Extend can only be used at the end of selector"); }
                          c = parserInput.currentChar();
                          if (elements) {
                              elements.push(e);
                          } else {
                              elements = [ e ];
                          }
                          e = null;
                      }
                      if (c === '{' || c === '}' || c === ';' || c === ',' || c === ')') {
                          break;
                      }
                  }
  
                  if (elements) { return new(tree.Selector)(elements, allExtends, condition, index, fileInfo); }
                  if (allExtends) { error("Extend must be used to extend a selector, it cannot be used on its own"); }
              },
              attribute: function () {
                  if (!parserInput.$char('[')) { return; }
  
                  var entities = this.entities,
                      key, val, op;
  
                  if (!(key = entities.variableCurly())) {
                      key = expect(/^(?:[_A-Za-z0-9-\*]*\|)?(?:[_A-Za-z0-9-]|\\.)+/);
                  }
  
                  op = parserInput.$re(/^[|~*$^]?=/);
                  if (op) {
                      val = entities.quoted() || parserInput.$re(/^[0-9]+%/) || parserInput.$re(/^[\w-]+/) || entities.variableCurly();
                  }
  
                  expectChar(']');
  
                  return new(tree.Attribute)(key, op, val);
              },
  
              //
              // The `block` rule is used by `ruleset` and `mixin.definition`.
              // It's a wrapper around the `primary` rule, with added `{}`.
              //
              block: function () {
                  var content;
                  if (parserInput.$char('{') && (content = this.primary()) && parserInput.$char('}')) {
                      return content;
                  }
              },
  
              blockRuleset: function() {
                  var block = this.block();
  
                  if (block) {
                      block = new tree.Ruleset(null, block);
                  }
                  return block;
              },
  
              detachedRuleset: function() {
                  var blockRuleset = this.blockRuleset();
                  if (blockRuleset) {
                      return new tree.DetachedRuleset(blockRuleset);
                  }
              },
  
              //
              // div, .class, body > p {...}
              //
              ruleset: function () {
                  var selectors, s, rules, debugInfo;
  
                  parserInput.save();
  
                  if (context.dumpLineNumbers) {
                      debugInfo = getDebugInfo(parserInput.i);
                  }
  
                  while (true) {
                      s = this.selector();
                      if (!s) {
                          break;
                      }
                      if (selectors) {
                          selectors.push(s);
                      } else {
                          selectors = [ s ];
                      }
                      parserInput.commentStore.length = 0;
                      if (s.condition && selectors.length > 1) {
                          error("Guards are only currently allowed on a single selector.");
                      }
                      if (!parserInput.$char(',')) { break; }
                      if (s.condition) {
                          error("Guards are only currently allowed on a single selector.");
                      }
                      parserInput.commentStore.length = 0;
                  }
  
                  if (selectors && (rules = this.block())) {
                      parserInput.forget();
                      var ruleset = new(tree.Ruleset)(selectors, rules, context.strictImports);
                      if (context.dumpLineNumbers) {
                          ruleset.debugInfo = debugInfo;
                      }
                      return ruleset;
                  } else {
                      parserInput.restore();
                  }
              },
              declaration: function () {
                  var name, value, startOfRule = parserInput.i, c = parserInput.currentChar(), important, merge, isVariable;
  
                  if (c === '.' || c === '#' || c === '&' || c === ':') { return; }
  
                  parserInput.save();
  
                  name = this.variable() || this.ruleProperty();
                  if (name) {
                      isVariable = typeof name === "string";
  
                      if (isVariable) {
                          value = this.detachedRuleset();
                      }
  
                      parserInput.commentStore.length = 0;
                      if (!value) {
                          // a name returned by this.ruleProperty() is always an array of the form:
                          // [string-1, ..., string-n, ""] or [string-1, ..., string-n, "+"]
                          // where each item is a tree.Keyword or tree.Variable
                          merge = !isVariable && name.length > 1 && name.pop().value;
  
                          // Try to store values as anonymous
                          // If we need the value later we'll re-parse it in ruleset.parseValue
                          value = this.anonymousValue();
                          if (value) {
                              parserInput.forget();
                              // anonymous values absorb the end ';' which is required for them to work
                              return new (tree.Declaration)(name, value, false, merge, startOfRule, fileInfo);
                          }
  
                          if (!value) {
                              value = this.value();
                          }
  
                          important = this.important();
                      }
  
                      if (value && this.end()) {
                          parserInput.forget();
                          return new (tree.Declaration)(name, value, important, merge, startOfRule, fileInfo);
                      }
                      else {
                          parserInput.restore();
                      }
                  } else {
                      parserInput.restore();
                  }
              },
              anonymousValue: function () {
                  var index = parserInput.i;
                  var match = parserInput.$re(/^([^@\$+\/'"*`(;{}-]*);/);
                  if (match) {
                      return new(tree.Anonymous)(match[1], index);
                  }
              },
  
              //
              // An @import atrule
              //
              //     @import "lib";
              //
              // Depending on our environment, importing is done differently:
              // In the browser, it's an XHR request, in Node, it would be a
              // file-system operation. The function used for importing is
              // stored in `import`, which we pass to the Import constructor.
              //
              "import": function () {
                  var path, features, index = parserInput.i;
  
                  var dir = parserInput.$re(/^@import?\s+/);
  
                  if (dir) {
                      var options = (dir ? this.importOptions() : null) || {};
  
                      if ((path = this.entities.quoted() || this.entities.url())) {
                          features = this.mediaFeatures();
  
                          if (!parserInput.$char(';')) {
                              parserInput.i = index;
                              error("missing semi-colon or unrecognised media features on import");
                          }
                          features = features && new(tree.Value)(features);
                          return new(tree.Import)(path, features, options, index, fileInfo);
                      }
                      else {
                          parserInput.i = index;
                          error("malformed import statement");
                      }
                  }
              },
  
              importOptions: function() {
                  var o, options = {}, optionName, value;
  
                  // list of options, surrounded by parens
                  if (!parserInput.$char('(')) { return null; }
                  do {
                      o = this.importOption();
                      if (o) {
                          optionName = o;
                          value = true;
                          switch (optionName) {
                              case "css":
                                  optionName = "less";
                                  value = false;
                                  break;
                              case "once":
                                  optionName = "multiple";
                                  value = false;
                                  break;
                          }
                          options[optionName] = value;
                          if (!parserInput.$char(',')) { break; }
                      }
                  } while (o);
                  expectChar(')');
                  return options;
              },
  
              importOption: function() {
                  var opt = parserInput.$re(/^(less|css|multiple|once|inline|reference|optional)/);
                  if (opt) {
                      return opt[1];
                  }
              },
  
              mediaFeature: function () {
                  var entities = this.entities, nodes = [], e, p;
                  parserInput.save();
                  do {
                      e = entities.keyword() || entities.variable();
                      if (e) {
                          nodes.push(e);
                      } else if (parserInput.$char('(')) {
                          p = this.property();
                          e = this.value();
                          if (parserInput.$char(')')) {
                              if (p && e) {
                                  nodes.push(new(tree.Paren)(new(tree.Declaration)(p, e, null, null, parserInput.i, fileInfo, true)));
                              } else if (e) {
                                  nodes.push(new(tree.Paren)(e));
                              } else {
                                  error("badly formed media feature definition");
                              }
                          } else {
                              error("Missing closing ')'", "Parse");
                          }
                      }
                  } while (e);
  
                  parserInput.forget();
                  if (nodes.length > 0) {
                      return new(tree.Expression)(nodes);
                  }
              },
  
              mediaFeatures: function () {
                  var entities = this.entities, features = [], e;
                  do {
                      e = this.mediaFeature();
                      if (e) {
                          features.push(e);
                          if (!parserInput.$char(',')) { break; }
                      } else {
                          e = entities.variable();
                          if (e) {
                              features.push(e);
                              if (!parserInput.$char(',')) { break; }
                          }
                      }
                  } while (e);
  
                  return features.length > 0 ? features : null;
              },
  
              media: function () {
                  var features, rules, media, debugInfo, index = parserInput.i;
  
                  if (context.dumpLineNumbers) {
                      debugInfo = getDebugInfo(index);
                  }
  
                  parserInput.save();
  
                  if (parserInput.$str("@media")) {
                      features = this.mediaFeatures();
  
                      rules = this.block();
  
                      if (!rules) {
                          error("media definitions require block statements after any features");
                      }
  
                      parserInput.forget();
  
                      media = new(tree.Media)(rules, features, index, fileInfo);
                      if (context.dumpLineNumbers) {
                          media.debugInfo = debugInfo;
                      }
  
                      return media;
                  }
  
                  parserInput.restore();
              },
  
              //
  
              // A @plugin directive, used to import plugins dynamically.
              //
              //     @plugin (args) "lib";
              //
              plugin: function () {
                  var path, args, options,
                      index = parserInput.i,
                      dir   = parserInput.$re(/^@plugin?\s+/);
  
                  if (dir) {
                      args = this.pluginArgs();
  
                      if (args) {
                          options = {
                              pluginArgs: args,
                              isPlugin: true
                          };
                      }
                      else {
                          options = { isPlugin: true };
                      }
  
                      if ((path = this.entities.quoted() || this.entities.url())) {
  
                          if (!parserInput.$char(';')) {
                              parserInput.i = index;
                              error("missing semi-colon on @plugin");
                          }
                          return new(tree.Import)(path, null, options, index, fileInfo);
                      }
                      else {
                          parserInput.i = index;
                          error("malformed @plugin statement");
                      }
                  }
              },
  
              pluginArgs: function() {
                  // list of options, surrounded by parens
                  parserInput.save();
                  if (!parserInput.$char('(')) {
                      parserInput.restore();
                      return null;
                  }
                  var args = parserInput.$re(/^\s*([^\);]+)\)\s*/);
                  if (args[1]) {
                      parserInput.forget();
                      return args[1].trim();
                  }
                  else { 
                      parserInput.restore();
                      return null;
                  }
              },
  
              //
              // A CSS AtRule
              //
              //     @charset "utf-8";
              //
              atrule: function () {
                  var index = parserInput.i, name, value, rules, nonVendorSpecificName,
                      hasIdentifier, hasExpression, hasUnknown, hasBlock = true, isRooted = true;
  
                  if (parserInput.currentChar() !== '@') { return; }
  
                  value = this['import']() || this.plugin() || this.media();
                  if (value) {
                      return value;
                  }
  
                  parserInput.save();
  
                  name = parserInput.$re(/^@[a-z-]+/);
  
                  if (!name) { return; }
  
                  nonVendorSpecificName = name;
                  if (name.charAt(1) == '-' && name.indexOf('-', 2) > 0) {
                      nonVendorSpecificName = "@" + name.slice(name.indexOf('-', 2) + 1);
                  }
  
                  switch (nonVendorSpecificName) {
                      case "@charset":
                          hasIdentifier = true;
                          hasBlock = false;
                          break;
                      case "@namespace":
                          hasExpression = true;
                          hasBlock = false;
                          break;
                      case "@keyframes":
                      case "@counter-style":
                          hasIdentifier = true;
                          break;
                      case "@document":
                      case "@supports":
                          hasUnknown = true;
                          isRooted = false;
                          break;
                      default:
                          hasUnknown = true;
                          break;
                  }
  
                  parserInput.commentStore.length = 0;
  
                  if (hasIdentifier) {
                      value = this.entity();
                      if (!value) {
                          error("expected " + name + " identifier");
                      }
                  } else if (hasExpression) {
                      value = this.expression();
                      if (!value) {
                          error("expected " + name + " expression");
                      }
                  } else if (hasUnknown) {
                      value = (parserInput.$re(/^[^{;]+/) || '').trim();
                      hasBlock = (parserInput.currentChar() == '{');
                      if (value) {
                          value = new(tree.Anonymous)(value);
                      }
                  }
  
                  if (hasBlock) {
                      rules = this.blockRuleset();
                  }
  
                  if (rules || (!hasBlock && value && parserInput.$char(';'))) {
                      parserInput.forget();
                      return new (tree.AtRule)(name, value, rules, index, fileInfo,
                          context.dumpLineNumbers ? getDebugInfo(index) : null,
                          isRooted
                      );
                  }
  
                  parserInput.restore("at-rule options not recognised");
              },
  
              //
              // A Value is a comma-delimited list of Expressions
              //
              //     font-family: Baskerville, Georgia, serif;
              //
              // In a Rule, a Value represents everything after the `:`,
              // and before the `;`.
              //
              value: function () {
                  var e, expressions = [], index = parserInput.i;
  
                  do {
                      e = this.expression();
                      if (e) {
                          expressions.push(e);
                          if (!parserInput.$char(',')) { break; }
                      }
                  } while (e);
  
                  if (expressions.length > 0) {
                      return new(tree.Value)(expressions, index);
                  }
              },
              important: function () {
                  if (parserInput.currentChar() === '!') {
                      return parserInput.$re(/^! *important/);
                  }
              },
              sub: function () {
                  var a, e;
  
                  parserInput.save();
                  if (parserInput.$char('(')) {
                      a = this.addition();
                      if (a && parserInput.$char(')')) {
                          parserInput.forget();
                          e = new(tree.Expression)([a]);
                          e.parens = true;
                          return e;
                      }
                      parserInput.restore("Expected ')'");
                      return;
                  }
                  parserInput.restore();
              },
              multiplication: function () {
                  var m, a, op, operation, isSpaced;
                  m = this.operand();
                  if (m) {
                      isSpaced = parserInput.isWhitespace(-1);
                      while (true) {
                          if (parserInput.peek(/^\/[*\/]/)) {
                              break;
                          }
  
                          parserInput.save();
  
                          op = parserInput.$char('/') || parserInput.$char('*');
  
                          if (!op) { parserInput.forget(); break; }
  
                          a = this.operand();
  
                          if (!a) { parserInput.restore(); break; }
                          parserInput.forget();
  
                          m.parensInOp = true;
                          a.parensInOp = true;
                          operation = new(tree.Operation)(op, [operation || m, a], isSpaced);
                          isSpaced = parserInput.isWhitespace(-1);
                      }
                      return operation || m;
                  }
              },
              addition: function () {
                  var m, a, op, operation, isSpaced;
                  m = this.multiplication();
                  if (m) {
                      isSpaced = parserInput.isWhitespace(-1);
                      while (true) {
                          op = parserInput.$re(/^[-+]\s+/) || (!isSpaced && (parserInput.$char('+') || parserInput.$char('-')));
                          if (!op) {
                              break;
                          }
                          a = this.multiplication();
                          if (!a) {
                              break;
                          }
  
                          m.parensInOp = true;
                          a.parensInOp = true;
                          operation = new(tree.Operation)(op, [operation || m, a], isSpaced);
                          isSpaced = parserInput.isWhitespace(-1);
                      }
                      return operation || m;
                  }
              },
              conditions: function () {
                  var a, b, index = parserInput.i, condition;
  
                  a = this.condition();
                  if (a) {
                      while (true) {
                          if (!parserInput.peek(/^,\s*(not\s*)?\(/) || !parserInput.$char(',')) {
                              break;
                          }
                          b = this.condition();
                          if (!b) {
                              break;
                          }
                          condition = new(tree.Condition)('or', condition || a, b, index);
                      }
                      return condition || a;
                  }
              },
              condition: function () {
                  var result, logical, next;
                  function or() {
                      return parserInput.$str("or");
                  }
  
                  result = this.conditionAnd(this);
                  if (!result) {
                      return ;
                  }
                  logical = or();
                  if (logical) {
                      next = this.condition();
                      if (next) {
                          result = new(tree.Condition)(logical, result, next);
                      } else {
                          return ;
                      }
                  }
                  return result;
              },
              conditionAnd: function () {
                  var result, logical, next;
                  function insideCondition(me) {
                      return me.negatedCondition() || me.parenthesisCondition();
                  }
                  function and() {
                      return parserInput.$str("and");
                  }
  
                  result = insideCondition(this);
                  if (!result) {
                      return ;
                  }
                  logical = and();
                  if (logical) {
                      next = this.conditionAnd();
                      if (next) {
                          result = new(tree.Condition)(logical, result, next);
                      } else {
                          return ;
                      }
                  }
                  return result;
              },
              negatedCondition: function () {
                  if (parserInput.$str("not")) {
                      var result = this.parenthesisCondition();
                      if (result) {
                          result.negate = !result.negate;
                      }
                      return result;
                  }
              },
              parenthesisCondition: function () {
                  function tryConditionFollowedByParenthesis(me) {
                      var body;
                      parserInput.save();
                      body = me.condition();
                      if (!body) {
                          parserInput.restore();
                          return ;
                      }
                      if (!parserInput.$char(')')) {
                          parserInput.restore();
                          return ;
                      }
                      parserInput.forget();
                      return body;
                  }
  
                  var body;
                  parserInput.save();
                  if (!parserInput.$str("(")) {
                      parserInput.restore();
                      return ;
                  }
                  body = tryConditionFollowedByParenthesis(this);
                  if (body) {
                      parserInput.forget();
                      return body;
                  }
  
                  body = this.atomicCondition();
                  if (!body) {
                      parserInput.restore();
                      return ;
                  }
                  if (!parserInput.$char(')')) {
                      parserInput.restore("expected ')' got '" + parserInput.currentChar() + "'");
                      return ;
                  }
                  parserInput.forget();
                  return body;
              },
              atomicCondition: function () {
                  var entities = this.entities, index = parserInput.i, a, b, c, op;
  
                  a = this.addition() || entities.keyword() || entities.quoted();
                  if (a) {
                      if (parserInput.$char('>')) {
                          if (parserInput.$char('=')) {
                              op = ">=";
                          } else {
                              op = '>';
                          }
                      } else
                      if (parserInput.$char('<')) {
                          if (parserInput.$char('=')) {
                              op = "<=";
                          } else {
                              op = '<';
                          }
                      } else
                      if (parserInput.$char('=')) {
                          if (parserInput.$char('>')) {
                              op = "=>";
                          } else if (parserInput.$char('<')) {
                              op = '=<';
                          } else {
                              op = '=';
                          }
                      }
                      if (op) {
                          b = this.addition() || entities.keyword() || entities.quoted();
                          if (b) {
                              c = new(tree.Condition)(op, a, b, index, false);
                          } else {
                              error('expected expression');
                          }
                      } else {
                          c = new(tree.Condition)('=', a, new(tree.Keyword)('true'), index, false);
                      }
                      return c;
                  }
              },
  
              //
              // An operand is anything that can be part of an operation,
              // such as a Color, or a Variable
              //
              operand: function () {
                  var entities = this.entities, negate;
  
                  if (parserInput.peek(/^-[@\$\(]/)) {
                      negate = parserInput.$char('-');
                  }
  
                  var o = this.sub() || entities.dimension() ||
                          entities.color() || entities.variable() ||
                          entities.property() || entities.call() ||
                          entities.colorKeyword();
  
                  if (negate) {
                      o.parensInOp = true;
                      o = new(tree.Negative)(o);
                  }
  
                  return o;
              },
  
              //
              // Expressions either represent mathematical operations,
              // or white-space delimited Entities.
              //
              //     1px solid black
              //     @var * 2
              //
              expression: function () {
                  var entities = [], e, delim, index = parserInput.i;
  
                  do {
                      e = this.comment();
                      if (e) {
                          entities.push(e);
                          continue;
                      }
                      e = this.addition() || this.entity();
                      if (e) {
                          entities.push(e);
                          // operations do not allow keyword "/" dimension (e.g. small/20px) so we support that here
                          if (!parserInput.peek(/^\/[\/*]/)) {
                              delim = parserInput.$char('/');
                              if (delim) {
                                  entities.push(new(tree.Anonymous)(delim, index));
                              }
                          }
                      }
                  } while (e);
                  if (entities.length > 0) {
                      return new(tree.Expression)(entities);
                  }
              },
              property: function () {
                  var name = parserInput.$re(/^(\*?-?[_a-zA-Z0-9-]+)\s*:/);
                  if (name) {
                      return name[1];
                  }
              },
              ruleProperty: function () {
                  var name = [], index = [], s, k;
  
                  parserInput.save();
  
                  var simpleProperty = parserInput.$re(/^([_a-zA-Z0-9-]+)\s*:/);
                  if (simpleProperty) {
                      name = [new(tree.Keyword)(simpleProperty[1])];
                      parserInput.forget();
                      return name;
                  }
  
                  function match(re) {
                      var i = parserInput.i,
                          chunk = parserInput.$re(re);
                      if (chunk) {
                          index.push(i);
                          return name.push(chunk[1]);
                      }
                  }
  
                  match(/^(\*?)/);
                  while (true) {
                      if (!match(/^((?:[\w-]+)|(?:[@\$]\{[\w-]+\}))/)) {
                          break;
                      }
                  }
  
                  if ((name.length > 1) && match(/^((?:\+_|\+)?)\s*:/)) {
                      parserInput.forget();
  
                      // at last, we have the complete match now. move forward,
                      // convert name particles to tree objects and return:
                      if (name[0] === '') {
                          name.shift();
                          index.shift();
                      }
                      for (k = 0; k < name.length; k++) {
                          s = name[k];
                          name[k] = (s.charAt(0) !== '@' && s.charAt(0) !== '$') ?
                              new(tree.Keyword)(s) :
                              (s.charAt(0) === '@' ?
                                  new(tree.Variable)('@' + s.slice(2, -1), index[k], fileInfo) :
                                  new(tree.Property)('$' + s.slice(2, -1), index[k], fileInfo));
                      }
                      return name;
                  }
                  parserInput.restore();
              }
          }
      };
  };
  Parser.serializeVars = function(vars) {
      var s = '';
  
      for (var name in vars) {
          if (Object.hasOwnProperty.call(vars, name)) {
              var value = vars[name];
              s += ((name[0] === '@') ? '' : '@') + name + ': ' + value +
                  ((String(value).slice(-1) === ';') ? '' : ';');
          }
      }
  
      return s;
  };
  
  module.exports = Parser;
  
  },{"../functions/function-registry":26,"../less-error":36,"../tree":65,"../utils":86,"../visitors":90,"./parser-input":41}],43:[function(require,module,exports){
  /**
   * Plugin Manager
   */
  var PluginManager = function(less) {
      this.less = less;
      this.visitors = [];
      this.preProcessors = [];
      this.postProcessors = [];
      this.installedPlugins = [];
      this.fileManagers = [];
      this.iterator = -1;
      this.pluginCache = {};
      this.Loader = new less.PluginLoader(less);
  };
  
  var pm, PluginManagerFactory = function(less, newFactory) {
          if (newFactory || !pm) {
              pm = new PluginManager(less);
          }
          return pm;
      };
  
  /**
   * Adds all the plugins in the array
   * @param {Array} plugins
   */
  PluginManager.prototype.addPlugins = function(plugins) {
      if (plugins) {
          for (var i = 0; i < plugins.length; i++) {
              this.addPlugin(plugins[i]);
          }
      }
  };
  /**
   *
   * @param plugin
   * @param {String} filename
   */
  PluginManager.prototype.addPlugin = function(plugin, filename, functionRegistry) {
      this.installedPlugins.push(plugin);
      if (filename) {
          this.pluginCache[filename] = plugin;
      }
      if (plugin.install) {
          plugin.install(this.less, this, functionRegistry || this.less.functions.functionRegistry);
      }
  };
  /**
   *
   * @param filename
   */
  PluginManager.prototype.get = function(filename) {
      return this.pluginCache[filename];
  };
  
  /**
   * Adds a visitor. The visitor object has options on itself to determine
   * when it should run.
   * @param visitor
   */
  PluginManager.prototype.addVisitor = function(visitor) {
      this.visitors.push(visitor);
  };
  /**
   * Adds a pre processor object
   * @param {object} preProcessor
   * @param {number} priority - guidelines 1 = before import, 1000 = import, 2000 = after import
   */
  PluginManager.prototype.addPreProcessor = function(preProcessor, priority) {
      var indexToInsertAt;
      for (indexToInsertAt = 0; indexToInsertAt < this.preProcessors.length; indexToInsertAt++) {
          if (this.preProcessors[indexToInsertAt].priority >= priority) {
              break;
          }
      }
      this.preProcessors.splice(indexToInsertAt, 0, {preProcessor: preProcessor, priority: priority});
  };
  /**
   * Adds a post processor object
   * @param {object} postProcessor
   * @param {number} priority - guidelines 1 = before compression, 1000 = compression, 2000 = after compression
   */
  PluginManager.prototype.addPostProcessor = function(postProcessor, priority) {
      var indexToInsertAt;
      for (indexToInsertAt = 0; indexToInsertAt < this.postProcessors.length; indexToInsertAt++) {
          if (this.postProcessors[indexToInsertAt].priority >= priority) {
              break;
          }
      }
      this.postProcessors.splice(indexToInsertAt, 0, {postProcessor: postProcessor, priority: priority});
  };
  /**
   *
   * @param manager
   */
  PluginManager.prototype.addFileManager = function(manager) {
      this.fileManagers.push(manager);
  };
  /**
   *
   * @returns {Array}
   * @private
   */
  PluginManager.prototype.getPreProcessors = function() {
      var preProcessors = [];
      for (var i = 0; i < this.preProcessors.length; i++) {
          preProcessors.push(this.preProcessors[i].preProcessor);
      }
      return preProcessors;
  };
  /**
   *
   * @returns {Array}
   * @private
   */
  PluginManager.prototype.getPostProcessors = function() {
      var postProcessors = [];
      for (var i = 0; i < this.postProcessors.length; i++) {
          postProcessors.push(this.postProcessors[i].postProcessor);
      }
      return postProcessors;
  };
  /**
   *
   * @returns {Array}
   * @private
   */
  PluginManager.prototype.getVisitors = function() {
      return this.visitors;
  };
  
  PluginManager.prototype.visitor = function() {
      var self = this;
      return {
          first: function() {
              self.iterator = -1;
              return self.visitors[self.iterator];
          },
          get: function() {
              self.iterator += 1;
              return self.visitors[self.iterator];
          }
      };
  };
  /**
   *
   * @returns {Array}
   * @private
   */
  PluginManager.prototype.getFileManagers = function() {
      return this.fileManagers;
  };
  
  // 
  module.exports = PluginManagerFactory;
  
  },{}],44:[function(require,module,exports){
  var PromiseConstructor,
      utils = require('./utils');
  
  module.exports = function(environment, ParseTree, ImportManager) {
      var render = function (input, options, callback) {
          if (typeof options === 'function') {
              callback = options;
              options = utils.defaults(this.options, {});
          }
          else {
              options = utils.defaults(this.options, options || {});
          }
  
          if (!callback) {
              if (!PromiseConstructor) {
                  PromiseConstructor = typeof Promise === 'undefined' ? require('promise') : Promise;
              }
              var self = this;
              return new PromiseConstructor(function (resolve, reject) {
                  render.call(self, input, options, function(err, output) {
                      if (err) {
                          reject(err);
                      } else {
                          resolve(output);
                      }
                  });
              });
          } else {
              this.parse(input, options, function(err, root, imports, options) {
                  if (err) { return callback(err); }
  
                  var result;
                  try {
                      var parseTree = new ParseTree(root, imports);
                      result = parseTree.toCSS(options);
                  }
                  catch (err) { return callback(err); }
  
                  callback(null, result);
              });
          }
      };
  
      return render;
  };
  
  },{"./utils":86,"promise":undefined}],45:[function(require,module,exports){
  module.exports = function (SourceMapOutput, environment) {
  
      var SourceMapBuilder = function (options) {
          this.options = options;
      };
  
      SourceMapBuilder.prototype.toCSS = function(rootNode, options, imports) {
          var sourceMapOutput = new SourceMapOutput(
              {
                  contentsIgnoredCharsMap: imports.contentsIgnoredChars,
                  rootNode: rootNode,
                  contentsMap: imports.contents,
                  sourceMapFilename: this.options.sourceMapFilename,
                  sourceMapURL: this.options.sourceMapURL,
                  outputFilename: this.options.sourceMapOutputFilename,
                  sourceMapBasepath: this.options.sourceMapBasepath,
                  sourceMapRootpath: this.options.sourceMapRootpath,
                  outputSourceFiles: this.options.outputSourceFiles,
                  sourceMapGenerator: this.options.sourceMapGenerator,
                  sourceMapFileInline: this.options.sourceMapFileInline
              });
  
          var css = sourceMapOutput.toCSS(options);
          this.sourceMap = sourceMapOutput.sourceMap;
          this.sourceMapURL = sourceMapOutput.sourceMapURL;
          if (this.options.sourceMapInputFilename) {
              this.sourceMapInputFilename = sourceMapOutput.normalizeFilename(this.options.sourceMapInputFilename);
          }
          if (this.options.sourceMapBasepath !== undefined && this.sourceMapURL !== undefined) {
              this.sourceMapURL = sourceMapOutput.removeBasepath(this.sourceMapURL);
          }
          return css + this.getCSSAppendage();
      };
  
      SourceMapBuilder.prototype.getCSSAppendage = function() {
  
          var sourceMapURL = this.sourceMapURL;
          if (this.options.sourceMapFileInline) {
              if (this.sourceMap === undefined) {
                  return "";
              }
              sourceMapURL = "data:application/json;base64," + environment.encodeBase64(this.sourceMap);
          }
  
          if (sourceMapURL) {
              return "/*# sourceMappingURL=" + sourceMapURL + " */";
          }
          return "";
      };
  
      SourceMapBuilder.prototype.getExternalSourceMap = function() {
          return this.sourceMap;
      };
      SourceMapBuilder.prototype.setExternalSourceMap = function(sourceMap) {
          this.sourceMap = sourceMap;
      };
  
      SourceMapBuilder.prototype.isInline = function() {
          return this.options.sourceMapFileInline;
      };
      SourceMapBuilder.prototype.getSourceMapURL = function() {
          return this.sourceMapURL;
      };
      SourceMapBuilder.prototype.getOutputFilename = function() {
          return this.options.sourceMapOutputFilename;
      };
      SourceMapBuilder.prototype.getInputFilename = function() {
          return this.sourceMapInputFilename;
      };
  
      return SourceMapBuilder;
  };
  
  },{}],46:[function(require,module,exports){
  module.exports = function (environment) {
  
      var SourceMapOutput = function (options) {
          this._css = [];
          this._rootNode = options.rootNode;
          this._contentsMap = options.contentsMap;
          this._contentsIgnoredCharsMap = options.contentsIgnoredCharsMap;
          if (options.sourceMapFilename) {
              this._sourceMapFilename = options.sourceMapFilename.replace(/\\/g, '/');
          }
          this._outputFilename = options.outputFilename;
          this.sourceMapURL = options.sourceMapURL;
          if (options.sourceMapBasepath) {
              this._sourceMapBasepath = options.sourceMapBasepath.replace(/\\/g, '/');
          }
          if (options.sourceMapRootpath) {
              this._sourceMapRootpath = options.sourceMapRootpath.replace(/\\/g, '/');
              if (this._sourceMapRootpath.charAt(this._sourceMapRootpath.length - 1) !== '/') {
                  this._sourceMapRootpath += '/';
              }
          } else {
              this._sourceMapRootpath = "";
          }
          this._outputSourceFiles = options.outputSourceFiles;
          this._sourceMapGeneratorConstructor = environment.getSourceMapGenerator();
  
          this._lineNumber = 0;
          this._column = 0;
      };
  
      SourceMapOutput.prototype.removeBasepath = function(path) {
          if (this._sourceMapBasepath && path.indexOf(this._sourceMapBasepath) === 0) {
              path = path.substring(this._sourceMapBasepath.length);
              if (path.charAt(0) === '\\' || path.charAt(0) === '/') {
                  path = path.substring(1);
              }
          }
  
          return path;
      };
  
      SourceMapOutput.prototype.normalizeFilename = function(filename) {
          filename = filename.replace(/\\/g, '/');
          filename = this.removeBasepath(filename);
          return (this._sourceMapRootpath || "") + filename;
      };
  
      SourceMapOutput.prototype.add = function(chunk, fileInfo, index, mapLines) {
  
          // ignore adding empty strings
          if (!chunk) {
              return;
          }
  
          var lines,
              sourceLines,
              columns,
              sourceColumns,
              i;
  
          if (fileInfo) {
              var inputSource = this._contentsMap[fileInfo.filename];
  
              // remove vars/banner added to the top of the file
              if (this._contentsIgnoredCharsMap[fileInfo.filename]) {
                  // adjust the index
                  index -= this._contentsIgnoredCharsMap[fileInfo.filename];
                  if (index < 0) { index = 0; }
                  // adjust the source
                  inputSource = inputSource.slice(this._contentsIgnoredCharsMap[fileInfo.filename]);
              }
              inputSource = inputSource.substring(0, index);
              sourceLines = inputSource.split("\n");
              sourceColumns = sourceLines[sourceLines.length - 1];
          }
  
          lines = chunk.split("\n");
          columns = lines[lines.length - 1];
  
          if (fileInfo) {
              if (!mapLines) {
                  this._sourceMapGenerator.addMapping({ generated: { line: this._lineNumber + 1, column: this._column},
                      original: { line: sourceLines.length, column: sourceColumns.length},
                      source: this.normalizeFilename(fileInfo.filename)});
              } else {
                  for (i = 0; i < lines.length; i++) {
                      this._sourceMapGenerator.addMapping({ generated: { line: this._lineNumber + i + 1, column: i === 0 ? this._column : 0},
                          original: { line: sourceLines.length + i, column: i === 0 ? sourceColumns.length : 0},
                          source: this.normalizeFilename(fileInfo.filename)});
                  }
              }
          }
  
          if (lines.length === 1) {
              this._column += columns.length;
          } else {
              this._lineNumber += lines.length - 1;
              this._column = columns.length;
          }
  
          this._css.push(chunk);
      };
  
      SourceMapOutput.prototype.isEmpty = function() {
          return this._css.length === 0;
      };
  
      SourceMapOutput.prototype.toCSS = function(context) {
          this._sourceMapGenerator = new this._sourceMapGeneratorConstructor({ file: this._outputFilename, sourceRoot: null });
  
          if (this._outputSourceFiles) {
              for (var filename in this._contentsMap) {
                  if (this._contentsMap.hasOwnProperty(filename)) {
                      var source = this._contentsMap[filename];
                      if (this._contentsIgnoredCharsMap[filename]) {
                          source = source.slice(this._contentsIgnoredCharsMap[filename]);
                      }
                      this._sourceMapGenerator.setSourceContent(this.normalizeFilename(filename), source);
                  }
              }
          }
  
          this._rootNode.genCSS(context, this);
  
          if (this._css.length > 0) {
              var sourceMapURL,
                  sourceMapContent = JSON.stringify(this._sourceMapGenerator.toJSON());
  
              if (this.sourceMapURL) {
                  sourceMapURL = this.sourceMapURL;
              } else if (this._sourceMapFilename) {
                  sourceMapURL = this._sourceMapFilename;
              }
              this.sourceMapURL = sourceMapURL;
  
              this.sourceMap = sourceMapContent;
          }
  
          return this._css.join('');
      };
  
      return SourceMapOutput;
  };
  
  },{}],47:[function(require,module,exports){
  var contexts = require("./contexts"),
      visitor = require("./visitors"),
      tree = require("./tree");
  
  module.exports = function(root, options) {
      options = options || {};
      var evaldRoot,
          variables = options.variables,
          evalEnv = new contexts.Eval(options);
  
      //
      // Allows setting variables with a hash, so:
      //
      //   `{ color: new tree.Color('#f01') }` will become:
      //
      //   new tree.Declaration('@color',
      //     new tree.Value([
      //       new tree.Expression([
      //         new tree.Color('#f01')
      //       ])
      //     ])
      //   )
      //
      if (typeof variables === 'object' && !Array.isArray(variables)) {
          variables = Object.keys(variables).map(function (k) {
              var value = variables[k];
  
              if (!(value instanceof tree.Value)) {
                  if (!(value instanceof tree.Expression)) {
                      value = new tree.Expression([value]);
                  }
                  value = new tree.Value([value]);
              }
              return new tree.Declaration('@' + k, value, false, null, 0);
          });
          evalEnv.frames = [new tree.Ruleset(null, variables)];
      }
  
      var visitors = [
              new visitor.JoinSelectorVisitor(),
              new visitor.MarkVisibleSelectorsVisitor(true),
              new visitor.ExtendVisitor(),
              new visitor.ToCSSVisitor({compress: Boolean(options.compress)})
          ], v, visitorIterator;
  
      // first() / get() allows visitors to be added while visiting
      if (options.pluginManager) {
          visitorIterator = options.pluginManager.visitor();
          visitorIterator.first();
          while ((v = visitorIterator.get())) {
              if (v.isPreEvalVisitor) {
                  v.run(root);
              }
          }
      }
  
      evaldRoot = root.eval(evalEnv);
  
      for (var i = 0; i < visitors.length; i++) {
          visitors[i].run(evaldRoot);
      }
  
      if (options.pluginManager) {
          visitorIterator.first();
          while ((v = visitorIterator.get())) {
              if (!v.isPreEvalVisitor) {
                  v.run(evaldRoot);
              }
          }
      }
  
      return evaldRoot;
  };
  
  },{"./contexts":12,"./tree":65,"./visitors":90}],48:[function(require,module,exports){
  var Node = require("./node");
  
  var Anonymous = function (value, index, currentFileInfo, mapLines, rulesetLike, visibilityInfo) {
      this.value = value;
      this._index = index;
      this._fileInfo = currentFileInfo;
      this.mapLines = mapLines;
      this.rulesetLike = (typeof rulesetLike === 'undefined') ? false : rulesetLike;
      this.allowRoot = true;
      this.copyVisibilityInfo(visibilityInfo);
  };
  Anonymous.prototype = new Node();
  Anonymous.prototype.type = "Anonymous";
  Anonymous.prototype.eval = function () {
      return new Anonymous(this.value, this._index, this._fileInfo, this.mapLines, this.rulesetLike, this.visibilityInfo());
  };
  Anonymous.prototype.compare = function (other) {
      return other.toCSS && this.toCSS() === other.toCSS() ? 0 : undefined;
  };
  Anonymous.prototype.isRulesetLike = function() {
      return this.rulesetLike;
  };
  Anonymous.prototype.genCSS = function (context, output) {
      this.nodeVisible = Boolean(this.value);
      if (this.nodeVisible) {
          output.add(this.value, this._fileInfo, this._index, this.mapLines);
      }
  };
  module.exports = Anonymous;
  
  },{"./node":73}],49:[function(require,module,exports){
  var Node = require("./node");
  
  var Assignment = function (key, val) {
      this.key = key;
      this.value = val;
  };
  
  Assignment.prototype = new Node();
  Assignment.prototype.type = "Assignment";
  Assignment.prototype.accept = function (visitor) {
      this.value = visitor.visit(this.value);
  };
  Assignment.prototype.eval = function (context) {
      if (this.value.eval) {
          return new Assignment(this.key, this.value.eval(context));
      }
      return this;
  };
  Assignment.prototype.genCSS = function (context, output) {
      output.add(this.key + '=');
      if (this.value.genCSS) {
          this.value.genCSS(context, output);
      } else {
          output.add(this.value);
      }
  };
  module.exports = Assignment;
  
  },{"./node":73}],50:[function(require,module,exports){
  var Node = require("./node"),
      Selector = require("./selector"),
      Ruleset = require("./ruleset"),
      Anonymous = require('./anonymous');
  
  var AtRule = function (name, value, rules, index, currentFileInfo, debugInfo, isRooted, visibilityInfo) {
      var i;
  
      this.name  = name;
      this.value = (value instanceof Node) ? value : (value ? new Anonymous(value) : value);
      if (rules) {
          if (Array.isArray(rules)) {
              this.rules = rules;
          } else {
              this.rules = [rules];
              this.rules[0].selectors = (new Selector([], null, null, index, currentFileInfo)).createEmptySelectors();
          }
          for (i = 0; i < this.rules.length; i++) {
              this.rules[i].allowImports = true;
          }
          this.setParent(this.rules, this);
      }
      this._index = index;
      this._fileInfo = currentFileInfo;
      this.debugInfo = debugInfo;
      this.isRooted = isRooted || false;
      this.copyVisibilityInfo(visibilityInfo);
      this.allowRoot = true;
  };
  
  AtRule.prototype = new Node();
  AtRule.prototype.type = "AtRule";
  AtRule.prototype.accept = function (visitor) {
      var value = this.value, rules = this.rules;
      if (rules) {
          this.rules = visitor.visitArray(rules);
      }
      if (value) {
          this.value = visitor.visit(value);
      }
  };
  AtRule.prototype.isRulesetLike = function() {
      return this.rules || !this.isCharset();
  };
  AtRule.prototype.isCharset = function() {
      return "@charset" === this.name;
  };
  AtRule.prototype.genCSS = function (context, output) {
      var value = this.value, rules = this.rules;
      output.add(this.name, this.fileInfo(), this.getIndex());
      if (value) {
          output.add(' ');
          value.genCSS(context, output);
      }
      if (rules) {
          this.outputRuleset(context, output, rules);
      } else {
          output.add(';');
      }
  };
  AtRule.prototype.eval = function (context) {
      var mediaPathBackup, mediaBlocksBackup, value = this.value, rules = this.rules;
  
      // media stored inside other atrule should not bubble over it
      // backpup media bubbling information
      mediaPathBackup = context.mediaPath;
      mediaBlocksBackup = context.mediaBlocks;
      // deleted media bubbling information
      context.mediaPath = [];
      context.mediaBlocks = [];
  
      if (value) {
          value = value.eval(context);
      }
      if (rules) {
          // assuming that there is only one rule at this point - that is how parser constructs the rule
          rules = [rules[0].eval(context)];
          rules[0].root = true;
      }
      // restore media bubbling information
      context.mediaPath = mediaPathBackup;
      context.mediaBlocks = mediaBlocksBackup;
  
      return new AtRule(this.name, value, rules,
          this.getIndex(), this.fileInfo(), this.debugInfo, this.isRooted, this.visibilityInfo());
  };
  AtRule.prototype.variable = function (name) {
      if (this.rules) {
          // assuming that there is only one rule at this point - that is how parser constructs the rule
          return Ruleset.prototype.variable.call(this.rules[0], name);
      }
  };
  AtRule.prototype.find = function () {
      if (this.rules) {
          // assuming that there is only one rule at this point - that is how parser constructs the rule
          return Ruleset.prototype.find.apply(this.rules[0], arguments);
      }
  };
  AtRule.prototype.rulesets = function () {
      if (this.rules) {
          // assuming that there is only one rule at this point - that is how parser constructs the rule
          return Ruleset.prototype.rulesets.apply(this.rules[0]);
      }
  };
  AtRule.prototype.outputRuleset = function (context, output, rules) {
      var ruleCnt = rules.length, i;
      context.tabLevel = (context.tabLevel | 0) + 1;
  
      // Compressed
      if (context.compress) {
          output.add('{');
          for (i = 0; i < ruleCnt; i++) {
              rules[i].genCSS(context, output);
          }
          output.add('}');
          context.tabLevel--;
          return;
      }
  
      // Non-compressed
      var tabSetStr = '\n' + Array(context.tabLevel).join("  "), tabRuleStr = tabSetStr + "  ";
      if (!ruleCnt) {
          output.add(" {" + tabSetStr + '}');
      } else {
          output.add(" {" + tabRuleStr);
          rules[0].genCSS(context, output);
          for (i = 1; i < ruleCnt; i++) {
              output.add(tabRuleStr);
              rules[i].genCSS(context, output);
          }
          output.add(tabSetStr + '}');
      }
  
      context.tabLevel--;
  };
  module.exports = AtRule;
  
  },{"./anonymous":48,"./node":73,"./ruleset":78,"./selector":79}],51:[function(require,module,exports){
  var Node = require("./node");
  
  var Attribute = function (key, op, value) {
      this.key = key;
      this.op = op;
      this.value = value;
  };
  Attribute.prototype = new Node();
  Attribute.prototype.type = "Attribute";
  Attribute.prototype.eval = function (context) {
      return new Attribute(this.key.eval ? this.key.eval(context) : this.key,
          this.op, (this.value && this.value.eval) ? this.value.eval(context) : this.value);
  };
  Attribute.prototype.genCSS = function (context, output) {
      output.add(this.toCSS(context));
  };
  Attribute.prototype.toCSS = function (context) {
      var value = this.key.toCSS ? this.key.toCSS(context) : this.key;
  
      if (this.op) {
          value += this.op;
          value += (this.value.toCSS ? this.value.toCSS(context) : this.value);
      }
  
      return '[' + value + ']';
  };
  module.exports = Attribute;
  
  },{"./node":73}],52:[function(require,module,exports){
  var Node = require("./node"),
      Anonymous = require("./anonymous"),
      FunctionCaller = require("../functions/function-caller");
  //
  // A function call node.
  //
  var Call = function (name, args, index, currentFileInfo) {
      this.name = name;
      this.args = args;
      this.mathOn = name === 'calc' ? false : true;
      this._index = index;
      this._fileInfo = currentFileInfo;
  };
  Call.prototype = new Node();
  Call.prototype.type = "Call";
  Call.prototype.accept = function (visitor) {
      if (this.args) {
          this.args = visitor.visitArray(this.args);
      }
  };
  //
  // When evaluating a function call,
  // we either find the function in the functionRegistry,
  // in which case we call it, passing the  evaluated arguments,
  // if this returns null or we cannot find the function, we
  // simply print it out as it appeared originally [2].
  //
  // The reason why we evaluate the arguments, is in the case where
  // we try to pass a variable to a function, like: `saturate(@color)`.
  // The function should receive the value, not the variable.
  //
  Call.prototype.eval = function (context) {
  
      /**
       * Turn off math for calc(), and switch back on for evaluating nested functions
       */
      var currentMathContext = context.mathOn;
      context.mathOn = this.mathOn;
      var args = this.args.map(function (a) { return a.eval(context); });
      context.mathOn = currentMathContext;
  
      var result, funcCaller = new FunctionCaller(this.name, context, this.getIndex(), this.fileInfo());
      
      if (funcCaller.isValid()) {
          try {
              result = funcCaller.call(args);
          } catch (e) {
              throw { 
                  type: e.type || "Runtime",
                  message: "error evaluating function `" + this.name + "`" +
                           (e.message ? ': ' + e.message : ''),
                  index: this.getIndex(), 
                  filename: this.fileInfo().filename,
                  line: e.lineNumber,
                  column: e.columnNumber
              };
          }
  
          if (result !== null && result !== undefined) {
              // Results that that are not nodes are cast as Anonymous nodes
              // Falsy values or booleans are returned as empty nodes
              if (!(result instanceof Node)) {
                  if (!result || result === true) {
                      result = new Anonymous(null); 
                  }
                  else {
                      result = new Anonymous(result.toString()); 
                  }
                  
              }
              result._index = this._index;
              result._fileInfo = this._fileInfo;
              return result;
          }
  
      }
  
      return new Call(this.name, args, this.getIndex(), this.fileInfo());
  };
  Call.prototype.genCSS = function (context, output) {
      output.add(this.name + "(", this.fileInfo(), this.getIndex());
  
      for (var i = 0; i < this.args.length; i++) {
          this.args[i].genCSS(context, output);
          if (i + 1 < this.args.length) {
              output.add(", ");
          }
      }
  
      output.add(")");
  };
  module.exports = Call;
  
  },{"../functions/function-caller":25,"./anonymous":48,"./node":73}],53:[function(require,module,exports){
  var Node = require("./node"),
      colors = require("../data/colors");
  
  //
  // RGB Colors - #ff0014, #eee
  //
  var Color = function (rgb, a, originalForm) {
      //
      // The end goal here, is to parse the arguments
      // into an integer triplet, such as `128, 255, 0`
      //
      // This facilitates operations and conversions.
      //
      if (Array.isArray(rgb)) {
          this.rgb = rgb;
      } else if (rgb.length == 6) {
          this.rgb = rgb.match(/.{2}/g).map(function (c) {
              return parseInt(c, 16);
          });
      } else {
          this.rgb = rgb.split('').map(function (c) {
              return parseInt(c + c, 16);
          });
      }
      this.alpha = typeof a === 'number' ? a : 1;
      if (typeof originalForm !== 'undefined') {
          this.value = originalForm;
      }
  };
  
  Color.prototype = new Node();
  Color.prototype.type = "Color";
  
  function clamp(v, max) {
      return Math.min(Math.max(v, 0), max);
  }
  
  function toHex(v) {
      return '#' + v.map(function (c) {
          c = clamp(Math.round(c), 255);
          return (c < 16 ? '0' : '') + c.toString(16);
      }).join('');
  }
  
  Color.prototype.luma = function () {
      var r = this.rgb[0] / 255,
          g = this.rgb[1] / 255,
          b = this.rgb[2] / 255;
  
      r = (r <= 0.03928) ? r / 12.92 : Math.pow(((r + 0.055) / 1.055), 2.4);
      g = (g <= 0.03928) ? g / 12.92 : Math.pow(((g + 0.055) / 1.055), 2.4);
      b = (b <= 0.03928) ? b / 12.92 : Math.pow(((b + 0.055) / 1.055), 2.4);
  
      return 0.2126 * r + 0.7152 * g + 0.0722 * b;
  };
  Color.prototype.genCSS = function (context, output) {
      output.add(this.toCSS(context));
  };
  Color.prototype.toCSS = function (context, doNotCompress) {
      var compress = context && context.compress && !doNotCompress, color, alpha;
  
      // `value` is set if this color was originally
      // converted from a named color string so we need
      // to respect this and try to output named color too.
      if (this.value) {
          return this.value;
      }
  
      // If we have some transparency, the only way to represent it
      // is via `rgba`. Otherwise, we use the hex representation,
      // which has better compatibility with older browsers.
      // Values are capped between `0` and `255`, rounded and zero-padded.
      alpha = this.fround(context, this.alpha);
      if (alpha < 1) {
          return "rgba(" + this.rgb.map(function (c) {
              return clamp(Math.round(c), 255);
          }).concat(clamp(alpha, 1))
              .join(',' + (compress ? '' : ' ')) + ")";
      }
  
      color = this.toRGB();
  
      if (compress) {
          var splitcolor = color.split('');
  
          // Convert color to short format
          if (splitcolor[1] === splitcolor[2] && splitcolor[3] === splitcolor[4] && splitcolor[5] === splitcolor[6]) {
              color = '#' + splitcolor[1] + splitcolor[3] + splitcolor[5];
          }
      }
  
      return color;
  };
  
  //
  // Operations have to be done per-channel, if not,
  // channels will spill onto each other. Once we have
  // our result, in the form of an integer triplet,
  // we create a new Color node to hold the result.
  //
  Color.prototype.operate = function (context, op, other) {
      var rgb = new Array(3);
      var alpha = this.alpha * (1 - other.alpha) + other.alpha;
      for (var c = 0; c < 3; c++) {
          rgb[c] = this._operate(context, op, this.rgb[c], other.rgb[c]);
      }
      return new Color(rgb, alpha);
  };
  Color.prototype.toRGB = function () {
      return toHex(this.rgb);
  };
  Color.prototype.toHSL = function () {
      var r = this.rgb[0] / 255,
          g = this.rgb[1] / 255,
          b = this.rgb[2] / 255,
          a = this.alpha;
  
      var max = Math.max(r, g, b), min = Math.min(r, g, b);
      var h, s, l = (max + min) / 2, d = max - min;
  
      if (max === min) {
          h = s = 0;
      } else {
          s = l > 0.5 ? d / (2 - max - min) : d / (max + min);
  
          switch (max) {
              case r: h = (g - b) / d + (g < b ? 6 : 0); break;
              case g: h = (b - r) / d + 2;               break;
              case b: h = (r - g) / d + 4;               break;
          }
          h /= 6;
      }
      return { h: h * 360, s: s, l: l, a: a };
  };
  // Adapted from http://mjijackson.com/2008/02/rgb-to-hsl-and-rgb-to-hsv-color-model-conversion-algorithms-in-javascript
  Color.prototype.toHSV = function () {
      var r = this.rgb[0] / 255,
          g = this.rgb[1] / 255,
          b = this.rgb[2] / 255,
          a = this.alpha;
  
      var max = Math.max(r, g, b), min = Math.min(r, g, b);
      var h, s, v = max;
  
      var d = max - min;
      if (max === 0) {
          s = 0;
      } else {
          s = d / max;
      }
  
      if (max === min) {
          h = 0;
      } else {
          switch (max) {
              case r: h = (g - b) / d + (g < b ? 6 : 0); break;
              case g: h = (b - r) / d + 2; break;
              case b: h = (r - g) / d + 4; break;
          }
          h /= 6;
      }
      return { h: h * 360, s: s, v: v, a: a };
  };
  Color.prototype.toARGB = function () {
      return toHex([this.alpha * 255].concat(this.rgb));
  };
  Color.prototype.compare = function (x) {
      return (x.rgb &&
          x.rgb[0] === this.rgb[0] &&
          x.rgb[1] === this.rgb[1] &&
          x.rgb[2] === this.rgb[2] &&
          x.alpha  === this.alpha) ? 0 : undefined;
  };
  
  Color.fromKeyword = function(keyword) {
      var c, key = keyword.toLowerCase();
      if (colors.hasOwnProperty(key)) {
          c = new Color(colors[key].slice(1));
      }
      else if (key === "transparent") {
          c = new Color([0, 0, 0], 0);
      }
  
      if (c) {
          c.value = keyword;
          return c;
      }
  };
  module.exports = Color;
  
  },{"../data/colors":13,"./node":73}],54:[function(require,module,exports){
  var Node = require("./node");
  
  var Combinator = function (value) {
      if (value === ' ') {
          this.value = ' ';
          this.emptyOrWhitespace = true;
      } else {
          this.value = value ? value.trim() : "";
          this.emptyOrWhitespace = this.value === "";
      }
  };
  Combinator.prototype = new Node();
  Combinator.prototype.type = "Combinator";
  var _noSpaceCombinators = {
      '': true,
      ' ': true,
      '|': true
  };
  Combinator.prototype.genCSS = function (context, output) {
      var spaceOrEmpty = (context.compress || _noSpaceCombinators[this.value]) ? '' : ' ';
      output.add(spaceOrEmpty + this.value + spaceOrEmpty);
  };
  module.exports = Combinator;
  
  },{"./node":73}],55:[function(require,module,exports){
  var Node = require("./node"),
      getDebugInfo = require("./debug-info");
  
  var Comment = function (value, isLineComment, index, currentFileInfo) {
      this.value = value;
      this.isLineComment = isLineComment;
      this._index = index;
      this._fileInfo = currentFileInfo;
      this.allowRoot = true;
  };
  Comment.prototype = new Node();
  Comment.prototype.type = "Comment";
  Comment.prototype.genCSS = function (context, output) {
      if (this.debugInfo) {
          output.add(getDebugInfo(context, this), this.fileInfo(), this.getIndex());
      }
      output.add(this.value);
  };
  Comment.prototype.isSilent = function(context) {
      var isCompressed = context.compress && this.value[2] !== "!";
      return this.isLineComment || isCompressed;
  };
  module.exports = Comment;
  
  },{"./debug-info":57,"./node":73}],56:[function(require,module,exports){
  var Node = require("./node");
  
  var Condition = function (op, l, r, i, negate) {
      this.op = op.trim();
      this.lvalue = l;
      this.rvalue = r;
      this._index = i;
      this.negate = negate;
  };
  Condition.prototype = new Node();
  Condition.prototype.type = "Condition";
  Condition.prototype.accept = function (visitor) {
      this.lvalue = visitor.visit(this.lvalue);
      this.rvalue = visitor.visit(this.rvalue);
  };
  Condition.prototype.eval = function (context) {
      var result = (function (op, a, b) {
          switch (op) {
              case 'and': return a && b;
              case 'or':  return a || b;
              default:
                  switch (Node.compare(a, b)) {
                      case -1:
                          return op === '<' || op === '=<' || op === '<=';
                      case 0:
                          return op === '=' || op === '>=' || op === '=<' || op === '<=';
                      case 1:
                          return op === '>' || op === '>=';
                      default:
                          return false;
                  }
          }
      })(this.op, this.lvalue.eval(context), this.rvalue.eval(context));
  
      return this.negate ? !result : result;
  };
  module.exports = Condition;
  
  },{"./node":73}],57:[function(require,module,exports){
  var debugInfo = function(context, ctx, lineSeparator) {
      var result = "";
      if (context.dumpLineNumbers && !context.compress) {
          switch (context.dumpLineNumbers) {
              case 'comments':
                  result = debugInfo.asComment(ctx);
                  break;
              case 'mediaquery':
                  result = debugInfo.asMediaQuery(ctx);
                  break;
              case 'all':
                  result = debugInfo.asComment(ctx) + (lineSeparator || "") + debugInfo.asMediaQuery(ctx);
                  break;
          }
      }
      return result;
  };
  
  debugInfo.asComment = function(ctx) {
      return '/* line ' + ctx.debugInfo.lineNumber + ', ' + ctx.debugInfo.fileName + ' */\n';
  };
  
  debugInfo.asMediaQuery = function(ctx) {
      var filenameWithProtocol = ctx.debugInfo.fileName;
      if (!/^[a-z]+:\/\//i.test(filenameWithProtocol)) {
          filenameWithProtocol = 'file://' + filenameWithProtocol;
      }
      return '@media -sass-debug-info{filename{font-family:' +
          filenameWithProtocol.replace(/([.:\/\\])/g, function (a) {
              if (a == '\\') {
                  a = '\/';
              }
              return '\\' + a;
          }) +
          '}line{font-family:\\00003' + ctx.debugInfo.lineNumber + '}}\n';
  };
  
  module.exports = debugInfo;
  
  },{}],58:[function(require,module,exports){
  var Node = require("./node"),
      Value = require("./value"),
      Keyword = require("./keyword"),
      Anonymous = require("./anonymous");
  
  var Declaration = function (name, value, important, merge, index, currentFileInfo, inline, variable) {
      this.name = name;
      this.value = (value instanceof Node) ? value : new Value([value ? new Anonymous(value) : null]);
      this.important = important ? ' ' + important.trim() : '';
      this.merge = merge;
      this._index = index;
      this._fileInfo = currentFileInfo;
      this.inline = inline || false;
      this.variable = (variable !== undefined) ? variable
          : (name.charAt && (name.charAt(0) === '@'));
      this.allowRoot = true;
      this.setParent(this.value, this);
  };
  
  function evalName(context, name) {
      var value = "", i, n = name.length,
          output = {add: function (s) {value += s;}};
      for (i = 0; i < n; i++) {
          name[i].eval(context).genCSS(context, output);
      }
      return value;
  }
  
  Declaration.prototype = new Node();
  Declaration.prototype.type = "Declaration";
  Declaration.prototype.genCSS = function (context, output) {
      output.add(this.name + (context.compress ? ':' : ': '), this.fileInfo(), this.getIndex());
      try {
          this.value.genCSS(context, output);
      }
      catch (e) {
          e.index = this._index;
          e.filename = this._fileInfo.filename;
          throw e;
      }
      output.add(this.important + ((this.inline || (context.lastRule && context.compress)) ? "" : ";"), this._fileInfo, this._index);
  };
  Declaration.prototype.eval = function (context) {
      var strictMathBypass = false, name = this.name, evaldValue, variable = this.variable;
      if (typeof name !== "string") {
          // expand 'primitive' name directly to get
          // things faster (~10% for benchmark.less):
          name = (name.length === 1) && (name[0] instanceof Keyword) ?
                  name[0].value : evalName(context, name);
          variable = false; // never treat expanded interpolation as new variable name
      }
      if (name === "font" && !context.strictMath) {
          strictMathBypass = true;
          context.strictMath = true;
      }
      try {
          context.importantScope.push({});
          evaldValue = this.value.eval(context);
  
          if (!this.variable && evaldValue.type === "DetachedRuleset") {
              throw { message: "Rulesets cannot be evaluated on a property.",
                  index: this.getIndex(), filename: this.fileInfo().filename };
          }
          var important = this.important,
              importantResult = context.importantScope.pop();
          if (!important && importantResult.important) {
              important = importantResult.important;
          }
  
          return new Declaration(name,
                            evaldValue,
                            important,
                            this.merge,
                            this.getIndex(), this.fileInfo(), this.inline,
                                variable);
      }
      catch (e) {
          if (typeof e.index !== 'number') {
              e.index = this.getIndex();
              e.filename = this.fileInfo().filename;
          }
          throw e;
      }
      finally {
          if (strictMathBypass) {
              context.strictMath = false;
          }
      }
  };
  Declaration.prototype.makeImportant = function () {
      return new Declaration(this.name,
                            this.value,
                            "!important",
                            this.merge,
                            this.getIndex(), this.fileInfo(), this.inline);
  };
  
  module.exports = Declaration;
  },{"./anonymous":48,"./keyword":68,"./node":73,"./value":83}],59:[function(require,module,exports){
  var Node = require("./node"),
      contexts = require("../contexts"),
      utils = require("../utils");
  
  var DetachedRuleset = function (ruleset, frames) {
      this.ruleset = ruleset;
      this.frames = frames;
      this.setParent(this.ruleset, this);
  };
  DetachedRuleset.prototype = new Node();
  DetachedRuleset.prototype.type = "DetachedRuleset";
  DetachedRuleset.prototype.evalFirst = true;
  DetachedRuleset.prototype.accept = function (visitor) {
      this.ruleset = visitor.visit(this.ruleset);
  };
  DetachedRuleset.prototype.eval = function (context) {
      var frames = this.frames || utils.copyArray(context.frames);
      return new DetachedRuleset(this.ruleset, frames);
  };
  DetachedRuleset.prototype.callEval = function (context) {
      return this.ruleset.eval(this.frames ? new contexts.Eval(context, this.frames.concat(context.frames)) : context);
  };
  module.exports = DetachedRuleset;
  
  },{"../contexts":12,"../utils":86,"./node":73}],60:[function(require,module,exports){
  var Node = require("./node"),
      unitConversions = require("../data/unit-conversions"),
      Unit = require("./unit"),
      Color = require("./color");
  
  //
  // A number with a unit
  //
  var Dimension = function (value, unit) {
      this.value = parseFloat(value);
      if (isNaN(this.value)) {
          throw new Error("Dimension is not a number.");
      }
      this.unit = (unit && unit instanceof Unit) ? unit :
        new Unit(unit ? [unit] : undefined);
      this.setParent(this.unit, this);
  };
  
  Dimension.prototype = new Node();
  Dimension.prototype.type = "Dimension";
  Dimension.prototype.accept = function (visitor) {
      this.unit = visitor.visit(this.unit);
  };
  Dimension.prototype.eval = function (context) {
      return this;
  };
  Dimension.prototype.toColor = function () {
      return new Color([this.value, this.value, this.value]);
  };
  Dimension.prototype.genCSS = function (context, output) {
      if ((context && context.strictUnits) && !this.unit.isSingular()) {
          throw new Error("Multiple units in dimension. Correct the units or use the unit function. Bad unit: " + this.unit.toString());
      }
  
      var value = this.fround(context, this.value),
          strValue = String(value);
  
      if (value !== 0 && value < 0.000001 && value > -0.000001) {
          // would be output 1e-6 etc.
          strValue = value.toFixed(20).replace(/0+$/, "");
      }
  
      if (context && context.compress) {
          // Zero values doesn't need a unit
          if (value === 0 && this.unit.isLength()) {
              output.add(strValue);
              return;
          }
  
          // Float values doesn't need a leading zero
          if (value > 0 && value < 1) {
              strValue = (strValue).substr(1);
          }
      }
  
      output.add(strValue);
      this.unit.genCSS(context, output);
  };
  
  // In an operation between two Dimensions,
  // we default to the first Dimension's unit,
  // so `1px + 2` will yield `3px`.
  Dimension.prototype.operate = function (context, op, other) {
      /* jshint noempty:false */
      var value = this._operate(context, op, this.value, other.value),
          unit = this.unit.clone();
  
      if (op === '+' || op === '-') {
          if (unit.numerator.length === 0 && unit.denominator.length === 0) {
              unit = other.unit.clone();
              if (this.unit.backupUnit) {
                  unit.backupUnit = this.unit.backupUnit;
              }
          } else if (other.unit.numerator.length === 0 && unit.denominator.length === 0) {
              // do nothing
          } else {
              other = other.convertTo(this.unit.usedUnits());
  
              if (context.strictUnits && other.unit.toString() !== unit.toString()) {
                  throw new Error("Incompatible units. Change the units or use the unit function. Bad units: '" + unit.toString() +
                      "' and '" + other.unit.toString() + "'.");
              }
  
              value = this._operate(context, op, this.value, other.value);
          }
      } else if (op === '*') {
          unit.numerator = unit.numerator.concat(other.unit.numerator).sort();
          unit.denominator = unit.denominator.concat(other.unit.denominator).sort();
          unit.cancel();
      } else if (op === '/') {
          unit.numerator = unit.numerator.concat(other.unit.denominator).sort();
          unit.denominator = unit.denominator.concat(other.unit.numerator).sort();
          unit.cancel();
      }
      return new Dimension(value, unit);
  };
  Dimension.prototype.compare = function (other) {
      var a, b;
  
      if (!(other instanceof Dimension)) {
          return undefined;
      }
  
      if (this.unit.isEmpty() || other.unit.isEmpty()) {
          a = this;
          b = other;
      } else {
          a = this.unify();
          b = other.unify();
          if (a.unit.compare(b.unit) !== 0) {
              return undefined;
          }
      }
  
      return Node.numericCompare(a.value, b.value);
  };
  Dimension.prototype.unify = function () {
      return this.convertTo({ length: 'px', duration: 's', angle: 'rad' });
  };
  Dimension.prototype.convertTo = function (conversions) {
      var value = this.value, unit = this.unit.clone(),
          i, groupName, group, targetUnit, derivedConversions = {}, applyUnit;
  
      if (typeof conversions === 'string') {
          for (i in unitConversions) {
              if (unitConversions[i].hasOwnProperty(conversions)) {
                  derivedConversions = {};
                  derivedConversions[i] = conversions;
              }
          }
          conversions = derivedConversions;
      }
      applyUnit = function (atomicUnit, denominator) {
          /* jshint loopfunc:true */
          if (group.hasOwnProperty(atomicUnit)) {
              if (denominator) {
                  value = value / (group[atomicUnit] / group[targetUnit]);
              } else {
                  value = value * (group[atomicUnit] / group[targetUnit]);
              }
  
              return targetUnit;
          }
  
          return atomicUnit;
      };
  
      for (groupName in conversions) {
          if (conversions.hasOwnProperty(groupName)) {
              targetUnit = conversions[groupName];
              group = unitConversions[groupName];
  
              unit.map(applyUnit);
          }
      }
  
      unit.cancel();
  
      return new Dimension(value, unit);
  };
  module.exports = Dimension;
  
  },{"../data/unit-conversions":15,"./color":53,"./node":73,"./unit":81}],61:[function(require,module,exports){
  var Node = require("./node"),
      Paren = require("./paren"),
      Combinator = require("./combinator");
  
  var Element = function (combinator, value, index, currentFileInfo, visibilityInfo) {
      this.combinator = combinator instanceof Combinator ?
                        combinator : new Combinator(combinator);
  
      if (typeof value === 'string') {
          this.value = value.trim();
      } else if (value) {
          this.value = value;
      } else {
          this.value = "";
      }
      this._index = index;
      this._fileInfo = currentFileInfo;
      this.copyVisibilityInfo(visibilityInfo);
      this.setParent(this.combinator, this);
  };
  Element.prototype = new Node();
  Element.prototype.type = "Element";
  Element.prototype.accept = function (visitor) {
      var value = this.value;
      this.combinator = visitor.visit(this.combinator);
      if (typeof value === "object") {
          this.value = visitor.visit(value);
      }
  };
  Element.prototype.eval = function (context) {
      return new Element(this.combinator,
                               this.value.eval ? this.value.eval(context) : this.value,
                               this.getIndex(),
                               this.fileInfo(), this.visibilityInfo());
  };
  Element.prototype.clone = function () {
      return new Element(this.combinator,
          this.value,
          this.getIndex(),
          this.fileInfo(), this.visibilityInfo());
  };
  Element.prototype.genCSS = function (context, output) {
      output.add(this.toCSS(context), this.fileInfo(), this.getIndex());
  };
  Element.prototype.toCSS = function (context) {
      context = context || {};
      var value = this.value, firstSelector = context.firstSelector;
      if (value instanceof Paren) {
          // selector in parens should not be affected by outer selector
          // flags (breaks only interpolated selectors - see #1973)
          context.firstSelector = true;
      }
      value = value.toCSS ? value.toCSS(context) : value;
      context.firstSelector = firstSelector;
      if (value === '' && this.combinator.value.charAt(0) === '&') {
          return '';
      } else {
          return this.combinator.toCSS(context) + value;
      }
  };
  module.exports = Element;
  
  },{"./combinator":54,"./node":73,"./paren":75}],62:[function(require,module,exports){
  var Node = require("./node"),
      Paren = require("./paren"),
      Comment = require("./comment");
  
  var Expression = function (value) {
      this.value = value;
      if (!value) {
          throw new Error("Expression requires an array parameter");
      }
  };
  Expression.prototype = new Node();
  Expression.prototype.type = "Expression";
  Expression.prototype.accept = function (visitor) {
      this.value = visitor.visitArray(this.value);
  };
  Expression.prototype.eval = function (context) {
      var returnValue,
          inParenthesis = this.parens && !this.parensInOp,
          doubleParen = false;
      if (inParenthesis) {
          context.inParenthesis();
      }
      if (this.value.length > 1) {
          returnValue = new Expression(this.value.map(function (e) {
              return e.eval(context);
          }));
      } else if (this.value.length === 1) {
          if (this.value[0].parens && !this.value[0].parensInOp) {
              doubleParen = true;
          }
          returnValue = this.value[0].eval(context);
      } else {
          returnValue = this;
      }
      if (inParenthesis) {
          context.outOfParenthesis();
      }
      if (this.parens && this.parensInOp && !(context.isMathOn()) && !doubleParen) {
          returnValue = new Paren(returnValue);
      }
      return returnValue;
  };
  Expression.prototype.genCSS = function (context, output) {
      for (var i = 0; i < this.value.length; i++) {
          this.value[i].genCSS(context, output);
          if (i + 1 < this.value.length) {
              output.add(" ");
          }
      }
  };
  Expression.prototype.throwAwayComments = function () {
      this.value = this.value.filter(function(v) {
          return !(v instanceof Comment);
      });
  };
  module.exports = Expression;
  
  },{"./comment":55,"./node":73,"./paren":75}],63:[function(require,module,exports){
  var Node = require("./node"),
      Selector = require("./selector");
  
  var Extend = function Extend(selector, option, index, currentFileInfo, visibilityInfo) {
      this.selector = selector;
      this.option = option;
      this.object_id = Extend.next_id++;
      this.parent_ids = [this.object_id];
      this._index = index;
      this._fileInfo = currentFileInfo;
      this.copyVisibilityInfo(visibilityInfo);
      this.allowRoot = true;
  
      switch (option) {
          case "all":
              this.allowBefore = true;
              this.allowAfter = true;
              break;
          default:
              this.allowBefore = false;
              this.allowAfter = false;
              break;
      }
      this.setParent(this.selector, this);
  };
  Extend.next_id = 0;
  
  Extend.prototype = new Node();
  Extend.prototype.type = "Extend";
  Extend.prototype.accept = function (visitor) {
      this.selector = visitor.visit(this.selector);
  };
  Extend.prototype.eval = function (context) {
      return new Extend(this.selector.eval(context), this.option, this.getIndex(), this.fileInfo(), this.visibilityInfo());
  };
  Extend.prototype.clone = function (context) {
      return new Extend(this.selector, this.option, this.getIndex(), this.fileInfo(), this.visibilityInfo());
  };
  // it concatenates (joins) all selectors in selector array
  Extend.prototype.findSelfSelectors = function (selectors) {
      var selfElements = [],
          i,
          selectorElements;
  
      for (i = 0; i < selectors.length; i++) {
          selectorElements = selectors[i].elements;
          // duplicate the logic in genCSS function inside the selector node.
          // future TODO - move both logics into the selector joiner visitor
          if (i > 0 && selectorElements.length && selectorElements[0].combinator.value === "") {
              selectorElements[0].combinator.value = ' ';
          }
          selfElements = selfElements.concat(selectors[i].elements);
      }
  
      this.selfSelectors = [new Selector(selfElements)];
      this.selfSelectors[0].copyVisibilityInfo(this.visibilityInfo());
  };
  module.exports = Extend;
  
  },{"./node":73,"./selector":79}],64:[function(require,module,exports){
  var Node = require("./node"),
      Media = require("./media"),
      URL = require("./url"),
      Quoted = require("./quoted"),
      Ruleset = require("./ruleset"),
      Anonymous = require("./anonymous"),
      utils = require("../utils"),
      LessError = require("../less-error");
  
  //
  // CSS @import node
  //
  // The general strategy here is that we don't want to wait
  // for the parsing to be completed, before we start importing
  // the file. That's because in the context of a browser,
  // most of the time will be spent waiting for the server to respond.
  //
  // On creation, we push the import path to our import queue, though
  // `import,push`, we also pass it a callback, which it'll call once
  // the file has been fetched, and parsed.
  //
  var Import = function (path, features, options, index, currentFileInfo, visibilityInfo) {
      this.options = options;
      this._index = index;
      this._fileInfo = currentFileInfo;
      this.path = path;
      this.features = features;
      this.allowRoot = true;
  
      if (this.options.less !== undefined || this.options.inline) {
          this.css = !this.options.less || this.options.inline;
      } else {
          var pathValue = this.getPath();
          if (pathValue && /[#\.\&\?]css([\?;].*)?$/.test(pathValue)) {
              this.css = true;
          }
      }
      this.copyVisibilityInfo(visibilityInfo);
      this.setParent(this.features, this);
      this.setParent(this.path, this);
  };
  
  //
  // The actual import node doesn't return anything, when converted to CSS.
  // The reason is that it's used at the evaluation stage, so that the rules
  // it imports can be treated like any other rules.
  //
  // In `eval`, we make sure all Import nodes get evaluated, recursively, so
  // we end up with a flat structure, which can easily be imported in the parent
  // ruleset.
  //
  Import.prototype = new Node();
  Import.prototype.type = "Import";
  Import.prototype.accept = function (visitor) {
      if (this.features) {
          this.features = visitor.visit(this.features);
      }
      this.path = visitor.visit(this.path);
      if (!this.options.isPlugin && !this.options.inline && this.root) {
          this.root = visitor.visit(this.root);
      }
  };
  Import.prototype.genCSS = function (context, output) {
      if (this.css && this.path._fileInfo.reference === undefined) {
          output.add("@import ", this._fileInfo, this._index);
          this.path.genCSS(context, output);
          if (this.features) {
              output.add(" ");
              this.features.genCSS(context, output);
          }
          output.add(';');
      }
  };
  Import.prototype.getPath = function () {
      return (this.path instanceof URL) ?
          this.path.value.value : this.path.value;
  };
  Import.prototype.isVariableImport = function () {
      var path = this.path;
      if (path instanceof URL) {
          path = path.value;
      }
      if (path instanceof Quoted) {
          return path.containsVariables();
      }
  
      return true;
  };
  Import.prototype.evalForImport = function (context) {
      var path = this.path;
  
      if (path instanceof URL) {
          path = path.value;
      }
  
      return new Import(path.eval(context), this.features, this.options, this._index, this._fileInfo, this.visibilityInfo());
  };
  Import.prototype.evalPath = function (context) {
      var path = this.path.eval(context);
      var rootpath = this._fileInfo && this._fileInfo.rootpath;
  
      if (!(path instanceof URL)) {
          if (rootpath) {
              var pathValue = path.value;
              // Add the base path if the import is relative
              if (pathValue && context.isPathRelative(pathValue)) {
                  path.value = rootpath + pathValue;
              }
          }
          path.value = context.normalizePath(path.value);
      }
  
      return path;
  };
  Import.prototype.eval = function (context) {
      var result = this.doEval(context);
      if (this.options.reference || this.blocksVisibility()) {
          if (result.length || result.length === 0) {
              result.forEach(function (node) {
                  node.addVisibilityBlock();
              }
              );
          } else {
              result.addVisibilityBlock();
          }
      }
      return result;
  };
  Import.prototype.doEval = function (context) {
      var ruleset, registry,
          features = this.features && this.features.eval(context);
  
      if (this.options.isPlugin) {
          if (this.root && this.root.eval) {
              try {
                  this.root.eval(context);
              }
              catch (e) {
                  e.message = "Plugin error during evaluation";
                  throw new LessError(e, this.root.imports, this.root.filename);
              }
          }
          registry = context.frames[0] && context.frames[0].functionRegistry;
          if ( registry && this.root && this.root.functions ) {
              registry.addMultiple( this.root.functions );
          }
  
          return [];
      }
  
      if (this.skip) {
          if (typeof this.skip === "function") {
              this.skip = this.skip();
          }
          if (this.skip) {
              return [];
          }
      }
      if (this.options.inline) {
          var contents = new Anonymous(this.root, 0,
              {
                  filename: this.importedFilename,
                  reference: this.path._fileInfo && this.path._fileInfo.reference
              }, true, true);
  
          return this.features ? new Media([contents], this.features.value) : [contents];
      } else if (this.css) {
          var newImport = new Import(this.evalPath(context), features, this.options, this._index);
          if (!newImport.css && this.error) {
              throw this.error;
          }
          return newImport;
      } else {
          ruleset = new Ruleset(null, utils.copyArray(this.root.rules));
          ruleset.evalImports(context);
  
          return this.features ? new Media(ruleset.rules, this.features.value) : ruleset.rules;
      }
  };
  module.exports = Import;
  
  },{"../less-error":36,"../utils":86,"./anonymous":48,"./media":69,"./node":73,"./quoted":77,"./ruleset":78,"./url":82}],65:[function(require,module,exports){
  var tree = Object.create(null);
  
  tree.Node = require('./node');
  tree.Color = require('./color');
  tree.AtRule = require('./atrule');
  tree.DetachedRuleset = require('./detached-ruleset');
  tree.Operation = require('./operation');
  tree.Dimension = require('./dimension');
  tree.Unit = require('./unit');
  tree.Keyword = require('./keyword');
  tree.Variable = require('./variable');
  tree.Property = require('./property');
  tree.Ruleset = require('./ruleset');
  tree.Element = require('./element');
  tree.Attribute = require('./attribute');
  tree.Combinator = require('./combinator');
  tree.Selector = require('./selector');
  tree.Quoted = require('./quoted');
  tree.Expression = require('./expression');
  tree.Declaration = require('./declaration');
  tree.Call = require('./call');
  tree.URL = require('./url');
  tree.Import = require('./import');
  tree.mixin = {
      Call: require('./mixin-call'),
      Definition: require('./mixin-definition')
  };
  tree.Comment = require('./comment');
  tree.Anonymous = require('./anonymous');
  tree.Value = require('./value');
  tree.JavaScript = require('./javascript');
  tree.Assignment = require('./assignment');
  tree.Condition = require('./condition');
  tree.Paren = require('./paren');
  tree.Media = require('./media');
  tree.UnicodeDescriptor = require('./unicode-descriptor');
  tree.Negative = require('./negative');
  tree.Extend = require('./extend');
  tree.VariableCall = require('./variable-call');
  
  module.exports = tree;
  
  },{"./anonymous":48,"./assignment":49,"./atrule":50,"./attribute":51,"./call":52,"./color":53,"./combinator":54,"./comment":55,"./condition":56,"./declaration":58,"./detached-ruleset":59,"./dimension":60,"./element":61,"./expression":62,"./extend":63,"./import":64,"./javascript":66,"./keyword":68,"./media":69,"./mixin-call":70,"./mixin-definition":71,"./negative":72,"./node":73,"./operation":74,"./paren":75,"./property":76,"./quoted":77,"./ruleset":78,"./selector":79,"./unicode-descriptor":80,"./unit":81,"./url":82,"./value":83,"./variable":85,"./variable-call":84}],66:[function(require,module,exports){
  var JsEvalNode = require("./js-eval-node"),
      Dimension = require("./dimension"),
      Quoted = require("./quoted"),
      Anonymous = require("./anonymous");
  
  var JavaScript = function (string, escaped, index, currentFileInfo) {
      this.escaped = escaped;
      this.expression = string;
      this._index = index;
      this._fileInfo = currentFileInfo;
  };
  JavaScript.prototype = new JsEvalNode();
  JavaScript.prototype.type = "JavaScript";
  JavaScript.prototype.eval = function(context) {
      var result = this.evaluateJavaScript(this.expression, context);
  
      if (typeof result === 'number') {
          return new Dimension(result);
      } else if (typeof result === 'string') {
          return new Quoted('"' + result + '"', result, this.escaped, this._index);
      } else if (Array.isArray(result)) {
          return new Anonymous(result.join(', '));
      } else {
          return new Anonymous(result);
      }
  };
  
  module.exports = JavaScript;
  
  },{"./anonymous":48,"./dimension":60,"./js-eval-node":67,"./quoted":77}],67:[function(require,module,exports){
  var Node = require("./node"),
      Variable = require("./variable");
  
  var JsEvalNode = function() {
  };
  JsEvalNode.prototype = new Node();
  
  JsEvalNode.prototype.evaluateJavaScript = function (expression, context) {
      var result,
          that = this,
          evalContext = {};
  
      if (!context.javascriptEnabled) {
          throw { message: "Inline JavaScript is not enabled. Is it set in your options?",
              filename: this.fileInfo().filename,
              index: this.getIndex() };
      }
  
      expression = expression.replace(/@\{([\w-]+)\}/g, function (_, name) {
          return that.jsify(new Variable('@' + name, that.getIndex(), that.fileInfo()).eval(context));
      });
  
      try {
          expression = new Function('return (' + expression + ')');
      } catch (e) {
          throw { message: "JavaScript evaluation error: " + e.message + " from `" + expression + "`" ,
              filename: this.fileInfo().filename,
              index: this.getIndex() };
      }
  
      var variables = context.frames[0].variables();
      for (var k in variables) {
          if (variables.hasOwnProperty(k)) {
              /* jshint loopfunc:true */
              evalContext[k.slice(1)] = {
                  value: variables[k].value,
                  toJS: function () {
                      return this.value.eval(context).toCSS();
                  }
              };
          }
      }
  
      try {
          result = expression.call(evalContext);
      } catch (e) {
          throw { message: "JavaScript evaluation error: '" + e.name + ': ' + e.message.replace(/["]/g, "'") + "'" ,
              filename: this.fileInfo().filename,
              index: this.getIndex() };
      }
      return result;
  };
  JsEvalNode.prototype.jsify = function (obj) {
      if (Array.isArray(obj.value) && (obj.value.length > 1)) {
          return '[' + obj.value.map(function (v) { return v.toCSS(); }).join(', ') + ']';
      } else {
          return obj.toCSS();
      }
  };
  
  module.exports = JsEvalNode;
  
  },{"./node":73,"./variable":85}],68:[function(require,module,exports){
  var Node = require("./node");
  
  var Keyword = function (value) { this.value = value; };
  Keyword.prototype = new Node();
  Keyword.prototype.type = "Keyword";
  Keyword.prototype.genCSS = function (context, output) {
      if (this.value === '%') { throw { type: "Syntax", message: "Invalid % without number" }; }
      output.add(this.value);
  };
  
  Keyword.True = new Keyword('true');
  Keyword.False = new Keyword('false');
  
  module.exports = Keyword;
  
  },{"./node":73}],69:[function(require,module,exports){
  var Ruleset = require("./ruleset"),
      Value = require("./value"),
      Selector = require("./selector"),
      Anonymous = require("./anonymous"),
      Expression = require("./expression"),
      AtRule = require("./atrule"),
      utils = require("../utils");
  
  var Media = function (value, features, index, currentFileInfo, visibilityInfo) {
      this._index = index;
      this._fileInfo = currentFileInfo;
  
      var selectors = (new Selector([], null, null, this._index, this._fileInfo)).createEmptySelectors();
  
      this.features = new Value(features);
      this.rules = [new Ruleset(selectors, value)];
      this.rules[0].allowImports = true;
      this.copyVisibilityInfo(visibilityInfo);
      this.allowRoot = true;
      this.setParent(selectors, this);
      this.setParent(this.features, this);
      this.setParent(this.rules, this);
  };
  Media.prototype = new AtRule();
  Media.prototype.type = "Media";
  Media.prototype.isRulesetLike = function() { return true; };
  Media.prototype.accept = function (visitor) {
      if (this.features) {
          this.features = visitor.visit(this.features);
      }
      if (this.rules) {
          this.rules = visitor.visitArray(this.rules);
      }
  };
  Media.prototype.genCSS = function (context, output) {
      output.add('@media ', this._fileInfo, this._index);
      this.features.genCSS(context, output);
      this.outputRuleset(context, output, this.rules);
  };
  Media.prototype.eval = function (context) {
      if (!context.mediaBlocks) {
          context.mediaBlocks = [];
          context.mediaPath = [];
      }
  
      var media = new Media(null, [], this._index, this._fileInfo, this.visibilityInfo());
      if (this.debugInfo) {
          this.rules[0].debugInfo = this.debugInfo;
          media.debugInfo = this.debugInfo;
      }
      
      media.features = this.features.eval(context);
  
      context.mediaPath.push(media);
      context.mediaBlocks.push(media);
  
      this.rules[0].functionRegistry = context.frames[0].functionRegistry.inherit();
      context.frames.unshift(this.rules[0]);
      media.rules = [this.rules[0].eval(context)];
      context.frames.shift();
  
      context.mediaPath.pop();
  
      return context.mediaPath.length === 0 ? media.evalTop(context) :
                  media.evalNested(context);
  };
  Media.prototype.evalTop = function (context) {
      var result = this;
  
      // Render all dependent Media blocks.
      if (context.mediaBlocks.length > 1) {
          var selectors = (new Selector([], null, null, this.getIndex(), this.fileInfo())).createEmptySelectors();
          result = new Ruleset(selectors, context.mediaBlocks);
          result.multiMedia = true;
          result.copyVisibilityInfo(this.visibilityInfo());
          this.setParent(result, this);
      }
  
      delete context.mediaBlocks;
      delete context.mediaPath;
  
      return result;
  };
  Media.prototype.evalNested = function (context) {
      var i, value,
          path = context.mediaPath.concat([this]);
  
      // Extract the media-query conditions separated with `,` (OR).
      for (i = 0; i < path.length; i++) {
          value = path[i].features instanceof Value ?
                      path[i].features.value : path[i].features;
          path[i] = Array.isArray(value) ? value : [value];
      }
  
      // Trace all permutations to generate the resulting media-query.
      //
      // (a, b and c) with nested (d, e) ->
      //    a and d
      //    a and e
      //    b and c and d
      //    b and c and e
      this.features = new Value(this.permute(path).map(function (path) {
          path = path.map(function (fragment) {
              return fragment.toCSS ? fragment : new Anonymous(fragment);
          });
  
          for (i = path.length - 1; i > 0; i--) {
              path.splice(i, 0, new Anonymous("and"));
          }
  
          return new Expression(path);
      }));
      this.setParent(this.features, this);
  
      // Fake a tree-node that doesn't output anything.
      return new Ruleset([], []);
  };
  Media.prototype.permute = function (arr) {
      if (arr.length === 0) {
          return [];
      } else if (arr.length === 1) {
          return arr[0];
      } else {
          var result = [];
          var rest = this.permute(arr.slice(1));
          for (var i = 0; i < rest.length; i++) {
              for (var j = 0; j < arr[0].length; j++) {
                  result.push([arr[0][j]].concat(rest[i]));
              }
          }
          return result;
      }
  };
  Media.prototype.bubbleSelectors = function (selectors) {
      if (!selectors) {
          return;
      }
      this.rules = [new Ruleset(utils.copyArray(selectors), [this.rules[0]])];
      this.setParent(this.rules, this);
  };
  module.exports = Media;
  
  },{"../utils":86,"./anonymous":48,"./atrule":50,"./expression":62,"./ruleset":78,"./selector":79,"./value":83}],70:[function(require,module,exports){
  var Node = require("./node"),
      Selector = require("./selector"),
      MixinDefinition = require("./mixin-definition"),
      defaultFunc = require("../functions/default");
  
  var MixinCall = function (elements, args, index, currentFileInfo, important) {
      this.selector = new Selector(elements);
      this.arguments = args || [];
      this._index = index;
      this._fileInfo = currentFileInfo;
      this.important = important;
      this.allowRoot = true;
      this.setParent(this.selector, this);
  };
  MixinCall.prototype = new Node();
  MixinCall.prototype.type = "MixinCall";
  MixinCall.prototype.accept = function (visitor) {
      if (this.selector) {
          this.selector = visitor.visit(this.selector);
      }
      if (this.arguments.length) {
          this.arguments = visitor.visitArray(this.arguments);
      }
  };
  MixinCall.prototype.eval = function (context) {
      var mixins, mixin, mixinPath, args = [], arg, argValue,
          rules = [], match = false, i, m, f, isRecursive, isOneFound,
          candidates = [], candidate, conditionResult = [], defaultResult, defFalseEitherCase = -1,
          defNone = 0, defTrue = 1, defFalse = 2, count, originalRuleset, noArgumentsFilter;
  
      function calcDefGroup(mixin, mixinPath) {
          var f, p, namespace;
  
          for (f = 0; f < 2; f++) {
              conditionResult[f] = true;
              defaultFunc.value(f);
              for (p = 0; p < mixinPath.length && conditionResult[f]; p++) {
                  namespace = mixinPath[p];
                  if (namespace.matchCondition) {
                      conditionResult[f] = conditionResult[f] && namespace.matchCondition(null, context);
                  }
              }
              if (mixin.matchCondition) {
                  conditionResult[f] = conditionResult[f] && mixin.matchCondition(args, context);
              }
          }
          if (conditionResult[0] || conditionResult[1]) {
              if (conditionResult[0] != conditionResult[1]) {
                  return conditionResult[1] ?
                      defTrue : defFalse;
              }
  
              return defNone;
          }
          return defFalseEitherCase;
      }
  
      for (i = 0; i < this.arguments.length; i++) {
          arg = this.arguments[i];
          argValue = arg.value.eval(context);
          if (arg.expand && Array.isArray(argValue.value)) {
              argValue = argValue.value;
              for (m = 0; m < argValue.length; m++) {
                  args.push({value: argValue[m]});
              }
          } else {
              args.push({name: arg.name, value: argValue});
          }
      }
  
      noArgumentsFilter = function(rule) {return rule.matchArgs(null, context);};
  
      for (i = 0; i < context.frames.length; i++) {
          if ((mixins = context.frames[i].find(this.selector, null, noArgumentsFilter)).length > 0) {
              isOneFound = true;
  
              // To make `default()` function independent of definition order we have two "subpasses" here.
              // At first we evaluate each guard *twice* (with `default() == true` and `default() == false`),
              // and build candidate list with corresponding flags. Then, when we know all possible matches,
              // we make a final decision.
  
              for (m = 0; m < mixins.length; m++) {
                  mixin = mixins[m].rule;
                  mixinPath = mixins[m].path;
                  isRecursive = false;
                  for (f = 0; f < context.frames.length; f++) {
                      if ((!(mixin instanceof MixinDefinition)) && mixin === (context.frames[f].originalRuleset || context.frames[f])) {
                          isRecursive = true;
                          break;
                      }
                  }
                  if (isRecursive) {
                      continue;
                  }
  
                  if (mixin.matchArgs(args, context)) {
                      candidate = {mixin: mixin, group: calcDefGroup(mixin, mixinPath)};
  
                      if (candidate.group !== defFalseEitherCase) {
                          candidates.push(candidate);
                      }
  
                      match = true;
                  }
              }
  
              defaultFunc.reset();
  
              count = [0, 0, 0];
              for (m = 0; m < candidates.length; m++) {
                  count[candidates[m].group]++;
              }
  
              if (count[defNone] > 0) {
                  defaultResult = defFalse;
              } else {
                  defaultResult = defTrue;
                  if ((count[defTrue] + count[defFalse]) > 1) {
                      throw { type: 'Runtime',
                          message: 'Ambiguous use of `default()` found when matching for `' + this.format(args) + '`',
                          index: this.getIndex(), filename: this.fileInfo().filename };
                  }
              }
  
              for (m = 0; m < candidates.length; m++) {
                  candidate = candidates[m].group;
                  if ((candidate === defNone) || (candidate === defaultResult)) {
                      try {
                          mixin = candidates[m].mixin;
                          if (!(mixin instanceof MixinDefinition)) {
                              originalRuleset = mixin.originalRuleset || mixin;
                              mixin = new MixinDefinition("", [], mixin.rules, null, false, null, originalRuleset.visibilityInfo());
                              mixin.originalRuleset = originalRuleset;
                          }
                          var newRules = mixin.evalCall(context, args, this.important).rules;
                          this._setVisibilityToReplacement(newRules);
                          Array.prototype.push.apply(rules, newRules);
                      } catch (e) {
                          throw { message: e.message, index: this.getIndex(), filename: this.fileInfo().filename, stack: e.stack };
                      }
                  }
              }
  
              if (match) {
                  return rules;
              }
          }
      }
      if (isOneFound) {
          throw { type:    'Runtime',
              message: 'No matching definition was found for `' + this.format(args) + '`',
              index:   this.getIndex(), filename: this.fileInfo().filename };
      } else {
          throw { type:    'Name',
              message: this.selector.toCSS().trim() + " is undefined",
              index:   this.getIndex(), filename: this.fileInfo().filename };
      }
  };
  
  MixinCall.prototype._setVisibilityToReplacement = function (replacement) {
      var i, rule;
      if (this.blocksVisibility()) {
          for (i = 0; i < replacement.length; i++) {
              rule = replacement[i];
              rule.addVisibilityBlock();
          }
      }
  };
  MixinCall.prototype.format = function (args) {
      return this.selector.toCSS().trim() + '(' +
          (args ? args.map(function (a) {
              var argValue = "";
              if (a.name) {
                  argValue += a.name + ":";
              }
              if (a.value.toCSS) {
                  argValue += a.value.toCSS();
              } else {
                  argValue += "???";
              }
              return argValue;
          }).join(', ') : "") + ")";
  };
  module.exports = MixinCall;
  
  },{"../functions/default":24,"./mixin-definition":71,"./node":73,"./selector":79}],71:[function(require,module,exports){
  var Selector = require("./selector"),
      Element = require("./element"),
      Ruleset = require("./ruleset"),
      Declaration = require("./declaration"),
      Expression = require("./expression"),
      contexts = require("../contexts"),
      utils = require("../utils");
  
  var Definition = function (name, params, rules, condition, variadic, frames, visibilityInfo) {
      this.name = name;
      this.selectors = [new Selector([new Element(null, name, this._index, this._fileInfo)])];
      this.params = params;
      this.condition = condition;
      this.variadic = variadic;
      this.arity = params.length;
      this.rules = rules;
      this._lookups = {};
      var optionalParameters = [];
      this.required = params.reduce(function (count, p) {
          if (!p.name || (p.name && !p.value)) {
              return count + 1;
          }
          else {
              optionalParameters.push(p.name);
              return count;
          }
      }, 0);
      this.optionalParameters = optionalParameters;
      this.frames = frames;
      this.copyVisibilityInfo(visibilityInfo);
      this.allowRoot = true;
  };
  Definition.prototype = new Ruleset();
  Definition.prototype.type = "MixinDefinition";
  Definition.prototype.evalFirst = true;
  Definition.prototype.accept = function (visitor) {
      if (this.params && this.params.length) {
          this.params = visitor.visitArray(this.params);
      }
      this.rules = visitor.visitArray(this.rules);
      if (this.condition) {
          this.condition = visitor.visit(this.condition);
      }
  };
  Definition.prototype.evalParams = function (context, mixinEnv, args, evaldArguments) {
      /* jshint boss:true */
      var frame = new Ruleset(null, null),
          varargs, arg,
          params = utils.copyArray(this.params),
          i, j, val, name, isNamedFound, argIndex, argsLength = 0;
  
      if (mixinEnv.frames && mixinEnv.frames[0] && mixinEnv.frames[0].functionRegistry) {
          frame.functionRegistry = mixinEnv.frames[0].functionRegistry.inherit();
      }
      mixinEnv = new contexts.Eval(mixinEnv, [frame].concat(mixinEnv.frames));
  
      if (args) {
          args = utils.copyArray(args);
          argsLength = args.length;
  
          for (i = 0; i < argsLength; i++) {
              arg = args[i];
              if (name = (arg && arg.name)) {
                  isNamedFound = false;
                  for (j = 0; j < params.length; j++) {
                      if (!evaldArguments[j] && name === params[j].name) {
                          evaldArguments[j] = arg.value.eval(context);
                          frame.prependRule(new Declaration(name, arg.value.eval(context)));
                          isNamedFound = true;
                          break;
                      }
                  }
                  if (isNamedFound) {
                      args.splice(i, 1);
                      i--;
                      continue;
                  } else {
                      throw { type: 'Runtime', message: "Named argument for " + this.name +
                          ' ' + args[i].name + ' not found' };
                  }
              }
          }
      }
      argIndex = 0;
      for (i = 0; i < params.length; i++) {
          if (evaldArguments[i]) { continue; }
  
          arg = args && args[argIndex];
  
          if (name = params[i].name) {
              if (params[i].variadic) {
                  varargs = [];
                  for (j = argIndex; j < argsLength; j++) {
                      varargs.push(args[j].value.eval(context));
                  }
                  frame.prependRule(new Declaration(name, new Expression(varargs).eval(context)));
              } else {
                  val = arg && arg.value;
                  if (val) {
                      val = val.eval(context);
                  } else if (params[i].value) {
                      val = params[i].value.eval(mixinEnv);
                      frame.resetCache();
                  } else {
                      throw { type: 'Runtime', message: "wrong number of arguments for " + this.name +
                          ' (' + argsLength + ' for ' + this.arity + ')' };
                  }
  
                  frame.prependRule(new Declaration(name, val));
                  evaldArguments[i] = val;
              }
          }
  
          if (params[i].variadic && args) {
              for (j = argIndex; j < argsLength; j++) {
                  evaldArguments[j] = args[j].value.eval(context);
              }
          }
          argIndex++;
      }
  
      return frame;
  };
  Definition.prototype.makeImportant = function() {
      var rules = !this.rules ? this.rules : this.rules.map(function (r) {
          if (r.makeImportant) {
              return r.makeImportant(true);
          } else {
              return r;
          }
      });
      var result = new Definition(this.name, this.params, rules, this.condition, this.variadic, this.frames);
      return result;
  };
  Definition.prototype.eval = function (context) {
      return new Definition(this.name, this.params, this.rules, this.condition, this.variadic, this.frames || utils.copyArray(context.frames));
  };
  Definition.prototype.evalCall = function (context, args, important) {
      var _arguments = [],
          mixinFrames = this.frames ? this.frames.concat(context.frames) : context.frames,
          frame = this.evalParams(context, new contexts.Eval(context, mixinFrames), args, _arguments),
          rules, ruleset;
  
      frame.prependRule(new Declaration('@arguments', new Expression(_arguments).eval(context)));
  
      rules = utils.copyArray(this.rules);
  
      ruleset = new Ruleset(null, rules);
      ruleset.originalRuleset = this;
      ruleset = ruleset.eval(new contexts.Eval(context, [this, frame].concat(mixinFrames)));
      if (important) {
          ruleset = ruleset.makeImportant();
      }
      return ruleset;
  };
  Definition.prototype.matchCondition = function (args, context) {
      if (this.condition && !this.condition.eval(
          new contexts.Eval(context,
              [this.evalParams(context, /* the parameter variables */
                  new contexts.Eval(context, this.frames ? this.frames.concat(context.frames) : context.frames), args, [])]
              .concat(this.frames || []) // the parent namespace/mixin frames
              .concat(context.frames)))) { // the current environment frames
          return false;
      }
      return true;
  };
  Definition.prototype.matchArgs = function (args, context) {
      var allArgsCnt = (args && args.length) || 0, len, optionalParameters = this.optionalParameters;
      var requiredArgsCnt = !args ? 0 : args.reduce(function (count, p) {
          if (optionalParameters.indexOf(p.name) < 0) {
              return count + 1;
          } else {
              return count;
          }
      }, 0);
  
      if (!this.variadic) {
          if (requiredArgsCnt < this.required) {
              return false;
          }
          if (allArgsCnt > this.params.length) {
              return false;
          }
      } else {
          if (requiredArgsCnt < (this.required - 1)) {
              return false;
          }
      }
  
      // check patterns
      len = Math.min(requiredArgsCnt, this.arity);
  
      for (var i = 0; i < len; i++) {
          if (!this.params[i].name && !this.params[i].variadic) {
              if (args[i].value.eval(context).toCSS() != this.params[i].value.eval(context).toCSS()) {
                  return false;
              }
          }
      }
      return true;
  };
  module.exports = Definition;
  
  },{"../contexts":12,"../utils":86,"./declaration":58,"./element":61,"./expression":62,"./ruleset":78,"./selector":79}],72:[function(require,module,exports){
  var Node = require("./node"),
      Operation = require("./operation"),
      Dimension = require("./dimension");
  
  var Negative = function (node) {
      this.value = node;
  };
  Negative.prototype = new Node();
  Negative.prototype.type = "Negative";
  Negative.prototype.genCSS = function (context, output) {
      output.add('-');
      this.value.genCSS(context, output);
  };
  Negative.prototype.eval = function (context) {
      if (context.isMathOn()) {
          return (new Operation('*', [new Dimension(-1), this.value])).eval(context);
      }
      return new Negative(this.value.eval(context));
  };
  module.exports = Negative;
  
  },{"./dimension":60,"./node":73,"./operation":74}],73:[function(require,module,exports){
  var Node = function() {
      this.parent = null;
      this.visibilityBlocks = undefined;
      this.nodeVisible = undefined;
      this.rootNode = null;
      this.parsed = null;
  
      var self = this;
      Object.defineProperty(this, "currentFileInfo", {
          get: function() { return self.fileInfo(); }
      });
      Object.defineProperty(this, "index", {
          get: function() { return self.getIndex(); }
      });
  
  };
  Node.prototype.setParent = function(nodes, parent) {
      function set(node) {
          if (node && node instanceof Node) {
              node.parent = parent;
          }
      }
      if (Array.isArray(nodes)) {
          nodes.forEach(set);
      }
      else {
          set(nodes);
      }
  };
  Node.prototype.getIndex = function() {
      return this._index || (this.parent && this.parent.getIndex()) || 0;
  };
  Node.prototype.fileInfo = function() {
      return this._fileInfo || (this.parent && this.parent.fileInfo()) || {};
  };
  Node.prototype.isRulesetLike = function() { return false; };
  Node.prototype.toCSS = function (context) {
      var strs = [];
      this.genCSS(context, {
          add: function(chunk, fileInfo, index) {
              strs.push(chunk);
          },
          isEmpty: function () {
              return strs.length === 0;
          }
      });
      return strs.join('');
  };
  Node.prototype.genCSS = function (context, output) {
      output.add(this.value);
  };
  Node.prototype.accept = function (visitor) {
      this.value = visitor.visit(this.value);
  };
  Node.prototype.eval = function () { return this; };
  Node.prototype._operate = function (context, op, a, b) {
      switch (op) {
          case '+': return a + b;
          case '-': return a - b;
          case '*': return a * b;
          case '/': return a / b;
      }
  };
  Node.prototype.fround = function(context, value) {
      var precision = context && context.numPrecision;
      // add "epsilon" to ensure numbers like 1.000000005 (represented as 1.000000004999...) are properly rounded:
      return (precision) ? Number((value + 2e-16).toFixed(precision)) : value;
  };
  Node.compare = function (a, b) {
      /* returns:
       -1: a < b
       0: a = b
       1: a > b
       and *any* other value for a != b (e.g. undefined, NaN, -2 etc.) */
  
      if ((a.compare) &&
          // for "symmetric results" force toCSS-based comparison
          // of Quoted or Anonymous if either value is one of those
          !(b.type === "Quoted" || b.type === "Anonymous")) {
          return a.compare(b);
      } else if (b.compare) {
          return -b.compare(a);
      } else if (a.type !== b.type) {
          return undefined;
      }
  
      a = a.value;
      b = b.value;
      if (!Array.isArray(a)) {
          return a === b ? 0 : undefined;
      }
      if (a.length !== b.length) {
          return undefined;
      }
      for (var i = 0; i < a.length; i++) {
          if (Node.compare(a[i], b[i]) !== 0) {
              return undefined;
          }
      }
      return 0;
  };
  
  Node.numericCompare = function (a, b) {
      return a  <  b ? -1
          : a === b ?  0
          : a  >  b ?  1 : undefined;
  };
  // Returns true if this node represents root of ast imported by reference
  Node.prototype.blocksVisibility = function () {
      if (this.visibilityBlocks == null) {
          this.visibilityBlocks = 0;
      }
      return this.visibilityBlocks !== 0;
  };
  Node.prototype.addVisibilityBlock = function () {
      if (this.visibilityBlocks == null) {
          this.visibilityBlocks = 0;
      }
      this.visibilityBlocks = this.visibilityBlocks + 1;
  };
  Node.prototype.removeVisibilityBlock = function () {
      if (this.visibilityBlocks == null) {
          this.visibilityBlocks = 0;
      }
      this.visibilityBlocks = this.visibilityBlocks - 1;
  };
  // Turns on node visibility - if called node will be shown in output regardless
  // of whether it comes from import by reference or not
  Node.prototype.ensureVisibility = function () {
      this.nodeVisible = true;
  };
  // Turns off node visibility - if called node will NOT be shown in output regardless
  // of whether it comes from import by reference or not
  Node.prototype.ensureInvisibility = function () {
      this.nodeVisible = false;
  };
  // return values:
  // false - the node must not be visible
  // true - the node must be visible
  // undefined or null - the node has the same visibility as its parent
  Node.prototype.isVisible = function () {
      return this.nodeVisible;
  };
  Node.prototype.visibilityInfo = function() {
      return {
          visibilityBlocks: this.visibilityBlocks,
          nodeVisible: this.nodeVisible
      };
  };
  Node.prototype.copyVisibilityInfo = function(info) {
      if (!info) {
          return;
      }
      this.visibilityBlocks = info.visibilityBlocks;
      this.nodeVisible = info.nodeVisible;
  };
  module.exports = Node;
  
  },{}],74:[function(require,module,exports){
  var Node = require("./node"),
      Color = require("./color"),
      Dimension = require("./dimension");
  
  var Operation = function (op, operands, isSpaced) {
      this.op = op.trim();
      this.operands = operands;
      this.isSpaced = isSpaced;
  };
  Operation.prototype = new Node();
  Operation.prototype.type = "Operation";
  Operation.prototype.accept = function (visitor) {
      this.operands = visitor.visit(this.operands);
  };
  Operation.prototype.eval = function (context) {
      var a = this.operands[0].eval(context),
          b = this.operands[1].eval(context);
  
      if (context.isMathOn()) {
          if (a instanceof Dimension && b instanceof Color) {
              a = a.toColor();
          }
          if (b instanceof Dimension && a instanceof Color) {
              b = b.toColor();
          }
          if (!a.operate) {
              throw { type: "Operation",
                  message: "Operation on an invalid type" };
          }
  
          return a.operate(context, this.op, b);
      } else {
          return new Operation(this.op, [a, b], this.isSpaced);
      }
  };
  Operation.prototype.genCSS = function (context, output) {
      this.operands[0].genCSS(context, output);
      if (this.isSpaced) {
          output.add(" ");
      }
      output.add(this.op);
      if (this.isSpaced) {
          output.add(" ");
      }
      this.operands[1].genCSS(context, output);
  };
  
  module.exports = Operation;
  
  },{"./color":53,"./dimension":60,"./node":73}],75:[function(require,module,exports){
  var Node = require("./node");
  
  var Paren = function (node) {
      this.value = node;
  };
  Paren.prototype = new Node();
  Paren.prototype.type = "Paren";
  Paren.prototype.genCSS = function (context, output) {
      output.add('(');
      this.value.genCSS(context, output);
      output.add(')');
  };
  Paren.prototype.eval = function (context) {
      return new Paren(this.value.eval(context));
  };
  module.exports = Paren;
  
  },{"./node":73}],76:[function(require,module,exports){
  var Node = require("./node"),
      Declaration = require("./declaration");
  
  var Property = function (name, index, currentFileInfo) {
      this.name = name;
      this._index = index;
      this._fileInfo = currentFileInfo;
  };
  Property.prototype = new Node();
  Property.prototype.type = "Property";
  Property.prototype.eval = function (context) {
      var property, name = this.name;
      // TODO: shorten this reference
      var mergeRules = context.pluginManager.less.visitors.ToCSSVisitor.prototype._mergeRules;
  
      if (this.evaluating) {
          throw { type: 'Name',
              message: "Recursive property reference for " + name,
              filename: this.fileInfo().filename,
              index: this.getIndex() };
      }
  
      this.evaluating = true;
  
      property = this.find(context.frames, function (frame) {
  
          var v, vArr = frame.property(name);
          if (vArr) {
              for (var i = 0; i < vArr.length; i++) {
                  v = vArr[i];
  
                  vArr[i] = new Declaration(v.name,
                      v.value,
                      v.important,
                      v.merge,
                      v.index,
                      v.currentFileInfo,
                      v.inline,
                      v.variable
                  );
              }
              mergeRules(vArr);
  
              v = vArr[vArr.length - 1];
              if (v.important) {
                  var importantScope = context.importantScope[context.importantScope.length - 1];
                  importantScope.important = v.important;
              }
              v = v.value.eval(context);
              return v;
          }
      });
      if (property) {
          this.evaluating = false;
          return property;
      } else {
          throw { type: 'Name',
              message: "Property '" + name + "' is undefined",
              filename: this.currentFileInfo.filename,
              index: this.index };
      }
  };
  Property.prototype.find = function (obj, fun) {
      for (var i = 0, r; i < obj.length; i++) {
          r = fun.call(obj, obj[i]);
          if (r) { return r; }
      }
      return null;
  };
  module.exports = Property;
  
  },{"./declaration":58,"./node":73}],77:[function(require,module,exports){
  var Node = require("./node"),
      Variable = require("./variable"),
      Property = require("./property");
  
  var Quoted = function (str, content, escaped, index, currentFileInfo) {
      this.escaped = (escaped == null) ? true : escaped;
      this.value = content || '';
      this.quote = str.charAt(0);
      this._index = index;
      this._fileInfo = currentFileInfo;
  };
  Quoted.prototype = new Node();
  Quoted.prototype.type = "Quoted";
  Quoted.prototype.genCSS = function (context, output) {
      if (!this.escaped) {
          output.add(this.quote, this.fileInfo(), this.getIndex());
      }
      output.add(this.value);
      if (!this.escaped) {
          output.add(this.quote);
      }
  };
  Quoted.prototype.containsVariables = function() {
      return this.value.match(/@\{([\w-]+)\}/);
  };
  Quoted.prototype.eval = function (context) {
      var that = this, value = this.value;
      var variableReplacement = function (_, name) {
          var v = new Variable('@' + name, that.getIndex(), that.fileInfo()).eval(context, true);
          return (v instanceof Quoted) ? v.value : v.toCSS();
      };
      var propertyReplacement = function (_, name) {
          var v = new Property('$' + name, that.getIndex(), that.fileInfo()).eval(context, true);
          return (v instanceof Quoted) ? v.value : v.toCSS();
      };
      function iterativeReplace(value, regexp, replacementFnc) {
          var evaluatedValue = value;
          do {
              value = evaluatedValue;
              evaluatedValue = value.replace(regexp, replacementFnc);
          } while (value !== evaluatedValue);
          return evaluatedValue;
      }
      value = iterativeReplace(value, /@\{([\w-]+)\}/g, variableReplacement);
      value = iterativeReplace(value, /\$\{([\w-]+)\}/g, propertyReplacement);
      return new Quoted(this.quote + value + this.quote, value, this.escaped, this.getIndex(), this.fileInfo());
  };
  Quoted.prototype.compare = function (other) {
      // when comparing quoted strings allow the quote to differ
      if (other.type === "Quoted" && !this.escaped && !other.escaped) {
          return Node.numericCompare(this.value, other.value);
      } else {
          return other.toCSS && this.toCSS() === other.toCSS() ? 0 : undefined;
      }
  };
  module.exports = Quoted;
  
  },{"./node":73,"./property":76,"./variable":85}],78:[function(require,module,exports){
  var Node = require("./node"),
      Declaration = require("./declaration"),
      Keyword = require("./keyword"),
      Comment = require("./comment"),
      Paren = require("./paren"),
      Selector = require("./selector"),
      Element = require("./element"),
      Anonymous = require("./anonymous"),
      contexts = require("../contexts"),
      globalFunctionRegistry = require("../functions/function-registry"),
      defaultFunc = require("../functions/default"),
      getDebugInfo = require("./debug-info"),
      utils = require("../utils");
  
  var Ruleset = function (selectors, rules, strictImports, visibilityInfo) {
      this.selectors = selectors;
      this.rules = rules;
      this._lookups = {};
      this._variables = null;
      this._properties = null;
      this.strictImports = strictImports;
      this.copyVisibilityInfo(visibilityInfo);
      this.allowRoot = true;
  
      this.setParent(this.selectors, this);
      this.setParent(this.rules, this);
  
  };
  Ruleset.prototype = new Node();
  Ruleset.prototype.type = "Ruleset";
  Ruleset.prototype.isRuleset = true;
  Ruleset.prototype.isRulesetLike = function() { return true; };
  Ruleset.prototype.accept = function (visitor) {
      if (this.paths) {
          this.paths = visitor.visitArray(this.paths, true);
      } else if (this.selectors) {
          this.selectors = visitor.visitArray(this.selectors);
      }
      if (this.rules && this.rules.length) {
          this.rules = visitor.visitArray(this.rules);
      }
  };
  Ruleset.prototype.eval = function (context) {
      var thisSelectors = this.selectors, selectors,
          selCnt, selector, i, hasOnePassingSelector = false;
  
      if (thisSelectors && (selCnt = thisSelectors.length)) {
          selectors = new Array(selCnt);
          defaultFunc.error({
              type: "Syntax",
              message: "it is currently only allowed in parametric mixin guards,"
          });
          for (i = 0; i < selCnt; i++) {
              selector = thisSelectors[i].eval(context);
              selectors[i] = selector;
              if (selector.evaldCondition) {
                  hasOnePassingSelector = true;
              }
          }
          defaultFunc.reset();
      } else {
          hasOnePassingSelector = true;
      }
  
      var rules = this.rules ? utils.copyArray(this.rules) : null,
          ruleset = new Ruleset(selectors, rules, this.strictImports, this.visibilityInfo()),
          rule, subRule;
  
      ruleset.originalRuleset = this;
      ruleset.root = this.root;
      ruleset.firstRoot = this.firstRoot;
      ruleset.allowImports = this.allowImports;
  
      if (this.debugInfo) {
          ruleset.debugInfo = this.debugInfo;
      }
  
      if (!hasOnePassingSelector) {
          rules.length = 0;
      }
  
      // inherit a function registry from the frames stack when possible;
      // otherwise from the global registry
      ruleset.functionRegistry = (function (frames) {
          var i = 0,
              n = frames.length,
              found;
          for ( ; i !== n ; ++i ) {
              found = frames[ i ].functionRegistry;
              if ( found ) { return found; }
          }
          return globalFunctionRegistry;
      }(context.frames)).inherit();
  
      // push the current ruleset to the frames stack
      var ctxFrames = context.frames;
      ctxFrames.unshift(ruleset);
  
      // currrent selectors
      var ctxSelectors = context.selectors;
      if (!ctxSelectors) {
          context.selectors = ctxSelectors = [];
      }
      ctxSelectors.unshift(this.selectors);
  
      // Evaluate imports
      if (ruleset.root || ruleset.allowImports || !ruleset.strictImports) {
          ruleset.evalImports(context);
      }
  
      // Store the frames around mixin definitions,
      // so they can be evaluated like closures when the time comes.
      var rsRules = ruleset.rules;
      for (i = 0; (rule = rsRules[i]); i++) {
          if (rule.evalFirst) {
              rsRules[i] = rule.eval(context);
          }
      }
  
      var mediaBlockCount = (context.mediaBlocks && context.mediaBlocks.length) || 0;
  
      // Evaluate mixin calls.
      for (i = 0; (rule = rsRules[i]); i++) {
          if (rule.type === "MixinCall") {
              /* jshint loopfunc:true */
              rules = rule.eval(context).filter(function(r) {
                  if ((r instanceof Declaration) && r.variable) {
                      // do not pollute the scope if the variable is
                      // already there. consider returning false here
                      // but we need a way to "return" variable from mixins
                      return !(ruleset.variable(r.name));
                  }
                  return true;
              });
              rsRules.splice.apply(rsRules, [i, 1].concat(rules));
              i += rules.length - 1;
              ruleset.resetCache();
          } else if (rule.type ===  "VariableCall") {
              /* jshint loopfunc:true */
              rules = rule.eval(context).rules.filter(function(r) {
                  if ((r instanceof Declaration) && r.variable) {
                      // do not pollute the scope at all
                      return false;
                  }
                  return true;
              });
              rsRules.splice.apply(rsRules, [i, 1].concat(rules));
              i += rules.length - 1;
              ruleset.resetCache();
          }
      }
  
      // Evaluate everything else
      for (i = 0; (rule = rsRules[i]); i++) {
          if (!rule.evalFirst) {
              rsRules[i] = rule = rule.eval ? rule.eval(context) : rule;
          }
      }
  
      // Evaluate everything else
      for (i = 0; (rule = rsRules[i]); i++) {
          // for rulesets, check if it is a css guard and can be removed
          if (rule instanceof Ruleset && rule.selectors && rule.selectors.length === 1) {
              // check if it can be folded in (e.g. & where)
              if (rule.selectors[0].isJustParentSelector()) {
                  rsRules.splice(i--, 1);
  
                  for (var j = 0; (subRule = rule.rules[j]); j++) {
                      if (subRule instanceof Node) {
                          subRule.copyVisibilityInfo(rule.visibilityInfo());
                          if (!(subRule instanceof Declaration) || !subRule.variable) {
                              rsRules.splice(++i, 0, subRule);
                          }
                      }
                  }
              }
          }
      }
  
      // Pop the stack
      ctxFrames.shift();
      ctxSelectors.shift();
  
      if (context.mediaBlocks) {
          for (i = mediaBlockCount; i < context.mediaBlocks.length; i++) {
              context.mediaBlocks[i].bubbleSelectors(selectors);
          }
      }
  
      return ruleset;
  };
  Ruleset.prototype.evalImports = function(context) {
      var rules = this.rules, i, importRules;
      if (!rules) { return; }
  
      for (i = 0; i < rules.length; i++) {
          if (rules[i].type === "Import") {
              importRules = rules[i].eval(context);
              if (importRules && (importRules.length || importRules.length === 0)) {
                  rules.splice.apply(rules, [i, 1].concat(importRules));
                  i += importRules.length - 1;
              } else {
                  rules.splice(i, 1, importRules);
              }
              this.resetCache();
          }
      }
  };
  Ruleset.prototype.makeImportant = function() {
      var result = new Ruleset(this.selectors, this.rules.map(function (r) {
          if (r.makeImportant) {
              return r.makeImportant();
          } else {
              return r;
          }
      }), this.strictImports, this.visibilityInfo());
  
      return result;
  };
  Ruleset.prototype.matchArgs = function (args) {
      return !args || args.length === 0;
  };
  // lets you call a css selector with a guard
  Ruleset.prototype.matchCondition = function (args, context) {
      var lastSelector = this.selectors[this.selectors.length - 1];
      if (!lastSelector.evaldCondition) {
          return false;
      }
      if (lastSelector.condition &&
          !lastSelector.condition.eval(
              new contexts.Eval(context,
                  context.frames))) {
          return false;
      }
      return true;
  };
  Ruleset.prototype.resetCache = function () {
      this._rulesets = null;
      this._variables = null;
      this._properties = null;
      this._lookups = {};
  };
  Ruleset.prototype.variables = function () {
      if (!this._variables) {
          this._variables = !this.rules ? {} : this.rules.reduce(function (hash, r) {
              if (r instanceof Declaration && r.variable === true) {
                  hash[r.name] = r;
              }
              // when evaluating variables in an import statement, imports have not been eval'd
              // so we need to go inside import statements.
              // guard against root being a string (in the case of inlined less)
              if (r.type === "Import" && r.root && r.root.variables) {
                  var vars = r.root.variables();
                  for (var name in vars) {
                      if (vars.hasOwnProperty(name)) {
                          hash[name] = vars[name];
                      }
                  }
              }
              return hash;
          }, {});
      }
      return this._variables;
  };
  Ruleset.prototype.properties = function () {
      if (!this._properties) {
          this._properties = !this.rules ? {} : this.rules.reduce(function (hash, r) {
              if (r instanceof Declaration && r.variable !== true) {
                  var name = (r.name.length === 1) && (r.name[0] instanceof Keyword) ?
                      r.name[0].value : r.name;
                  // Properties don't overwrite as they can merge
                  if (!hash['$' + name]) {
                      hash['$' + name] = [ r ];
                  }
                  else {
                      hash['$' + name].push(r);
                  }
              }
              return hash;
          }, {});
      }
      return this._properties;
  };
  Ruleset.prototype.variable = function (name) {
      var decl = this.variables()[name];
      if (decl) {
          return this.parseValue(decl);
      }
  };
  Ruleset.prototype.property = function (name) {
      var decl = this.properties()[name];
      if (decl) {
          return this.parseValue(decl);
      }
  };
  Ruleset.prototype.parseValue = function(toParse) {
      var self = this;
      function transformDeclaration(decl) {
          if (decl.value instanceof Anonymous && !decl.parsed) {
              this.parse.parseNode(
                  decl.value.value, 
                  ["value", "important"], 
                  decl.value.getIndex(), 
                  decl.fileInfo(), 
                  function(err, result) {
                      if (err) {
                          decl.parsed = true;
                      }
                      if (result) {
                          decl.value = result[0];
                          decl.important = result[1] || '';
                          decl.parsed = true;
                      }
                  });
  
              return decl;
          }
          else {
              return decl;
          }
      }
      if (!Array.isArray(toParse)) {
          return transformDeclaration.call(self, toParse);
      }
      else {
          var nodes = [];
          toParse.forEach(function(n) {
              nodes.push(transformDeclaration.call(self, n));
          });
          return nodes;
      }
  };
  Ruleset.prototype.rulesets = function () {
      if (!this.rules) { return []; }
  
      var filtRules = [], rules = this.rules,
          i, rule;
  
      for (i = 0; (rule = rules[i]); i++) {
          if (rule.isRuleset) {
              filtRules.push(rule);
          }
      }
  
      return filtRules;
  };
  Ruleset.prototype.prependRule = function (rule) {
      var rules = this.rules;
      if (rules) {
          rules.unshift(rule);
      } else {
          this.rules = [ rule ];
      }
      this.setParent(rule, this);
  };
  Ruleset.prototype.find = function (selector, self, filter) {
      self = self || this;
      var rules = [], match, foundMixins,
          key = selector.toCSS();
  
      if (key in this._lookups) { return this._lookups[key]; }
  
      this.rulesets().forEach(function (rule) {
          if (rule !== self) {
              for (var j = 0; j < rule.selectors.length; j++) {
                  match = selector.match(rule.selectors[j]);
                  if (match) {
                      if (selector.elements.length > match) {
                          if (!filter || filter(rule)) {
                              foundMixins = rule.find(new Selector(selector.elements.slice(match)), self, filter);
                              for (var i = 0; i < foundMixins.length; ++i) {
                                  foundMixins[i].path.push(rule);
                              }
                              Array.prototype.push.apply(rules, foundMixins);
                          }
                      } else {
                          rules.push({ rule: rule, path: []});
                      }
                      break;
                  }
              }
          }
      });
      this._lookups[key] = rules;
      return rules;
  };
  Ruleset.prototype.genCSS = function (context, output) {
      var i, j,
          charsetRuleNodes = [],
          ruleNodes = [],
          debugInfo,     // Line number debugging
          rule,
          path;
  
      context.tabLevel = (context.tabLevel || 0);
  
      if (!this.root) {
          context.tabLevel++;
      }
  
      var tabRuleStr = context.compress ? '' : Array(context.tabLevel + 1).join("  "),
          tabSetStr = context.compress ? '' : Array(context.tabLevel).join("  "),
          sep;
  
      var charsetNodeIndex = 0;
      var importNodeIndex = 0;
      for (i = 0; (rule = this.rules[i]); i++) {
          if (rule instanceof Comment) {
              if (importNodeIndex === i) {
                  importNodeIndex++;
              }
              ruleNodes.push(rule);
          } else if (rule.isCharset && rule.isCharset()) {
              ruleNodes.splice(charsetNodeIndex, 0, rule);
              charsetNodeIndex++;
              importNodeIndex++;
          } else if (rule.type === "Import") {
              ruleNodes.splice(importNodeIndex, 0, rule);
              importNodeIndex++;
          } else {
              ruleNodes.push(rule);
          }
      }
      ruleNodes = charsetRuleNodes.concat(ruleNodes);
  
      // If this is the root node, we don't render
      // a selector, or {}.
      if (!this.root) {
          debugInfo = getDebugInfo(context, this, tabSetStr);
  
          if (debugInfo) {
              output.add(debugInfo);
              output.add(tabSetStr);
          }
  
          var paths = this.paths, pathCnt = paths.length,
              pathSubCnt;
  
          sep = context.compress ? ',' : (',\n' + tabSetStr);
  
          for (i = 0; i < pathCnt; i++) {
              path = paths[i];
              if (!(pathSubCnt = path.length)) { continue; }
              if (i > 0) { output.add(sep); }
  
              context.firstSelector = true;
              path[0].genCSS(context, output);
  
              context.firstSelector = false;
              for (j = 1; j < pathSubCnt; j++) {
                  path[j].genCSS(context, output);
              }
          }
  
          output.add((context.compress ? '{' : ' {\n') + tabRuleStr);
      }
  
      // Compile rules and rulesets
      for (i = 0; (rule = ruleNodes[i]); i++) {
  
          if (i + 1 === ruleNodes.length) {
              context.lastRule = true;
          }
  
          var currentLastRule = context.lastRule;
          if (rule.isRulesetLike(rule)) {
              context.lastRule = false;
          }
  
          if (rule.genCSS) {
              rule.genCSS(context, output);
          } else if (rule.value) {
              output.add(rule.value.toString());
          }
  
          context.lastRule = currentLastRule;
  
          if (!context.lastRule && rule.isVisible()) {
              output.add(context.compress ? '' : ('\n' + tabRuleStr));
          } else {
              context.lastRule = false;
          }
      }
  
      if (!this.root) {
          output.add((context.compress ? '}' : '\n' + tabSetStr + '}'));
          context.tabLevel--;
      }
  
      if (!output.isEmpty() && !context.compress && this.firstRoot) {
          output.add('\n');
      }
  };
  
  Ruleset.prototype.joinSelectors = function (paths, context, selectors) {
      for (var s = 0; s < selectors.length; s++) {
          this.joinSelector(paths, context, selectors[s]);
      }
  };
  
  Ruleset.prototype.joinSelector = function (paths, context, selector) {
  
      function createParenthesis(elementsToPak, originalElement) {
          var replacementParen, j;
          if (elementsToPak.length === 0) {
              replacementParen = new Paren(elementsToPak[0]);
          } else {
              var insideParent = new Array(elementsToPak.length);
              for (j = 0; j < elementsToPak.length; j++) {
                  insideParent[j] = new Element(null, elementsToPak[j], originalElement._index, originalElement._fileInfo);
              }
              replacementParen = new Paren(new Selector(insideParent));
          }
          return replacementParen;
      }
  
      function createSelector(containedElement, originalElement) {
          var element, selector;
          element = new Element(null, containedElement, originalElement._index, originalElement._fileInfo);
          selector = new Selector([element]);
          return selector;
      }
  
      // joins selector path from `beginningPath` with selector path in `addPath`
      // `replacedElement` contains element that is being replaced by `addPath`
      // returns concatenated path
      function addReplacementIntoPath(beginningPath, addPath, replacedElement, originalSelector) {
          var newSelectorPath, lastSelector, newJoinedSelector;
          // our new selector path
          newSelectorPath = [];
  
          // construct the joined selector - if & is the first thing this will be empty,
          // if not newJoinedSelector will be the last set of elements in the selector
          if (beginningPath.length > 0) {
              newSelectorPath = utils.copyArray(beginningPath);
              lastSelector = newSelectorPath.pop();
              newJoinedSelector = originalSelector.createDerived(utils.copyArray(lastSelector.elements));
          }
          else {
              newJoinedSelector = originalSelector.createDerived([]);
          }
  
          if (addPath.length > 0) {
              // /deep/ is a combinator that is valid without anything in front of it
              // so if the & does not have a combinator that is "" or " " then
              // and there is a combinator on the parent, then grab that.
              // this also allows + a { & .b { .a & { ... though not sure why you would want to do that
              var combinator = replacedElement.combinator, parentEl = addPath[0].elements[0];
              if (combinator.emptyOrWhitespace && !parentEl.combinator.emptyOrWhitespace) {
                  combinator = parentEl.combinator;
              }
              // join the elements so far with the first part of the parent
              newJoinedSelector.elements.push(new Element(combinator, parentEl.value, replacedElement._index, replacedElement._fileInfo));
              newJoinedSelector.elements = newJoinedSelector.elements.concat(addPath[0].elements.slice(1));
          }
  
          // now add the joined selector - but only if it is not empty
          if (newJoinedSelector.elements.length !== 0) {
              newSelectorPath.push(newJoinedSelector);
          }
  
          // put together the parent selectors after the join (e.g. the rest of the parent)
          if (addPath.length > 1) {
              var restOfPath = addPath.slice(1);
              restOfPath = restOfPath.map(function (selector) {
                  return selector.createDerived(selector.elements, []);
              });
              newSelectorPath = newSelectorPath.concat(restOfPath);
          }
          return newSelectorPath;
      }
  
      // joins selector path from `beginningPath` with every selector path in `addPaths` array
      // `replacedElement` contains element that is being replaced by `addPath`
      // returns array with all concatenated paths
      function addAllReplacementsIntoPath( beginningPath, addPaths, replacedElement, originalSelector, result) {
          var j;
          for (j = 0; j < beginningPath.length; j++) {
              var newSelectorPath = addReplacementIntoPath(beginningPath[j], addPaths, replacedElement, originalSelector);
              result.push(newSelectorPath);
          }
          return result;
      }
  
      function mergeElementsOnToSelectors(elements, selectors) {
          var i, sel;
  
          if (elements.length === 0) {
              return ;
          }
          if (selectors.length === 0) {
              selectors.push([ new Selector(elements) ]);
              return;
          }
  
          for (i = 0; (sel = selectors[i]); i++) {
              // if the previous thing in sel is a parent this needs to join on to it
              if (sel.length > 0) {
                  sel[sel.length - 1] = sel[sel.length - 1].createDerived(sel[sel.length - 1].elements.concat(elements));
              }
              else {
                  sel.push(new Selector(elements));
              }
          }
      }
  
      // replace all parent selectors inside `inSelector` by content of `context` array
      // resulting selectors are returned inside `paths` array
      // returns true if `inSelector` contained at least one parent selector
      function replaceParentSelector(paths, context, inSelector) {
          // The paths are [[Selector]]
          // The first list is a list of comma separated selectors
          // The inner list is a list of inheritance separated selectors
          // e.g.
          // .a, .b {
          //   .c {
          //   }
          // }
          // == [[.a] [.c]] [[.b] [.c]]
          //
          var i, j, k, currentElements, newSelectors, selectorsMultiplied, sel, el, hadParentSelector = false, length, lastSelector;
          function findNestedSelector(element) {
              var maybeSelector;
              if (!(element.value instanceof Paren)) {
                  return null;
              }
  
              maybeSelector = element.value.value;
              if (!(maybeSelector instanceof Selector)) {
                  return null;
              }
  
              return maybeSelector;
          }
  
          // the elements from the current selector so far
          currentElements = [];
          // the current list of new selectors to add to the path.
          // We will build it up. We initiate it with one empty selector as we "multiply" the new selectors
          // by the parents
          newSelectors = [
              []
          ];
  
          for (i = 0; (el = inSelector.elements[i]); i++) {
              // non parent reference elements just get added
              if (el.value !== "&") {
                  var nestedSelector = findNestedSelector(el);
                  if (nestedSelector != null) {
                      // merge the current list of non parent selector elements
                      // on to the current list of selectors to add
                      mergeElementsOnToSelectors(currentElements, newSelectors);
  
                      var nestedPaths = [], replaced, replacedNewSelectors = [];
                      replaced = replaceParentSelector(nestedPaths, context, nestedSelector);
                      hadParentSelector = hadParentSelector || replaced;
                      // the nestedPaths array should have only one member - replaceParentSelector does not multiply selectors
                      for (k = 0; k < nestedPaths.length; k++) {
                          var replacementSelector = createSelector(createParenthesis(nestedPaths[k], el), el);
                          addAllReplacementsIntoPath(newSelectors, [replacementSelector], el, inSelector, replacedNewSelectors);
                      }
                      newSelectors = replacedNewSelectors;
                      currentElements = [];
  
                  } else {
                      currentElements.push(el);
                  }
  
              } else {
                  hadParentSelector = true;
                  // the new list of selectors to add
                  selectorsMultiplied = [];
  
                  // merge the current list of non parent selector elements
                  // on to the current list of selectors to add
                  mergeElementsOnToSelectors(currentElements, newSelectors);
  
                  // loop through our current selectors
                  for (j = 0; j < newSelectors.length; j++) {
                      sel = newSelectors[j];
                      // if we don't have any parent paths, the & might be in a mixin so that it can be used
                      // whether there are parents or not
                      if (context.length === 0) {
                          // the combinator used on el should now be applied to the next element instead so that
                          // it is not lost
                          if (sel.length > 0) {
                              sel[0].elements.push(new Element(el.combinator, '', el._index, el._fileInfo));
                          }
                          selectorsMultiplied.push(sel);
                      }
                      else {
                          // and the parent selectors
                          for (k = 0; k < context.length; k++) {
                              // We need to put the current selectors
                              // then join the last selector's elements on to the parents selectors
                              var newSelectorPath = addReplacementIntoPath(sel, context[k], el, inSelector);
                              // add that to our new set of selectors
                              selectorsMultiplied.push(newSelectorPath);
                          }
                      }
                  }
  
                  // our new selectors has been multiplied, so reset the state
                  newSelectors = selectorsMultiplied;
                  currentElements = [];
              }
          }
  
          // if we have any elements left over (e.g. .a& .b == .b)
          // add them on to all the current selectors
          mergeElementsOnToSelectors(currentElements, newSelectors);
  
          for (i = 0; i < newSelectors.length; i++) {
              length = newSelectors[i].length;
              if (length > 0) {
                  paths.push(newSelectors[i]);
                  lastSelector = newSelectors[i][length - 1];
                  newSelectors[i][length - 1] = lastSelector.createDerived(lastSelector.elements, inSelector.extendList);
              }
          }
  
          return hadParentSelector;
      }
  
      function deriveSelector(visibilityInfo, deriveFrom) {
          var newSelector = deriveFrom.createDerived(deriveFrom.elements, deriveFrom.extendList, deriveFrom.evaldCondition);
          newSelector.copyVisibilityInfo(visibilityInfo);
          return newSelector;
      }
  
      // joinSelector code follows
      var i, newPaths, hadParentSelector;
  
      newPaths = [];
      hadParentSelector = replaceParentSelector(newPaths, context, selector);
  
      if (!hadParentSelector) {
          if (context.length > 0) {
              newPaths = [];
              for (i = 0; i < context.length; i++) {
  
                  var concatenated = context[i].map(deriveSelector.bind(this, selector.visibilityInfo()));
  
                  concatenated.push(selector);
                  newPaths.push(concatenated);
              }
          }
          else {
              newPaths = [[selector]];
          }
      }
  
      for (i = 0; i < newPaths.length; i++) {
          paths.push(newPaths[i]);
      }
  
  };
  module.exports = Ruleset;
  
  },{"../contexts":12,"../functions/default":24,"../functions/function-registry":26,"../utils":86,"./anonymous":48,"./comment":55,"./debug-info":57,"./declaration":58,"./element":61,"./keyword":68,"./node":73,"./paren":75,"./selector":79}],79:[function(require,module,exports){
  var Node = require("./node"),
      Element = require("./element"),
      LessError = require("../less-error");
  
  var Selector = function (elements, extendList, condition, index, currentFileInfo, visibilityInfo) {
      this.extendList = extendList;
      this.condition = condition;
      this.evaldCondition = !condition;
      this._index = index;
      this._fileInfo = currentFileInfo;
      this.elements = this.getElements(elements);
      this.mixinElements_ = undefined;
      this.copyVisibilityInfo(visibilityInfo);
      this.setParent(this.elements, this);
  };
  Selector.prototype = new Node();
  Selector.prototype.type = "Selector";
  Selector.prototype.accept = function (visitor) {
      if (this.elements) {
          this.elements = visitor.visitArray(this.elements);
      }
      if (this.extendList) {
          this.extendList = visitor.visitArray(this.extendList);
      }
      if (this.condition) {
          this.condition = visitor.visit(this.condition);
      }
  };
  Selector.prototype.createDerived = function(elements, extendList, evaldCondition) {
      elements = this.getElements(elements);
      var newSelector = new Selector(elements, extendList || this.extendList,
          null, this.getIndex(), this.fileInfo(), this.visibilityInfo());
      newSelector.evaldCondition = (evaldCondition != null) ? evaldCondition : this.evaldCondition;
      newSelector.mediaEmpty = this.mediaEmpty;
      return newSelector;
  };
  Selector.prototype.getElements = function(els) {
      if (typeof els === "string") {
          this.parse.parseNode(
              els, 
              ["selector"],
              this._index, 
              this._fileInfo, 
              function(err, result) {
                  if (err) {
                      throw new LessError({
                          index: err.index,
                          message: err.message
                      }, this.parse.imports, this._fileInfo.filename);
                  }
                  els = result[0].elements;
              });
      }
      return els;
  };
  Selector.prototype.createEmptySelectors = function() {
      var el = new Element('', '&', this._index, this._fileInfo),
          sels = [new Selector([el], null, null, this._index, this._fileInfo)];
      sels[0].mediaEmpty = true;
      return sels;
  };
  Selector.prototype.match = function (other) {
      var elements = this.elements,
          len = elements.length,
          olen, i;
  
      other = other.mixinElements();
      olen = other.length;
      if (olen === 0 || len < olen) {
          return 0;
      } else {
          for (i = 0; i < olen; i++) {
              if (elements[i].value !== other[i]) {
                  return 0;
              }
          }
      }
  
      return olen; // return number of matched elements
  };
  Selector.prototype.mixinElements = function() {
      if (this.mixinElements_) {
          return this.mixinElements_;
      }
  
      var elements = this.elements.map( function(v) {
          return v.combinator.value + (v.value.value || v.value);
      }).join("").match(/[,&#\*\.\w-]([\w-]|(\\.))*/g);
  
      if (elements) {
          if (elements[0] === "&") {
              elements.shift();
          }
      } else {
          elements = [];
      }
  
      return (this.mixinElements_ = elements);
  };
  Selector.prototype.isJustParentSelector = function() {
      return !this.mediaEmpty &&
          this.elements.length === 1 &&
          this.elements[0].value === '&' &&
          (this.elements[0].combinator.value === ' ' || this.elements[0].combinator.value === '');
  };
  Selector.prototype.eval = function (context) {
      var evaldCondition = this.condition && this.condition.eval(context),
          elements = this.elements, extendList = this.extendList;
  
      elements = elements && elements.map(function (e) { return e.eval(context); });
      extendList = extendList && extendList.map(function(extend) { return extend.eval(context); });
  
      return this.createDerived(elements, extendList, evaldCondition);
  };
  Selector.prototype.genCSS = function (context, output) {
      var i, element;
      if ((!context || !context.firstSelector) && this.elements[0].combinator.value === "") {
          output.add(' ', this.fileInfo(), this.getIndex());
      }
      for (i = 0; i < this.elements.length; i++) {
          element = this.elements[i];
          element.genCSS(context, output);
      }
  };
  Selector.prototype.getIsOutput = function() {
      return this.evaldCondition;
  };
  module.exports = Selector;
  
  },{"../less-error":36,"./element":61,"./node":73}],80:[function(require,module,exports){
  var Node = require("./node");
  
  var UnicodeDescriptor = function (value) {
      this.value = value;
  };
  UnicodeDescriptor.prototype = new Node();
  UnicodeDescriptor.prototype.type = "UnicodeDescriptor";
  
  module.exports = UnicodeDescriptor;
  
  },{"./node":73}],81:[function(require,module,exports){
  var Node = require("./node"),
      unitConversions = require("../data/unit-conversions"),
      utils = require("../utils");
  
  var Unit = function (numerator, denominator, backupUnit) {
      this.numerator = numerator ? utils.copyArray(numerator).sort() : [];
      this.denominator = denominator ? utils.copyArray(denominator).sort() : [];
      if (backupUnit) {
          this.backupUnit = backupUnit;
      } else if (numerator && numerator.length) {
          this.backupUnit = numerator[0];
      }
  };
  
  Unit.prototype = new Node();
  Unit.prototype.type = "Unit";
  Unit.prototype.clone = function () {
      return new Unit(utils.copyArray(this.numerator), utils.copyArray(this.denominator), this.backupUnit);
  };
  Unit.prototype.genCSS = function (context, output) {
      // Dimension checks the unit is singular and throws an error if in strict math mode.
      var strictUnits = context && context.strictUnits;
      if (this.numerator.length === 1) {
          output.add(this.numerator[0]); // the ideal situation
      } else if (!strictUnits && this.backupUnit) {
          output.add(this.backupUnit);
      } else if (!strictUnits && this.denominator.length) {
          output.add(this.denominator[0]);
      }
  };
  Unit.prototype.toString = function () {
      var i, returnStr = this.numerator.join("*");
      for (i = 0; i < this.denominator.length; i++) {
          returnStr += "/" + this.denominator[i];
      }
      return returnStr;
  };
  Unit.prototype.compare = function (other) {
      return this.is(other.toString()) ? 0 : undefined;
  };
  Unit.prototype.is = function (unitString) {
      return this.toString().toUpperCase() === unitString.toUpperCase();
  };
  Unit.prototype.isLength = function () {
      return Boolean(this.toCSS().match(/px|em|%|in|cm|mm|pc|pt|ex/));
  };
  Unit.prototype.isEmpty = function () {
      return this.numerator.length === 0 && this.denominator.length === 0;
  };
  Unit.prototype.isSingular = function() {
      return this.numerator.length <= 1 && this.denominator.length === 0;
  };
  Unit.prototype.map = function(callback) {
      var i;
  
      for (i = 0; i < this.numerator.length; i++) {
          this.numerator[i] = callback(this.numerator[i], false);
      }
  
      for (i = 0; i < this.denominator.length; i++) {
          this.denominator[i] = callback(this.denominator[i], true);
      }
  };
  Unit.prototype.usedUnits = function() {
      var group, result = {}, mapUnit, groupName;
  
      mapUnit = function (atomicUnit) {
          /* jshint loopfunc:true */
          if (group.hasOwnProperty(atomicUnit) && !result[groupName]) {
              result[groupName] = atomicUnit;
          }
  
          return atomicUnit;
      };
  
      for (groupName in unitConversions) {
          if (unitConversions.hasOwnProperty(groupName)) {
              group = unitConversions[groupName];
  
              this.map(mapUnit);
          }
      }
  
      return result;
  };
  Unit.prototype.cancel = function () {
      var counter = {}, atomicUnit, i;
  
      for (i = 0; i < this.numerator.length; i++) {
          atomicUnit = this.numerator[i];
          counter[atomicUnit] = (counter[atomicUnit] || 0) + 1;
      }
  
      for (i = 0; i < this.denominator.length; i++) {
          atomicUnit = this.denominator[i];
          counter[atomicUnit] = (counter[atomicUnit] || 0) - 1;
      }
  
      this.numerator = [];
      this.denominator = [];
  
      for (atomicUnit in counter) {
          if (counter.hasOwnProperty(atomicUnit)) {
              var count = counter[atomicUnit];
  
              if (count > 0) {
                  for (i = 0; i < count; i++) {
                      this.numerator.push(atomicUnit);
                  }
              } else if (count < 0) {
                  for (i = 0; i < -count; i++) {
                      this.denominator.push(atomicUnit);
                  }
              }
          }
      }
  
      this.numerator.sort();
      this.denominator.sort();
  };
  module.exports = Unit;
  
  },{"../data/unit-conversions":15,"../utils":86,"./node":73}],82:[function(require,module,exports){
  var Node = require("./node");
  
  var URL = function (val, index, currentFileInfo, isEvald) {
      this.value = val;
      this._index = index;
      this._fileInfo = currentFileInfo;
      this.isEvald = isEvald;
  };
  URL.prototype = new Node();
  URL.prototype.type = "Url";
  URL.prototype.accept = function (visitor) {
      this.value = visitor.visit(this.value);
  };
  URL.prototype.genCSS = function (context, output) {
      output.add("url(");
      this.value.genCSS(context, output);
      output.add(")");
  };
  URL.prototype.eval = function (context) {
      var val = this.value.eval(context),
          rootpath;
  
      if (!this.isEvald) {
          // Add the base path if the URL is relative
          rootpath = this.fileInfo() && this.fileInfo().rootpath;
          if (rootpath &&
              typeof val.value === "string" &&
              context.isPathRelative(val.value)) {
  
              if (!val.quote) {
                  rootpath = rootpath.replace(/[\(\)'"\s]/g, function(match) { return "\\" + match; });
              }
              val.value = rootpath + val.value;
          }
  
          val.value = context.normalizePath(val.value);
  
          // Add url args if enabled
          if (context.urlArgs) {
              if (!val.value.match(/^\s*data:/)) {
                  var delimiter = val.value.indexOf('?') === -1 ? '?' : '&';
                  var urlArgs = delimiter + context.urlArgs;
                  if (val.value.indexOf('#') !== -1) {
                      val.value = val.value.replace('#', urlArgs + '#');
                  } else {
                      val.value += urlArgs;
                  }
              }
          }
      }
  
      return new URL(val, this.getIndex(), this.fileInfo(), true);
  };
  module.exports = URL;
  
  },{"./node":73}],83:[function(require,module,exports){
  var Node = require("./node");
  
  var Value = function (value) {
      if (!value) {
          throw new Error("Value requires an array argument");
      }
      if (!Array.isArray(value)) {
          this.value = [ value ];
      }
      else {
          this.value = value;
      }
  };
  Value.prototype = new Node();
  Value.prototype.type = "Value";
  Value.prototype.accept = function (visitor) {
      if (this.value) {
          this.value = visitor.visitArray(this.value);
      }
  };
  Value.prototype.eval = function (context) {
      if (this.value.length === 1) {
          return this.value[0].eval(context);
      } else {
          return new Value(this.value.map(function (v) {
              return v.eval(context);
          }));
      }
  };
  Value.prototype.genCSS = function (context, output) {
      var i;
      for (i = 0; i < this.value.length; i++) {
          this.value[i].genCSS(context, output);
          if (i + 1 < this.value.length) {
              output.add((context && context.compress) ? ',' : ', ');
          }
      }
  };
  module.exports = Value;
  
  },{"./node":73}],84:[function(require,module,exports){
  var Node = require("./node"),
      Variable = require("./variable");
  
  var VariableCall = function (variable) {
      this.variable = variable;
      this.allowRoot = true;
  };
  VariableCall.prototype = new Node();
  VariableCall.prototype.type = "VariableCall";
  VariableCall.prototype.eval = function (context) {
      var detachedRuleset = new Variable(this.variable).eval(context);
      return detachedRuleset.callEval(context);
  };
  module.exports = VariableCall;
  
  },{"./node":73,"./variable":85}],85:[function(require,module,exports){
  var Node = require("./node");
  
  var Variable = function (name, index, currentFileInfo) {
      this.name = name;
      this._index = index;
      this._fileInfo = currentFileInfo;
  };
  Variable.prototype = new Node();
  Variable.prototype.type = "Variable";
  Variable.prototype.eval = function (context) {
      var variable, name = this.name;
  
      if (name.indexOf('@@') === 0) {
          name = '@' + new Variable(name.slice(1), this.getIndex(), this.fileInfo()).eval(context).value;
      }
  
      if (this.evaluating) {
          throw { type: 'Name',
              message: "Recursive variable definition for " + name,
              filename: this.fileInfo().filename,
              index: this.getIndex() };
      }
  
      this.evaluating = true;
  
      variable = this.find(context.frames, function (frame) {
          var v = frame.variable(name);
          if (v) {
              if (v.important) {
                  var importantScope = context.importantScope[context.importantScope.length - 1];
                  importantScope.important = v.important;
              }
              return v.value.eval(context);
          }
      });
      if (variable) {
          this.evaluating = false;
          return variable;
      } else {
          throw { type: 'Name',
              message: "variable " + name + " is undefined",
              filename: this.fileInfo().filename,
              index: this.getIndex() };
      }
  };
  Variable.prototype.find = function (obj, fun) {
      for (var i = 0, r; i < obj.length; i++) {
          r = fun.call(obj, obj[i]);
          if (r) { return r; }
      }
      return null;
  };
  module.exports = Variable;
  
  },{"./node":73}],86:[function(require,module,exports){
  /* jshint proto: true */
  module.exports = {
      getLocation: function(index, inputStream) {
          var n = index + 1,
              line = null,
              column = -1;
  
          while (--n >= 0 && inputStream.charAt(n) !== '\n') {
              column++;
          }
  
          if (typeof index === 'number') {
              line = (inputStream.slice(0, index).match(/\n/g) || "").length;
          }
  
          return {
              line: line,
              column: column
          };
      },
      copyArray: function(arr) {
          var i, length = arr.length,
              copy = new Array(length);
          
          for (i = 0; i < length; i++) {
              copy[i] = arr[i];
          }
          return copy;
      },
      clone: function (obj) {
          var cloned = {};
          for (var prop in obj) {
              if (obj.hasOwnProperty(prop)) {
                  cloned[prop] = obj[prop];
              }
          }
          return cloned;
      },
      defaults: function(obj1, obj2) {
          if (!obj2._defaults || obj2._defaults !== obj1) {
              for (var prop in obj1) {
                  if (obj1.hasOwnProperty(prop)) {
                      if (!obj2.hasOwnProperty(prop)) {
                          obj2[prop] = obj1[prop];
                      }
                      else if (Array.isArray(obj1[prop])
                          && Array.isArray(obj2[prop])) {
  
                          obj1[prop].forEach(function(p) {
                              if (obj2[prop].indexOf(p) === -1) {
                                  obj2[prop].push(p);
                              }
                          });
                      }
                  }
              }
          }
          obj2._defaults = obj1;
          return obj2;
      },
      merge: function(obj1, obj2) {
          for (var prop in obj2) {
              if (obj2.hasOwnProperty(prop)) {
                  obj1[prop] = obj2[prop];
              }
          }
          return obj1;
      }
  };
  
  },{}],87:[function(require,module,exports){
  var tree = require("../tree"),
      Visitor = require("./visitor"),
      logger = require("../logger"),
      utils = require("../utils");
  
  /* jshint loopfunc:true */
  
  var ExtendFinderVisitor = function() {
      this._visitor = new Visitor(this);
      this.contexts = [];
      this.allExtendsStack = [[]];
  };
  
  ExtendFinderVisitor.prototype = {
      run: function (root) {
          root = this._visitor.visit(root);
          root.allExtends = this.allExtendsStack[0];
          return root;
      },
      visitDeclaration: function (declNode, visitArgs) {
          visitArgs.visitDeeper = false;
      },
      visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
          visitArgs.visitDeeper = false;
      },
      visitRuleset: function (rulesetNode, visitArgs) {
          if (rulesetNode.root) {
              return;
          }
  
          var i, j, extend, allSelectorsExtendList = [], extendList;
  
          // get &:extend(.a); rules which apply to all selectors in this ruleset
          var rules = rulesetNode.rules, ruleCnt = rules ? rules.length : 0;
          for (i = 0; i < ruleCnt; i++) {
              if (rulesetNode.rules[i] instanceof tree.Extend) {
                  allSelectorsExtendList.push(rules[i]);
                  rulesetNode.extendOnEveryPath = true;
              }
          }
  
          // now find every selector and apply the extends that apply to all extends
          // and the ones which apply to an individual extend
          var paths = rulesetNode.paths;
          for (i = 0; i < paths.length; i++) {
              var selectorPath = paths[i],
                  selector = selectorPath[selectorPath.length - 1],
                  selExtendList = selector.extendList;
  
              extendList = selExtendList ? utils.copyArray(selExtendList).concat(allSelectorsExtendList)
                                         : allSelectorsExtendList;
  
              if (extendList) {
                  extendList = extendList.map(function(allSelectorsExtend) {
                      return allSelectorsExtend.clone();
                  });
              }
  
              for (j = 0; j < extendList.length; j++) {
                  this.foundExtends = true;
                  extend = extendList[j];
                  extend.findSelfSelectors(selectorPath);
                  extend.ruleset = rulesetNode;
                  if (j === 0) { extend.firstExtendOnThisSelectorPath = true; }
                  this.allExtendsStack[this.allExtendsStack.length - 1].push(extend);
              }
          }
  
          this.contexts.push(rulesetNode.selectors);
      },
      visitRulesetOut: function (rulesetNode) {
          if (!rulesetNode.root) {
              this.contexts.length = this.contexts.length - 1;
          }
      },
      visitMedia: function (mediaNode, visitArgs) {
          mediaNode.allExtends = [];
          this.allExtendsStack.push(mediaNode.allExtends);
      },
      visitMediaOut: function (mediaNode) {
          this.allExtendsStack.length = this.allExtendsStack.length - 1;
      },
      visitAtRule: function (atRuleNode, visitArgs) {
          atRuleNode.allExtends = [];
          this.allExtendsStack.push(atRuleNode.allExtends);
      },
      visitAtRuleOut: function (atRuleNode) {
          this.allExtendsStack.length = this.allExtendsStack.length - 1;
      }
  };
  
  var ProcessExtendsVisitor = function() {
      this._visitor = new Visitor(this);
  };
  
  ProcessExtendsVisitor.prototype = {
      run: function(root) {
          var extendFinder = new ExtendFinderVisitor();
          this.extendIndices = {};
          extendFinder.run(root);
          if (!extendFinder.foundExtends) { return root; }
          root.allExtends = root.allExtends.concat(this.doExtendChaining(root.allExtends, root.allExtends));
          this.allExtendsStack = [root.allExtends];
          var newRoot = this._visitor.visit(root);
          this.checkExtendsForNonMatched(root.allExtends);
          return newRoot;
      },
      checkExtendsForNonMatched: function(extendList) {
          var indices = this.extendIndices;
          extendList.filter(function(extend) {
              return !extend.hasFoundMatches && extend.parent_ids.length == 1;
          }).forEach(function(extend) {
              var selector = "_unknown_";
              try {
                  selector = extend.selector.toCSS({});
              }
              catch (_) {}
  
              if (!indices[extend.index + ' ' + selector]) {
                  indices[extend.index + ' ' + selector] = true;
                  logger.warn("extend '" + selector + "' has no matches");
              }
          });
      },
      doExtendChaining: function (extendsList, extendsListTarget, iterationCount) {
          //
          // chaining is different from normal extension.. if we extend an extend then we are not just copying, altering
          // and pasting the selector we would do normally, but we are also adding an extend with the same target selector
          // this means this new extend can then go and alter other extends
          //
          // this method deals with all the chaining work - without it, extend is flat and doesn't work on other extend selectors
          // this is also the most expensive.. and a match on one selector can cause an extension of a selector we had already
          // processed if we look at each selector at a time, as is done in visitRuleset
  
          var extendIndex, targetExtendIndex, matches, extendsToAdd = [], newSelector, extendVisitor = this, selectorPath,
              extend, targetExtend, newExtend;
  
          iterationCount = iterationCount || 0;
  
          // loop through comparing every extend with every target extend.
          // a target extend is the one on the ruleset we are looking at copy/edit/pasting in place
          // e.g.  .a:extend(.b) {}  and .b:extend(.c) {} then the first extend extends the second one
          // and the second is the target.
          // the separation into two lists allows us to process a subset of chains with a bigger set, as is the
          // case when processing media queries
          for (extendIndex = 0; extendIndex < extendsList.length; extendIndex++) {
              for (targetExtendIndex = 0; targetExtendIndex < extendsListTarget.length; targetExtendIndex++) {
  
                  extend = extendsList[extendIndex];
                  targetExtend = extendsListTarget[targetExtendIndex];
  
                  // look for circular references
                  if ( extend.parent_ids.indexOf( targetExtend.object_id ) >= 0 ) { continue; }
  
                  // find a match in the target extends self selector (the bit before :extend)
                  selectorPath = [targetExtend.selfSelectors[0]];
                  matches = extendVisitor.findMatch(extend, selectorPath);
  
                  if (matches.length) {
                      extend.hasFoundMatches = true;
  
                      // we found a match, so for each self selector..
                      extend.selfSelectors.forEach(function(selfSelector) {
                          var info = targetExtend.visibilityInfo();
  
                          // process the extend as usual
                          newSelector = extendVisitor.extendSelector(matches, selectorPath, selfSelector, extend.isVisible());
  
                          // but now we create a new extend from it
                          newExtend = new(tree.Extend)(targetExtend.selector, targetExtend.option, 0, targetExtend.fileInfo(), info);
                          newExtend.selfSelectors = newSelector;
  
                          // add the extend onto the list of extends for that selector
                          newSelector[newSelector.length - 1].extendList = [newExtend];
  
                          // record that we need to add it.
                          extendsToAdd.push(newExtend);
                          newExtend.ruleset = targetExtend.ruleset;
  
                          //remember its parents for circular references
                          newExtend.parent_ids = newExtend.parent_ids.concat(targetExtend.parent_ids, extend.parent_ids);
  
                          // only process the selector once.. if we have :extend(.a,.b) then multiple
                          // extends will look at the same selector path, so when extending
                          // we know that any others will be duplicates in terms of what is added to the css
                          if (targetExtend.firstExtendOnThisSelectorPath) {
                              newExtend.firstExtendOnThisSelectorPath = true;
                              targetExtend.ruleset.paths.push(newSelector);
                          }
                      });
                  }
              }
          }
  
          if (extendsToAdd.length) {
              // try to detect circular references to stop a stack overflow.
              // may no longer be needed.
              this.extendChainCount++;
              if (iterationCount > 100) {
                  var selectorOne = "{unable to calculate}";
                  var selectorTwo = "{unable to calculate}";
                  try {
                      selectorOne = extendsToAdd[0].selfSelectors[0].toCSS();
                      selectorTwo = extendsToAdd[0].selector.toCSS();
                  }
                  catch (e) {}
                  throw { message: "extend circular reference detected. One of the circular extends is currently:" +
                      selectorOne + ":extend(" + selectorTwo + ")"};
              }
  
              // now process the new extends on the existing rules so that we can handle a extending b extending c extending
              // d extending e...
              return extendsToAdd.concat(extendVisitor.doExtendChaining(extendsToAdd, extendsListTarget, iterationCount + 1));
          } else {
              return extendsToAdd;
          }
      },
      visitDeclaration: function (ruleNode, visitArgs) {
          visitArgs.visitDeeper = false;
      },
      visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
          visitArgs.visitDeeper = false;
      },
      visitSelector: function (selectorNode, visitArgs) {
          visitArgs.visitDeeper = false;
      },
      visitRuleset: function (rulesetNode, visitArgs) {
          if (rulesetNode.root) {
              return;
          }
          var matches, pathIndex, extendIndex, allExtends = this.allExtendsStack[this.allExtendsStack.length - 1],
              selectorsToAdd = [], extendVisitor = this, selectorPath;
  
          // look at each selector path in the ruleset, find any extend matches and then copy, find and replace
  
          for (extendIndex = 0; extendIndex < allExtends.length; extendIndex++) {
              for (pathIndex = 0; pathIndex < rulesetNode.paths.length; pathIndex++) {
                  selectorPath = rulesetNode.paths[pathIndex];
  
                  // extending extends happens initially, before the main pass
                  if (rulesetNode.extendOnEveryPath) { continue; }
                  var extendList = selectorPath[selectorPath.length - 1].extendList;
                  if (extendList && extendList.length) { continue; }
  
                  matches = this.findMatch(allExtends[extendIndex], selectorPath);
  
                  if (matches.length) {
                      allExtends[extendIndex].hasFoundMatches = true;
  
                      allExtends[extendIndex].selfSelectors.forEach(function(selfSelector) {
                          var extendedSelectors;
                          extendedSelectors = extendVisitor.extendSelector(matches, selectorPath, selfSelector, allExtends[extendIndex].isVisible());
                          selectorsToAdd.push(extendedSelectors);
                      });
                  }
              }
          }
          rulesetNode.paths = rulesetNode.paths.concat(selectorsToAdd);
      },
      findMatch: function (extend, haystackSelectorPath) {
          //
          // look through the haystack selector path to try and find the needle - extend.selector
          // returns an array of selector matches that can then be replaced
          //
          var haystackSelectorIndex, hackstackSelector, hackstackElementIndex, haystackElement,
              targetCombinator, i,
              extendVisitor = this,
              needleElements = extend.selector.elements,
              potentialMatches = [], potentialMatch, matches = [];
  
          // loop through the haystack elements
          for (haystackSelectorIndex = 0; haystackSelectorIndex < haystackSelectorPath.length; haystackSelectorIndex++) {
              hackstackSelector = haystackSelectorPath[haystackSelectorIndex];
  
              for (hackstackElementIndex = 0; hackstackElementIndex < hackstackSelector.elements.length; hackstackElementIndex++) {
  
                  haystackElement = hackstackSelector.elements[hackstackElementIndex];
  
                  // if we allow elements before our match we can add a potential match every time. otherwise only at the first element.
                  if (extend.allowBefore || (haystackSelectorIndex === 0 && hackstackElementIndex === 0)) {
                      potentialMatches.push({pathIndex: haystackSelectorIndex, index: hackstackElementIndex, matched: 0,
                          initialCombinator: haystackElement.combinator});
                  }
  
                  for (i = 0; i < potentialMatches.length; i++) {
                      potentialMatch = potentialMatches[i];
  
                      // selectors add " " onto the first element. When we use & it joins the selectors together, but if we don't
                      // then each selector in haystackSelectorPath has a space before it added in the toCSS phase. so we need to
                      // work out what the resulting combinator will be
                      targetCombinator = haystackElement.combinator.value;
                      if (targetCombinator === '' && hackstackElementIndex === 0) {
                          targetCombinator = ' ';
                      }
  
                      // if we don't match, null our match to indicate failure
                      if (!extendVisitor.isElementValuesEqual(needleElements[potentialMatch.matched].value, haystackElement.value) ||
                          (potentialMatch.matched > 0 && needleElements[potentialMatch.matched].combinator.value !== targetCombinator)) {
                          potentialMatch = null;
                      } else {
                          potentialMatch.matched++;
                      }
  
                      // if we are still valid and have finished, test whether we have elements after and whether these are allowed
                      if (potentialMatch) {
                          potentialMatch.finished = potentialMatch.matched === needleElements.length;
                          if (potentialMatch.finished &&
                              (!extend.allowAfter &&
                                  (hackstackElementIndex + 1 < hackstackSelector.elements.length || haystackSelectorIndex + 1 < haystackSelectorPath.length))) {
                              potentialMatch = null;
                          }
                      }
                      // if null we remove, if not, we are still valid, so either push as a valid match or continue
                      if (potentialMatch) {
                          if (potentialMatch.finished) {
                              potentialMatch.length = needleElements.length;
                              potentialMatch.endPathIndex = haystackSelectorIndex;
                              potentialMatch.endPathElementIndex = hackstackElementIndex + 1; // index after end of match
                              potentialMatches.length = 0; // we don't allow matches to overlap, so start matching again
                              matches.push(potentialMatch);
                          }
                      } else {
                          potentialMatches.splice(i, 1);
                          i--;
                      }
                  }
              }
          }
          return matches;
      },
      isElementValuesEqual: function(elementValue1, elementValue2) {
          if (typeof elementValue1 === "string" || typeof elementValue2 === "string") {
              return elementValue1 === elementValue2;
          }
          if (elementValue1 instanceof tree.Attribute) {
              if (elementValue1.op !== elementValue2.op || elementValue1.key !== elementValue2.key) {
                  return false;
              }
              if (!elementValue1.value || !elementValue2.value) {
                  if (elementValue1.value || elementValue2.value) {
                      return false;
                  }
                  return true;
              }
              elementValue1 = elementValue1.value.value || elementValue1.value;
              elementValue2 = elementValue2.value.value || elementValue2.value;
              return elementValue1 === elementValue2;
          }
          elementValue1 = elementValue1.value;
          elementValue2 = elementValue2.value;
          if (elementValue1 instanceof tree.Selector) {
              if (!(elementValue2 instanceof tree.Selector) || elementValue1.elements.length !== elementValue2.elements.length) {
                  return false;
              }
              for (var i = 0; i  < elementValue1.elements.length; i++) {
                  if (elementValue1.elements[i].combinator.value !== elementValue2.elements[i].combinator.value) {
                      if (i !== 0 || (elementValue1.elements[i].combinator.value || ' ') !== (elementValue2.elements[i].combinator.value || ' ')) {
                          return false;
                      }
                  }
                  if (!this.isElementValuesEqual(elementValue1.elements[i].value, elementValue2.elements[i].value)) {
                      return false;
                  }
              }
              return true;
          }
          return false;
      },
      extendSelector:function (matches, selectorPath, replacementSelector, isVisible) {
  
          // for a set of matches, replace each match with the replacement selector
  
          var currentSelectorPathIndex = 0,
              currentSelectorPathElementIndex = 0,
              path = [],
              matchIndex,
              selector,
              firstElement,
              match,
              newElements;
  
          for (matchIndex = 0; matchIndex < matches.length; matchIndex++) {
              match = matches[matchIndex];
              selector = selectorPath[match.pathIndex];
              firstElement = new tree.Element(
                  match.initialCombinator,
                  replacementSelector.elements[0].value,
                  replacementSelector.elements[0].getIndex(),
                  replacementSelector.elements[0].fileInfo()
              );
  
              if (match.pathIndex > currentSelectorPathIndex && currentSelectorPathElementIndex > 0) {
                  path[path.length - 1].elements = path[path.length - 1]
                      .elements.concat(selectorPath[currentSelectorPathIndex].elements.slice(currentSelectorPathElementIndex));
                  currentSelectorPathElementIndex = 0;
                  currentSelectorPathIndex++;
              }
  
              newElements = selector.elements
                  .slice(currentSelectorPathElementIndex, match.index)
                  .concat([firstElement])
                  .concat(replacementSelector.elements.slice(1));
  
              if (currentSelectorPathIndex === match.pathIndex && matchIndex > 0) {
                  path[path.length - 1].elements =
                      path[path.length - 1].elements.concat(newElements);
              } else {
                  path = path.concat(selectorPath.slice(currentSelectorPathIndex, match.pathIndex));
  
                  path.push(new tree.Selector(
                      newElements
                  ));
              }
              currentSelectorPathIndex = match.endPathIndex;
              currentSelectorPathElementIndex = match.endPathElementIndex;
              if (currentSelectorPathElementIndex >= selectorPath[currentSelectorPathIndex].elements.length) {
                  currentSelectorPathElementIndex = 0;
                  currentSelectorPathIndex++;
              }
          }
  
          if (currentSelectorPathIndex < selectorPath.length && currentSelectorPathElementIndex > 0) {
              path[path.length - 1].elements = path[path.length - 1]
                  .elements.concat(selectorPath[currentSelectorPathIndex].elements.slice(currentSelectorPathElementIndex));
              currentSelectorPathIndex++;
          }
  
          path = path.concat(selectorPath.slice(currentSelectorPathIndex, selectorPath.length));
          path = path.map(function (currentValue) {
              // we can re-use elements here, because the visibility property matters only for selectors
              var derived = currentValue.createDerived(currentValue.elements);
              if (isVisible) {
                  derived.ensureVisibility();
              } else {
                  derived.ensureInvisibility();
              }
              return derived;
          });
          return path;
      },
      visitMedia: function (mediaNode, visitArgs) {
          var newAllExtends = mediaNode.allExtends.concat(this.allExtendsStack[this.allExtendsStack.length - 1]);
          newAllExtends = newAllExtends.concat(this.doExtendChaining(newAllExtends, mediaNode.allExtends));
          this.allExtendsStack.push(newAllExtends);
      },
      visitMediaOut: function (mediaNode) {
          var lastIndex = this.allExtendsStack.length - 1;
          this.allExtendsStack.length = lastIndex;
      },
      visitAtRule: function (atRuleNode, visitArgs) {
          var newAllExtends = atRuleNode.allExtends.concat(this.allExtendsStack[this.allExtendsStack.length - 1]);
          newAllExtends = newAllExtends.concat(this.doExtendChaining(newAllExtends, atRuleNode.allExtends));
          this.allExtendsStack.push(newAllExtends);
      },
      visitAtRuleOut: function (atRuleNode) {
          var lastIndex = this.allExtendsStack.length - 1;
          this.allExtendsStack.length = lastIndex;
      }
  };
  
  module.exports = ProcessExtendsVisitor;
  
  },{"../logger":37,"../tree":65,"../utils":86,"./visitor":94}],88:[function(require,module,exports){
  function ImportSequencer(onSequencerEmpty) {
      this.imports = [];
      this.variableImports = [];
      this._onSequencerEmpty = onSequencerEmpty;
      this._currentDepth = 0;
  }
  
  ImportSequencer.prototype.addImport = function(callback) {
      var importSequencer = this,
          importItem = {
              callback: callback,
              args: null,
              isReady: false
          };
      this.imports.push(importItem);
      return function() {
          importItem.args = Array.prototype.slice.call(arguments, 0);
          importItem.isReady = true;
          importSequencer.tryRun();
      };
  };
  
  ImportSequencer.prototype.addVariableImport = function(callback) {
      this.variableImports.push(callback);
  };
  
  ImportSequencer.prototype.tryRun = function() {
      this._currentDepth++;
      try {
          while (true) {
              while (this.imports.length > 0) {
                  var importItem = this.imports[0];
                  if (!importItem.isReady) {
                      return;
                  }
                  this.imports = this.imports.slice(1);
                  importItem.callback.apply(null, importItem.args);
              }
              if (this.variableImports.length === 0) {
                  break;
              }
              var variableImport = this.variableImports[0];
              this.variableImports = this.variableImports.slice(1);
              variableImport();
          }
      } finally {
          this._currentDepth--;
      }
      if (this._currentDepth === 0 && this._onSequencerEmpty) {
          this._onSequencerEmpty();
      }
  };
  
  module.exports = ImportSequencer;
  
  },{}],89:[function(require,module,exports){
  var contexts = require("../contexts"),
      Visitor = require("./visitor"),
      ImportSequencer = require("./import-sequencer"),
      utils = require("../utils");
  
  var ImportVisitor = function(importer, finish) {
  
      this._visitor = new Visitor(this);
      this._importer = importer;
      this._finish = finish;
      this.context = new contexts.Eval();
      this.importCount = 0;
      this.onceFileDetectionMap = {};
      this.recursionDetector = {};
      this._sequencer = new ImportSequencer(this._onSequencerEmpty.bind(this));
  };
  
  ImportVisitor.prototype = {
      isReplacing: false,
      run: function (root) {
          try {
              // process the contents
              this._visitor.visit(root);
          }
          catch (e) {
              this.error = e;
          }
  
          this.isFinished = true;
          this._sequencer.tryRun();
      },
      _onSequencerEmpty: function() {
          if (!this.isFinished) {
              return;
          }
          this._finish(this.error);
      },
      visitImport: function (importNode, visitArgs) {
          var inlineCSS = importNode.options.inline;
  
          if (!importNode.css || inlineCSS) {
  
              var context = new contexts.Eval(this.context, utils.copyArray(this.context.frames));
              var importParent = context.frames[0];
  
              this.importCount++;
              if (importNode.isVariableImport()) {
                  this._sequencer.addVariableImport(this.processImportNode.bind(this, importNode, context, importParent));
              } else {
                  this.processImportNode(importNode, context, importParent);
              }
          }
          visitArgs.visitDeeper = false;
      },
      processImportNode: function(importNode, context, importParent) {
          var evaldImportNode,
              inlineCSS = importNode.options.inline;
  
          try {
              evaldImportNode = importNode.evalForImport(context);
          } catch (e) {
              if (!e.filename) { e.index = importNode.getIndex(); e.filename = importNode.fileInfo().filename; }
              // attempt to eval properly and treat as css
              importNode.css = true;
              // if that fails, this error will be thrown
              importNode.error = e;
          }
  
          if (evaldImportNode && (!evaldImportNode.css || inlineCSS)) {
  
              if (evaldImportNode.options.multiple) {
                  context.importMultiple = true;
              }
  
              // try appending if we haven't determined if it is css or not
              var tryAppendLessExtension = evaldImportNode.css === undefined;
  
              for (var i = 0; i < importParent.rules.length; i++) {
                  if (importParent.rules[i] === importNode) {
                      importParent.rules[i] = evaldImportNode;
                      break;
                  }
              }
  
              var onImported = this.onImported.bind(this, evaldImportNode, context),
                  sequencedOnImported = this._sequencer.addImport(onImported);
  
              this._importer.push(evaldImportNode.getPath(), tryAppendLessExtension, evaldImportNode.fileInfo(),
                  evaldImportNode.options, sequencedOnImported);
          } else {
              this.importCount--;
              if (this.isFinished) {
                  this._sequencer.tryRun();
              }
          }
      },
      onImported: function (importNode, context, e, root, importedAtRoot, fullPath) {
          if (e) {
              if (!e.filename) {
                  e.index = importNode.getIndex(); e.filename = importNode.fileInfo().filename;
              }
              this.error = e;
          }
  
          var importVisitor = this,
              inlineCSS = importNode.options.inline,
              isPlugin = importNode.options.isPlugin,
              isOptional = importNode.options.optional,
              duplicateImport = importedAtRoot || fullPath in importVisitor.recursionDetector;
  
          if (!context.importMultiple) {
              if (duplicateImport) {
                  importNode.skip = true;
              } else {
                  importNode.skip = function() {
                      if (fullPath in importVisitor.onceFileDetectionMap) {
                          return true;
                      }
                      importVisitor.onceFileDetectionMap[fullPath] = true;
                      return false;
                  };
              }
          }
  
          if (!fullPath && isOptional) {
              importNode.skip = true;
          }
  
          if (root) {
              importNode.root = root;
              importNode.importedFilename = fullPath;
  
              if (!inlineCSS && !isPlugin && (context.importMultiple || !duplicateImport)) {
                  importVisitor.recursionDetector[fullPath] = true;
  
                  var oldContext = this.context;
                  this.context = context;
                  try {
                      this._visitor.visit(root);
                  } catch (e) {
                      this.error = e;
                  }
                  this.context = oldContext;
              }
          }
  
          importVisitor.importCount--;
  
          if (importVisitor.isFinished) {
              importVisitor._sequencer.tryRun();
          }
      },
      visitDeclaration: function (declNode, visitArgs) {
          if (declNode.value.type === "DetachedRuleset") {
              this.context.frames.unshift(declNode);
          } else {
              visitArgs.visitDeeper = false;
          }
      },
      visitDeclarationOut: function(declNode) {
          if (declNode.value.type === "DetachedRuleset") {
              this.context.frames.shift();
          }
      },
      visitAtRule: function (atRuleNode, visitArgs) {
          this.context.frames.unshift(atRuleNode);
      },
      visitAtRuleOut: function (atRuleNode) {
          this.context.frames.shift();
      },
      visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
          this.context.frames.unshift(mixinDefinitionNode);
      },
      visitMixinDefinitionOut: function (mixinDefinitionNode) {
          this.context.frames.shift();
      },
      visitRuleset: function (rulesetNode, visitArgs) {
          this.context.frames.unshift(rulesetNode);
      },
      visitRulesetOut: function (rulesetNode) {
          this.context.frames.shift();
      },
      visitMedia: function (mediaNode, visitArgs) {
          this.context.frames.unshift(mediaNode.rules[0]);
      },
      visitMediaOut: function (mediaNode) {
          this.context.frames.shift();
      }
  };
  module.exports = ImportVisitor;
  
  },{"../contexts":12,"../utils":86,"./import-sequencer":88,"./visitor":94}],90:[function(require,module,exports){
  var visitors = {
      Visitor: require("./visitor"),
      ImportVisitor: require('./import-visitor'),
      MarkVisibleSelectorsVisitor: require("./set-tree-visibility-visitor"),
      ExtendVisitor: require('./extend-visitor'),
      JoinSelectorVisitor: require('./join-selector-visitor'),
      ToCSSVisitor: require('./to-css-visitor')
  };
  
  module.exports = visitors;
  
  },{"./extend-visitor":87,"./import-visitor":89,"./join-selector-visitor":91,"./set-tree-visibility-visitor":92,"./to-css-visitor":93,"./visitor":94}],91:[function(require,module,exports){
  var Visitor = require("./visitor");
  
  var JoinSelectorVisitor = function() {
      this.contexts = [[]];
      this._visitor = new Visitor(this);
  };
  
  JoinSelectorVisitor.prototype = {
      run: function (root) {
          return this._visitor.visit(root);
      },
      visitDeclaration: function (declNode, visitArgs) {
          visitArgs.visitDeeper = false;
      },
      visitMixinDefinition: function (mixinDefinitionNode, visitArgs) {
          visitArgs.visitDeeper = false;
      },
  
      visitRuleset: function (rulesetNode, visitArgs) {
          var context = this.contexts[this.contexts.length - 1],
              paths = [], selectors;
  
          this.contexts.push(paths);
  
          if (!rulesetNode.root) {
              selectors = rulesetNode.selectors;
              if (selectors) {
                  selectors = selectors.filter(function(selector) { return selector.getIsOutput(); });
                  rulesetNode.selectors = selectors.length ? selectors : (selectors = null);
                  if (selectors) { rulesetNode.joinSelectors(paths, context, selectors); }
              }
              if (!selectors) { rulesetNode.rules = null; }
              rulesetNode.paths = paths;
          }
      },
      visitRulesetOut: function (rulesetNode) {
          this.contexts.length = this.contexts.length - 1;
      },
      visitMedia: function (mediaNode, visitArgs) {
          var context = this.contexts[this.contexts.length - 1];
          mediaNode.rules[0].root = (context.length === 0 || context[0].multiMedia);
      },
      visitAtRule: function (atRuleNode, visitArgs) {
          var context = this.contexts[this.contexts.length - 1];
          if (atRuleNode.rules && atRuleNode.rules.length) {
              atRuleNode.rules[0].root = (atRuleNode.isRooted || context.length === 0 || null);
          }
      }
  };
  
  module.exports = JoinSelectorVisitor;
  
  },{"./visitor":94}],92:[function(require,module,exports){
  var SetTreeVisibilityVisitor = function(visible) {
      this.visible = visible;
  };
  SetTreeVisibilityVisitor.prototype.run = function(root) {
      this.visit(root);
  };
  SetTreeVisibilityVisitor.prototype.visitArray = function(nodes) {
      if (!nodes) {
          return nodes;
      }
  
      var cnt = nodes.length, i;
      for (i = 0; i < cnt; i++) {
          this.visit(nodes[i]);
      }
      return nodes;
  };
  SetTreeVisibilityVisitor.prototype.visit = function(node) {
      if (!node) {
          return node;
      }
      if (node.constructor === Array) {
          return this.visitArray(node);
      }
  
      if (!node.blocksVisibility || node.blocksVisibility()) {
          return node;
      }
      if (this.visible) {
          node.ensureVisibility();
      } else {
          node.ensureInvisibility();
      }
  
      node.accept(this);
      return node;
  };
  module.exports = SetTreeVisibilityVisitor;
  },{}],93:[function(require,module,exports){
  var tree = require("../tree"),
      Visitor = require("./visitor");
  
  var CSSVisitorUtils = function(context) {
      this._visitor = new Visitor(this);
      this._context = context;
  };
  
  CSSVisitorUtils.prototype = {
      containsSilentNonBlockedChild: function(bodyRules) {
          var rule;
          if (!bodyRules) {
              return false;
          }
          for (var r = 0; r < bodyRules.length; r++) {
              rule = bodyRules[r];
              if (rule.isSilent && rule.isSilent(this._context) && !rule.blocksVisibility()) {
                  // the atrule contains something that was referenced (likely by extend)
                  // therefore it needs to be shown in output too
                  return true;
              }
          }
          return false;
      },
  
      keepOnlyVisibleChilds: function(owner) {
          if (owner && owner.rules) {
              owner.rules = owner.rules.filter(function(thing) {
                  return thing.isVisible();
              });
          }
      },
  
      isEmpty: function(owner) {
          return (owner && owner.rules) 
              ? (owner.rules.length === 0) : true;
      },
  
      hasVisibleSelector: function(rulesetNode) {
          return (rulesetNode && rulesetNode.paths)
              ? (rulesetNode.paths.length > 0) : false;
      },
  
      resolveVisibility: function (node, originalRules) {
          if (!node.blocksVisibility()) {
              if (this.isEmpty(node) && !this.containsSilentNonBlockedChild(originalRules)) {
                  return ;
              }
  
              return node;
          }
  
          var compiledRulesBody = node.rules[0];
          this.keepOnlyVisibleChilds(compiledRulesBody);
  
          if (this.isEmpty(compiledRulesBody)) {
              return ;
          }
  
          node.ensureVisibility();
          node.removeVisibilityBlock();
  
          return node;
      },
  
      isVisibleRuleset: function(rulesetNode) {
          if (rulesetNode.firstRoot) {
              return true;
          }
  
          if (this.isEmpty(rulesetNode)) {
              return false;
          }
  
          if (!rulesetNode.root && !this.hasVisibleSelector(rulesetNode)) {
              return false;
          }
  
          return true;
      }
  
  };
  
  var ToCSSVisitor = function(context) {
      this._visitor = new Visitor(this);
      this._context = context;
      this.utils = new CSSVisitorUtils(context);
  };
  
  ToCSSVisitor.prototype = {
      isReplacing: true,
      run: function (root) {
          return this._visitor.visit(root);
      },
  
      visitDeclaration: function (declNode, visitArgs) {
          if (declNode.blocksVisibility() || declNode.variable) {
              return;
          }
          return declNode;
      },
  
      visitMixinDefinition: function (mixinNode, visitArgs) {
          // mixin definitions do not get eval'd - this means they keep state
          // so we have to clear that state here so it isn't used if toCSS is called twice
          mixinNode.frames = [];
      },
  
      visitExtend: function (extendNode, visitArgs) {
      },
  
      visitComment: function (commentNode, visitArgs) {
          if (commentNode.blocksVisibility() || commentNode.isSilent(this._context)) {
              return;
          }
          return commentNode;
      },
  
      visitMedia: function(mediaNode, visitArgs) {
          var originalRules = mediaNode.rules[0].rules;
          mediaNode.accept(this._visitor);
          visitArgs.visitDeeper = false;
  
          return this.utils.resolveVisibility(mediaNode, originalRules);
      },
  
      visitImport: function (importNode, visitArgs) {
          if (importNode.blocksVisibility()) {
              return ;
          }
          return importNode;
      },
  
      visitAtRule: function(atRuleNode, visitArgs) {
          if (atRuleNode.rules && atRuleNode.rules.length) {
              return this.visitAtRuleWithBody(atRuleNode, visitArgs);
          } else {
              return this.visitAtRuleWithoutBody(atRuleNode, visitArgs);
          }
      },
  
      visitAnonymous: function(anonymousNode, visitArgs) {
          if (!anonymousNode.blocksVisibility()) {
              anonymousNode.accept(this._visitor);
              return anonymousNode;
          }
      },
  
      visitAtRuleWithBody: function(atRuleNode, visitArgs) {
          // if there is only one nested ruleset and that one has no path, then it is
          // just fake ruleset
          function hasFakeRuleset(atRuleNode) {
              var bodyRules = atRuleNode.rules;
              return bodyRules.length === 1 && (!bodyRules[0].paths || bodyRules[0].paths.length === 0);
          }
          function getBodyRules(atRuleNode) {
              var nodeRules = atRuleNode.rules;
              if (hasFakeRuleset(atRuleNode)) {
                  return nodeRules[0].rules;
              }
  
              return nodeRules;
          }
          // it is still true that it is only one ruleset in array
          // this is last such moment
          // process childs
          var originalRules = getBodyRules(atRuleNode);
          atRuleNode.accept(this._visitor);
          visitArgs.visitDeeper = false;
  
          if (!this.utils.isEmpty(atRuleNode)) {
              this._mergeRules(atRuleNode.rules[0].rules);
          }
  
          return this.utils.resolveVisibility(atRuleNode, originalRules);
      },
  
      visitAtRuleWithoutBody: function(atRuleNode, visitArgs) {
          if (atRuleNode.blocksVisibility()) {
              return;
          }
  
          if (atRuleNode.name === "@charset") {
              // Only output the debug info together with subsequent @charset definitions
              // a comment (or @media statement) before the actual @charset atrule would
              // be considered illegal css as it has to be on the first line
              if (this.charset) {
                  if (atRuleNode.debugInfo) {
                      var comment = new tree.Comment("/* " + atRuleNode.toCSS(this._context).replace(/\n/g, "") + " */\n");
                      comment.debugInfo = atRuleNode.debugInfo;
                      return this._visitor.visit(comment);
                  }
                  return;
              }
              this.charset = true;
          }
  
          return atRuleNode;
      },
  
      checkValidNodes: function(rules, isRoot) {
          if (!rules) {
              return;
          }
  
          for (var i = 0; i < rules.length; i++) {
              var ruleNode = rules[i];
              if (isRoot && ruleNode instanceof tree.Declaration && !ruleNode.variable) {
                  throw { message: "Properties must be inside selector blocks. They cannot be in the root",
                      index: ruleNode.getIndex(), filename: ruleNode.fileInfo() && ruleNode.fileInfo().filename};
              }
              if (ruleNode instanceof tree.Call) {
                  throw { message: "Function '" + ruleNode.name + "' is undefined",
                      index: ruleNode.getIndex(), filename: ruleNode.fileInfo() && ruleNode.fileInfo().filename};
              }
              if (ruleNode.type && !ruleNode.allowRoot) {
                  throw { message: ruleNode.type + " node returned by a function is not valid here",
                      index: ruleNode.getIndex(), filename: ruleNode.fileInfo() && ruleNode.fileInfo().filename};
              }
          }
      },
  
      visitRuleset: function (rulesetNode, visitArgs) {
          // at this point rulesets are nested into each other
          var rule, rulesets = [];
  
          this.checkValidNodes(rulesetNode.rules, rulesetNode.firstRoot);
  
          if (!rulesetNode.root) {
              // remove invisible paths
              this._compileRulesetPaths(rulesetNode);
  
              // remove rulesets from this ruleset body and compile them separately
              var nodeRules = rulesetNode.rules, nodeRuleCnt = nodeRules ? nodeRules.length : 0;
              for (var i = 0; i < nodeRuleCnt; ) {
                  rule = nodeRules[i];
                  if (rule && rule.rules) {
                      // visit because we are moving them out from being a child
                      rulesets.push(this._visitor.visit(rule));
                      nodeRules.splice(i, 1);
                      nodeRuleCnt--;
                      continue;
                  }
                  i++;
              }
              // accept the visitor to remove rules and refactor itself
              // then we can decide nogw whether we want it or not
              // compile body
              if (nodeRuleCnt > 0) {
                  rulesetNode.accept(this._visitor);
              } else {
                  rulesetNode.rules = null;
              }
              visitArgs.visitDeeper = false;
  
          } else { // if (! rulesetNode.root) {
              rulesetNode.accept(this._visitor);
              visitArgs.visitDeeper = false;
          }
  
          if (rulesetNode.rules) {
              this._mergeRules(rulesetNode.rules);
              this._removeDuplicateRules(rulesetNode.rules);
          }
  
          // now decide whether we keep the ruleset
          if (this.utils.isVisibleRuleset(rulesetNode)) {
              rulesetNode.ensureVisibility();
              rulesets.splice(0, 0, rulesetNode);
          }
  
          if (rulesets.length === 1) {
              return rulesets[0];
          }
          return rulesets;
      },
  
      _compileRulesetPaths: function(rulesetNode) {
          if (rulesetNode.paths) {
              rulesetNode.paths = rulesetNode.paths
                  .filter(function(p) {
                      var i;
                      if (p[0].elements[0].combinator.value === ' ') {
                          p[0].elements[0].combinator = new(tree.Combinator)('');
                      }
                      for (i = 0; i < p.length; i++) {
                          if (p[i].isVisible() && p[i].getIsOutput()) {
                              return true;
                          }
                      }
                      return false;
                  });
          }
      },
  
      _removeDuplicateRules: function(rules) {
          if (!rules) { return; }
  
          // remove duplicates
          var ruleCache = {},
              ruleList, rule, i;
  
          for (i = rules.length - 1; i >= 0 ; i--) {
              rule = rules[i];
              if (rule instanceof tree.Declaration) {
                  if (!ruleCache[rule.name]) {
                      ruleCache[rule.name] = rule;
                  } else {
                      ruleList = ruleCache[rule.name];
                      if (ruleList instanceof tree.Declaration) {
                          ruleList = ruleCache[rule.name] = [ruleCache[rule.name].toCSS(this._context)];
                      }
                      var ruleCSS = rule.toCSS(this._context);
                      if (ruleList.indexOf(ruleCSS) !== -1) {
                          rules.splice(i, 1);
                      } else {
                          ruleList.push(ruleCSS);
                      }
                  }
              }
          }
      },
  
      _mergeRules: function(rules) {
          if (!rules) {
              return; 
          }
  
          var groups    = {},
              groupsArr = [];
          
          for (var i = 0; i < rules.length; i++) {
              var rule = rules[i];
              if (rule.merge) {
                  var key = rule.name;
                  groups[key] ? rules.splice(i--, 1) : 
                      groupsArr.push(groups[key] = []);
                  groups[key].push(rule);
              }
          }
  
          groupsArr.forEach(function(group) {
              if (group.length > 0) {
                  var result = group[0],
                      space  = [],
                      comma  = [new tree.Expression(space)];
                  group.forEach(function(rule) {
                      if ((rule.merge === '+') && (space.length > 0)) {
                          comma.push(new tree.Expression(space = []));
                      }
                      space.push(rule.value);
                      result.important = result.important || rule.important;
                  });
                  result.value = new tree.Value(comma);
              }
          });
      }
  };
  
  module.exports = ToCSSVisitor;
  
  },{"../tree":65,"./visitor":94}],94:[function(require,module,exports){
  var tree = require("../tree");
  
  var _visitArgs = { visitDeeper: true },
      _hasIndexed = false;
  
  function _noop(node) {
      return node;
  }
  
  function indexNodeTypes(parent, ticker) {
      // add .typeIndex to tree node types for lookup table
      var key, child;
      for (key in parent) { 
          /* eslint guard-for-in: 0 */
          child = parent[key];
          switch (typeof child) {
              case "function":
                  // ignore bound functions directly on tree which do not have a prototype
                  // or aren't nodes
                  if (child.prototype && child.prototype.type) {
                      child.prototype.typeIndex = ticker++;
                  }
                  break;
              case "object":
                  ticker = indexNodeTypes(child, ticker);
                  break;
          
          }
      }
      return ticker;
  }
  
  var Visitor = function(implementation) {
      this._implementation = implementation;
      this._visitFnCache = [];
  
      if (!_hasIndexed) {
          indexNodeTypes(tree, 1);
          _hasIndexed = true;
      }
  };
  
  Visitor.prototype = {
      visit: function(node) {
          if (!node) {
              return node;
          }
  
          var nodeTypeIndex = node.typeIndex;
          if (!nodeTypeIndex) {
              return node;
          }
  
          var visitFnCache = this._visitFnCache,
              impl = this._implementation,
              aryIndx = nodeTypeIndex << 1,
              outAryIndex = aryIndx | 1,
              func = visitFnCache[aryIndx],
              funcOut = visitFnCache[outAryIndex],
              visitArgs = _visitArgs,
              fnName;
  
          visitArgs.visitDeeper = true;
  
          if (!func) {
              fnName = "visit" + node.type;
              func = impl[fnName] || _noop;
              funcOut = impl[fnName + "Out"] || _noop;
              visitFnCache[aryIndx] = func;
              visitFnCache[outAryIndex] = funcOut;
          }
  
          if (func !== _noop) {
              var newNode = func.call(impl, node, visitArgs);
              if (impl.isReplacing) {
                  node = newNode;
              }
          }
  
          if (visitArgs.visitDeeper && node && node.accept) {
              node.accept(this);
          }
  
          if (funcOut != _noop) {
              funcOut.call(impl, node);
          }
  
          return node;
      },
      visitArray: function(nodes, nonReplacing) {
          if (!nodes) {
              return nodes;
          }
  
          var cnt = nodes.length, i;
  
          // Non-replacing
          if (nonReplacing || !this._implementation.isReplacing) {
              for (i = 0; i < cnt; i++) {
                  this.visit(nodes[i]);
              }
              return nodes;
          }
  
          // Replacing
          var out = [];
          for (i = 0; i < cnt; i++) {
              var evald = this.visit(nodes[i]);
              if (evald === undefined) { continue; }
              if (!evald.splice) {
                  out.push(evald);
              } else if (evald.length) {
                  this.flatten(evald, out);
              }
          }
          return out;
      },
      flatten: function(arr, out) {
          if (!out) {
              out = [];
          }
  
          var cnt, i, item,
              nestedCnt, j, nestedItem;
  
          for (i = 0, cnt = arr.length; i < cnt; i++) {
              item = arr[i];
              if (item === undefined) {
                  continue;
              }
              if (!item.splice) {
                  out.push(item);
                  continue;
              }
  
              for (j = 0, nestedCnt = item.length; j < nestedCnt; j++) {
                  nestedItem = item[j];
                  if (nestedItem === undefined) {
                      continue;
                  }
                  if (!nestedItem.splice) {
                      out.push(nestedItem);
                  } else if (nestedItem.length) {
                      this.flatten(nestedItem, out);
                  }
              }
          }
  
          return out;
      }
  };
  module.exports = Visitor;
  
  },{"../tree":65}],95:[function(require,module,exports){
  "use strict";
  
  // rawAsap provides everything we need except exception management.
  var rawAsap = require("./raw");
  // RawTasks are recycled to reduce GC churn.
  var freeTasks = [];
  // We queue errors to ensure they are thrown in right order (FIFO).
  // Array-as-queue is good enough here, since we are just dealing with exceptions.
  var pendingErrors = [];
  var requestErrorThrow = rawAsap.makeRequestCallFromTimer(throwFirstError);
  
  function throwFirstError() {
      if (pendingErrors.length) {
          throw pendingErrors.shift();
      }
  }
  
  /**
   * Calls a task as soon as possible after returning, in its own event, with priority
   * over other events like animation, reflow, and repaint. An error thrown from an
   * event will not interrupt, nor even substantially slow down the processing of
   * other events, but will be rather postponed to a lower priority event.
   * @param {{call}} task A callable object, typically a function that takes no
   * arguments.
   */
  module.exports = asap;
  function asap(task) {
      var rawTask;
      if (freeTasks.length) {
          rawTask = freeTasks.pop();
      } else {
          rawTask = new RawTask();
      }
      rawTask.task = task;
      rawAsap(rawTask);
  }
  
  // We wrap tasks with recyclable task objects.  A task object implements
  // `call`, just like a function.
  function RawTask() {
      this.task = null;
  }
  
  // The sole purpose of wrapping the task is to catch the exception and recycle
  // the task object after its single use.
  RawTask.prototype.call = function () {
      try {
          this.task.call();
      } catch (error) {
          if (asap.onerror) {
              // This hook exists purely for testing purposes.
              // Its name will be periodically randomized to break any code that
              // depends on its existence.
              asap.onerror(error);
          } else {
              // In a web browser, exceptions are not fatal. However, to avoid
              // slowing down the queue of pending tasks, we rethrow the error in a
              // lower priority turn.
              pendingErrors.push(error);
              requestErrorThrow();
          }
      } finally {
          this.task = null;
          freeTasks[freeTasks.length] = this;
      }
  };
  
  },{"./raw":96}],96:[function(require,module,exports){
  (function (global){
  "use strict";
  
  // Use the fastest means possible to execute a task in its own turn, with
  // priority over other events including IO, animation, reflow, and redraw
  // events in browsers.
  //
  // An exception thrown by a task will permanently interrupt the processing of
  // subsequent tasks. The higher level `asap` function ensures that if an
  // exception is thrown by a task, that the task queue will continue flushing as
  // soon as possible, but if you use `rawAsap` directly, you are responsible to
  // either ensure that no exceptions are thrown from your task, or to manually
  // call `rawAsap.requestFlush` if an exception is thrown.
  module.exports = rawAsap;
  function rawAsap(task) {
      if (!queue.length) {
          requestFlush();
          flushing = true;
      }
      // Equivalent to push, but avoids a function call.
      queue[queue.length] = task;
  }
  
  var queue = [];
  // Once a flush has been requested, no further calls to `requestFlush` are
  // necessary until the next `flush` completes.
  var flushing = false;
  // `requestFlush` is an implementation-specific method that attempts to kick
  // off a `flush` event as quickly as possible. `flush` will attempt to exhaust
  // the event queue before yielding to the browser's own event loop.
  var requestFlush;
  // The position of the next task to execute in the task queue. This is
  // preserved between calls to `flush` so that it can be resumed if
  // a task throws an exception.
  var index = 0;
  // If a task schedules additional tasks recursively, the task queue can grow
  // unbounded. To prevent memory exhaustion, the task queue will periodically
  // truncate already-completed tasks.
  var capacity = 1024;
  
  // The flush function processes all tasks that have been scheduled with
  // `rawAsap` unless and until one of those tasks throws an exception.
  // If a task throws an exception, `flush` ensures that its state will remain
  // consistent and will resume where it left off when called again.
  // However, `flush` does not make any arrangements to be called again if an
  // exception is thrown.
  function flush() {
      while (index < queue.length) {
          var currentIndex = index;
          // Advance the index before calling the task. This ensures that we will
          // begin flushing on the next task the task throws an error.
          index = index + 1;
          queue[currentIndex].call();
          // Prevent leaking memory for long chains of recursive calls to `asap`.
          // If we call `asap` within tasks scheduled by `asap`, the queue will
          // grow, but to avoid an O(n) walk for every task we execute, we don't
          // shift tasks off the queue after they have been executed.
          // Instead, we periodically shift 1024 tasks off the queue.
          if (index > capacity) {
              // Manually shift all values starting at the index back to the
              // beginning of the queue.
              for (var scan = 0, newLength = queue.length - index; scan < newLength; scan++) {
                  queue[scan] = queue[scan + index];
              }
              queue.length -= index;
              index = 0;
          }
      }
      queue.length = 0;
      index = 0;
      flushing = false;
  }
  
  // `requestFlush` is implemented using a strategy based on data collected from
  // every available SauceLabs Selenium web driver worker at time of writing.
  // https://docs.google.com/spreadsheets/d/1mG-5UYGup5qxGdEMWkhP6BWCz053NUb2E1QoUTU16uA/edit#gid=783724593
  
  // Safari 6 and 6.1 for desktop, iPad, and iPhone are the only browsers that
  // have WebKitMutationObserver but not un-prefixed MutationObserver.
  // Must use `global` or `self` instead of `window` to work in both frames and web
  // workers. `global` is a provision of Browserify, Mr, Mrs, or Mop.
  
  /* globals self */
  var scope = typeof global !== "undefined" ? global : self;
  var BrowserMutationObserver = scope.MutationObserver || scope.WebKitMutationObserver;
  
  // MutationObservers are desirable because they have high priority and work
  // reliably everywhere they are implemented.
  // They are implemented in all modern browsers.
  //
  // - Android 4-4.3
  // - Chrome 26-34
  // - Firefox 14-29
  // - Internet Explorer 11
  // - iPad Safari 6-7.1
  // - iPhone Safari 7-7.1
  // - Safari 6-7
  if (typeof BrowserMutationObserver === "function") {
      requestFlush = makeRequestCallFromMutationObserver(flush);
  
  // MessageChannels are desirable because they give direct access to the HTML
  // task queue, are implemented in Internet Explorer 10, Safari 5.0-1, and Opera
  // 11-12, and in web workers in many engines.
  // Although message channels yield to any queued rendering and IO tasks, they
  // would be better than imposing the 4ms delay of timers.
  // However, they do not work reliably in Internet Explorer or Safari.
  
  // Internet Explorer 10 is the only browser that has setImmediate but does
  // not have MutationObservers.
  // Although setImmediate yields to the browser's renderer, it would be
  // preferrable to falling back to setTimeout since it does not have
  // the minimum 4ms penalty.
  // Unfortunately there appears to be a bug in Internet Explorer 10 Mobile (and
  // Desktop to a lesser extent) that renders both setImmediate and
  // MessageChannel useless for the purposes of ASAP.
  // https://github.com/kriskowal/q/issues/396
  
  // Timers are implemented universally.
  // We fall back to timers in workers in most engines, and in foreground
  // contexts in the following browsers.
  // However, note that even this simple case requires nuances to operate in a
  // broad spectrum of browsers.
  //
  // - Firefox 3-13
  // - Internet Explorer 6-9
  // - iPad Safari 4.3
  // - Lynx 2.8.7
  } else {
      requestFlush = makeRequestCallFromTimer(flush);
  }
  
  // `requestFlush` requests that the high priority event queue be flushed as
  // soon as possible.
  // This is useful to prevent an error thrown in a task from stalling the event
  // queue if the exception handled by Node.js’s
  // `process.on("uncaughtException")` or by a domain.
  rawAsap.requestFlush = requestFlush;
  
  // To request a high priority event, we induce a mutation observer by toggling
  // the text of a text node between "1" and "-1".
  function makeRequestCallFromMutationObserver(callback) {
      var toggle = 1;
      var observer = new BrowserMutationObserver(callback);
      var node = document.createTextNode("");
      observer.observe(node, {characterData: true});
      return function requestCall() {
          toggle = -toggle;
          node.data = toggle;
      };
  }
  
  // The message channel technique was discovered by Malte Ubl and was the
  // original foundation for this library.
  // http://www.nonblocking.io/2011/06/windownexttick.html
  
  // Safari 6.0.5 (at least) intermittently fails to create message ports on a
  // page's first load. Thankfully, this version of Safari supports
  // MutationObservers, so we don't need to fall back in that case.
  
  // function makeRequestCallFromMessageChannel(callback) {
  //     var channel = new MessageChannel();
  //     channel.port1.onmessage = callback;
  //     return function requestCall() {
  //         channel.port2.postMessage(0);
  //     };
  // }
  
  // For reasons explained above, we are also unable to use `setImmediate`
  // under any circumstances.
  // Even if we were, there is another bug in Internet Explorer 10.
  // It is not sufficient to assign `setImmediate` to `requestFlush` because
  // `setImmediate` must be called *by name* and therefore must be wrapped in a
  // closure.
  // Never forget.
  
  // function makeRequestCallFromSetImmediate(callback) {
  //     return function requestCall() {
  //         setImmediate(callback);
  //     };
  // }
  
  // Safari 6.0 has a problem where timers will get lost while the user is
  // scrolling. This problem does not impact ASAP because Safari 6.0 supports
  // mutation observers, so that implementation is used instead.
  // However, if we ever elect to use timers in Safari, the prevalent work-around
  // is to add a scroll event listener that calls for a flush.
  
  // `setTimeout` does not call the passed callback if the delay is less than
  // approximately 7 in web workers in Firefox 8 through 18, and sometimes not
  // even then.
  
  function makeRequestCallFromTimer(callback) {
      return function requestCall() {
          // We dispatch a timeout with a specified delay of 0 for engines that
          // can reliably accommodate that request. This will usually be snapped
          // to a 4 milisecond delay, but once we're flushing, there's no delay
          // between events.
          var timeoutHandle = setTimeout(handleTimer, 0);
          // However, since this timer gets frequently dropped in Firefox
          // workers, we enlist an interval handle that will try to fire
          // an event 20 times per second until it succeeds.
          var intervalHandle = setInterval(handleTimer, 50);
  
          function handleTimer() {
              // Whichever timer succeeds will cancel both timers and
              // execute the callback.
              clearTimeout(timeoutHandle);
              clearInterval(intervalHandle);
              callback();
          }
      };
  }
  
  // This is for `asap.js` only.
  // Its name will be periodically randomized to break any code that depends on
  // its existence.
  rawAsap.makeRequestCallFromTimer = makeRequestCallFromTimer;
  
  // ASAP was originally a nextTick shim included in Q. This was factored out
  // into this ASAP package. It was later adapted to RSVP which made further
  // amendments. These decisions, particularly to marginalize MessageChannel and
  // to capture the MutationObserver implementation in a closure, were integrated
  // back into ASAP proper.
  // https://github.com/tildeio/rsvp.js/blob/cddf7232546a9cf858524b75cde6f9edf72620a7/lib/rsvp/asap.js
  
  }).call(this,typeof global !== "undefined" ? global : typeof self !== "undefined" ? self : typeof window !== "undefined" ? window : {})
  },{}],97:[function(require,module,exports){
  'use strict';
  
  var asap = require('asap/raw');
  
  function noop() {}
  
  // States:
  //
  // 0 - pending
  // 1 - fulfilled with _value
  // 2 - rejected with _value
  // 3 - adopted the state of another promise, _value
  //
  // once the state is no longer pending (0) it is immutable
  
  // All `_` prefixed properties will be reduced to `_{random number}`
  // at build time to obfuscate them and discourage their use.
  // We don't use symbols or Object.defineProperty to fully hide them
  // because the performance isn't good enough.
  
  
  // to avoid using try/catch inside critical functions, we
  // extract them to here.
  var LAST_ERROR = null;
  var IS_ERROR = {};
  function getThen(obj) {
    try {
      return obj.then;
    } catch (ex) {
      LAST_ERROR = ex;
      return IS_ERROR;
    }
  }
  
  function tryCallOne(fn, a) {
    try {
      return fn(a);
    } catch (ex) {
      LAST_ERROR = ex;
      return IS_ERROR;
    }
  }
  function tryCallTwo(fn, a, b) {
    try {
      fn(a, b);
    } catch (ex) {
      LAST_ERROR = ex;
      return IS_ERROR;
    }
  }
  
  module.exports = Promise;
  
  function Promise(fn) {
    if (typeof this !== 'object') {
      throw new TypeError('Promises must be constructed via new');
    }
    if (typeof fn !== 'function') {
      throw new TypeError('Promise constructor\'s argument is not a function');
    }
    this._40 = 0;
    this._65 = 0;
    this._55 = null;
    this._72 = null;
    if (fn === noop) return;
    doResolve(fn, this);
  }
  Promise._37 = null;
  Promise._87 = null;
  Promise._61 = noop;
  
  Promise.prototype.then = function(onFulfilled, onRejected) {
    if (this.constructor !== Promise) {
      return safeThen(this, onFulfilled, onRejected);
    }
    var res = new Promise(noop);
    handle(this, new Handler(onFulfilled, onRejected, res));
    return res;
  };
  
  function safeThen(self, onFulfilled, onRejected) {
    return new self.constructor(function (resolve, reject) {
      var res = new Promise(noop);
      res.then(resolve, reject);
      handle(self, new Handler(onFulfilled, onRejected, res));
    });
  }
  function handle(self, deferred) {
    while (self._65 === 3) {
      self = self._55;
    }
    if (Promise._37) {
      Promise._37(self);
    }
    if (self._65 === 0) {
      if (self._40 === 0) {
        self._40 = 1;
        self._72 = deferred;
        return;
      }
      if (self._40 === 1) {
        self._40 = 2;
        self._72 = [self._72, deferred];
        return;
      }
      self._72.push(deferred);
      return;
    }
    handleResolved(self, deferred);
  }
  
  function handleResolved(self, deferred) {
    asap(function() {
      var cb = self._65 === 1 ? deferred.onFulfilled : deferred.onRejected;
      if (cb === null) {
        if (self._65 === 1) {
          resolve(deferred.promise, self._55);
        } else {
          reject(deferred.promise, self._55);
        }
        return;
      }
      var ret = tryCallOne(cb, self._55);
      if (ret === IS_ERROR) {
        reject(deferred.promise, LAST_ERROR);
      } else {
        resolve(deferred.promise, ret);
      }
    });
  }
  function resolve(self, newValue) {
    // Promise Resolution Procedure: https://github.com/promises-aplus/promises-spec#the-promise-resolution-procedure
    if (newValue === self) {
      return reject(
        self,
        new TypeError('A promise cannot be resolved with itself.')
      );
    }
    if (
      newValue &&
      (typeof newValue === 'object' || typeof newValue === 'function')
    ) {
      var then = getThen(newValue);
      if (then === IS_ERROR) {
        return reject(self, LAST_ERROR);
      }
      if (
        then === self.then &&
        newValue instanceof Promise
      ) {
        self._65 = 3;
        self._55 = newValue;
        finale(self);
        return;
      } else if (typeof then === 'function') {
        doResolve(then.bind(newValue), self);
        return;
      }
    }
    self._65 = 1;
    self._55 = newValue;
    finale(self);
  }
  
  function reject(self, newValue) {
    self._65 = 2;
    self._55 = newValue;
    if (Promise._87) {
      Promise._87(self, newValue);
    }
    finale(self);
  }
  function finale(self) {
    if (self._40 === 1) {
      handle(self, self._72);
      self._72 = null;
    }
    if (self._40 === 2) {
      for (var i = 0; i < self._72.length; i++) {
        handle(self, self._72[i]);
      }
      self._72 = null;
    }
  }
  
  function Handler(onFulfilled, onRejected, promise){
    this.onFulfilled = typeof onFulfilled === 'function' ? onFulfilled : null;
    this.onRejected = typeof onRejected === 'function' ? onRejected : null;
    this.promise = promise;
  }
  
  /**
   * Take a potentially misbehaving resolver function and make sure
   * onFulfilled and onRejected are only called once.
   *
   * Makes no guarantees about asynchrony.
   */
  function doResolve(fn, promise) {
    var done = false;
    var res = tryCallTwo(fn, function (value) {
      if (done) return;
      done = true;
      resolve(promise, value);
    }, function (reason) {
      if (done) return;
      done = true;
      reject(promise, reason);
    });
    if (!done && res === IS_ERROR) {
      done = true;
      reject(promise, LAST_ERROR);
    }
  }
  
  },{"asap/raw":96}],98:[function(require,module,exports){
  'use strict';
  
  //This file contains the ES6 extensions to the core Promises/A+ API
  
  var Promise = require('./core.js');
  
  module.exports = Promise;
  
  /* Static Functions */
  
  var TRUE = valuePromise(true);
  var FALSE = valuePromise(false);
  var NULL = valuePromise(null);
  var UNDEFINED = valuePromise(undefined);
  var ZERO = valuePromise(0);
  var EMPTYSTRING = valuePromise('');
  
  function valuePromise(value) {
    var p = new Promise(Promise._61);
    p._65 = 1;
    p._55 = value;
    return p;
  }
  Promise.resolve = function (value) {
    if (value instanceof Promise) return value;
  
    if (value === null) return NULL;
    if (value === undefined) return UNDEFINED;
    if (value === true) return TRUE;
    if (value === false) return FALSE;
    if (value === 0) return ZERO;
    if (value === '') return EMPTYSTRING;
  
    if (typeof value === 'object' || typeof value === 'function') {
      try {
        var then = value.then;
        if (typeof then === 'function') {
          return new Promise(then.bind(value));
        }
      } catch (ex) {
        return new Promise(function (resolve, reject) {
          reject(ex);
        });
      }
    }
    return valuePromise(value);
  };
  
  Promise.all = function (arr) {
    var args = Array.prototype.slice.call(arr);
  
    return new Promise(function (resolve, reject) {
      if (args.length === 0) return resolve([]);
      var remaining = args.length;
      function res(i, val) {
        if (val && (typeof val === 'object' || typeof val === 'function')) {
          if (val instanceof Promise && val.then === Promise.prototype.then) {
            while (val._65 === 3) {
              val = val._55;
            }
            if (val._65 === 1) return res(i, val._55);
            if (val._65 === 2) reject(val._55);
            val.then(function (val) {
              res(i, val);
            }, reject);
            return;
          } else {
            var then = val.then;
            if (typeof then === 'function') {
              var p = new Promise(then.bind(val));
              p.then(function (val) {
                res(i, val);
              }, reject);
              return;
            }
          }
        }
        args[i] = val;
        if (--remaining === 0) {
          resolve(args);
        }
      }
      for (var i = 0; i < args.length; i++) {
        res(i, args[i]);
      }
    });
  };
  
  Promise.reject = function (value) {
    return new Promise(function (resolve, reject) {
      reject(value);
    });
  };
  
  Promise.race = function (values) {
    return new Promise(function (resolve, reject) {
      values.forEach(function(value){
        Promise.resolve(value).then(resolve, reject);
      });
    });
  };
  
  /* Prototype Methods */
  
  Promise.prototype['catch'] = function (onRejected) {
    return this.then(null, onRejected);
  };
  
  },{"./core.js":97}],99:[function(require,module,exports){
  // should work in any browser without browserify
  
  if (typeof Promise.prototype.done !== 'function') {
    Promise.prototype.done = function (onFulfilled, onRejected) {
      var self = arguments.length ? this.then.apply(this, arguments) : this
      self.then(null, function (err) {
        setTimeout(function () {
          throw err
        }, 0)
      })
    }
  }
  },{}],100:[function(require,module,exports){
  // not "use strict" so we can declare global "Promise"
  
  var asap = require('asap');
  
  if (typeof Promise === 'undefined') {
    Promise = require('./lib/core.js')
    require('./lib/es6-extensions.js')
  }
  
  require('./polyfill-done.js');
  
  },{"./lib/core.js":97,"./lib/es6-extensions.js":98,"./polyfill-done.js":99,"asap":95}]},{},[2])(2)
  });