text: 'use strict';
  
  var _typeof = typeof Symbol === "function" && typeof Symbol.iterator === "symbol" ? function (obj) {
      return typeof obj;
  } : function (obj) {
      return obj && typeof Symbol === "function" && obj.constructor === Symbol && obj !== Symbol.prototype ? "symbol" : typeof obj;
  };
  
  /**
   * @fileOverview Kickass library to create and place poppers near their reference elements.
   * @version {{version}}
   * @license
   * Copyright (c) 2016 Federico Zivolo and contributors
   *
   * Permission is hereby granted, free of charge, to any person obtaining a copy
   * of this software and associated documentation files (the "Software"), to deal
   * in the Software without restriction, including without limitation the rights
   * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
   * copies of the Software, and to permit persons to whom the Software is
   * furnished to do so, subject to the following conditions:
   *
   * The above copyright notice and this permission notice shall be included in all
   * copies or substantial portions of the Software.
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
   * SOFTWARE.
   */
  
  //
  // Cross module loader
  // Supported: Node, AMD, Browser globals
  //
  (function (root, factory) {
      if (typeof define === 'function' && define.amd) {
          // AMD. Register as an anonymous module.
          define(factory);
      } else if ((typeof module === 'undefined' ? 'undefined' : _typeof(module)) === 'object' && module.exports) {
          // Node. Does not work with strict CommonJS, but
          // only CommonJS-like environments that support module.exports,
          // like Node.
          module.exports = factory();
      } else {
          // Browser globals (root is window)
          root.Popper = factory();
      }
  })(undefined, function () {
  
      'use strict';
  
      var root = window;
  
      // default options
      var DEFAULTS = {
          // placement of the popper
          placement: 'bottom',
  
          gpuAcceleration: true,
  
          // shift popper from its origin by the given amount of pixels (can be negative)
          offset: 0,
  
          // the element which will act as boundary of the popper
          boundariesElement: 'viewport',
  
          // amount of pixel used to define a minimum distance between the boundaries and the popper
          boundariesPadding: 5,
  
          // popper will try to prevent overflow following this order,
          // by default, then, it could overflow on the left and on top of the boundariesElement
          preventOverflowOrder: ['left', 'right', 'top', 'bottom'],
  
          // the behavior used by flip to change the placement of the popper
          flipBehavior: 'flip',
  
          arrowElement: '[x-arrow]',
  
          arrowOffset: 0,
  
          // list of functions used to modify the offsets before they are applied to the popper
          modifiers: ['shift', 'offset', 'preventOverflow', 'keepTogether', 'arrow', 'flip', 'applyStyle'],
  
          modifiersIgnored: [],
  
          forceAbsolute: false
      };
  
      /**
       * Create a new Popper.js instance
       * @constructor Popper
       * @param {HTMLElement} reference - The reference element used to position the popper
       * @param {HTMLElement|Object} popper
       *      The HTML element used as popper, or a configuration used to generate the popper.
       * @param {String} [popper.tagName='div'] The tag name of the generated popper.
       * @param {Array} [popper.classNames=['popper']] Array of classes to apply to the generated popper.
       * @param {Array} [popper.attributes] Array of attributes to apply, specify `attr:value` to assign a value to it.
       * @param {HTMLElement|String} [popper.parent=window.document.body] The parent element, given as HTMLElement or as query string.
       * @param {String} [popper.content=''] The content of the popper, it can be text, html, or node; if it is not text, set `contentType` to `html` or `node`.
       * @param {String} [popper.contentType='text'] If `html`, the `content` will be parsed as HTML. If `node`, it will be appended as-is.
       * @param {String} [popper.arrowTagName='div'] Same as `popper.tagName` but for the arrow element.
       * @param {Array} [popper.arrowClassNames='popper__arrow'] Same as `popper.classNames` but for the arrow element.
       * @param {String} [popper.arrowAttributes=['x-arrow']] Same as `popper.attributes` but for the arrow element.
       * @param {Object} options
       * @param {String} [options.placement=bottom]
       *      Placement of the popper accepted values: `top(-start, -end), right(-start, -end), bottom(-start, -right),
       *      left(-start, -end)`
       *
       * @param {HTMLElement|String} [options.arrowElement='[x-arrow]']
       *      The DOM Node used as arrow for the popper, or a CSS selector used to get the DOM node. It must be child of
       *      its parent Popper. Popper.js will apply to the given element the style required to align the arrow with its
       *      reference element.
       *      By default, it will look for a child node of the popper with the `x-arrow` attribute.
       *
       * @param {Boolean} [options.gpuAcceleration=true]
       *      When this property is set to true, the popper position will be applied using CSS3 translate3d, allowing the
       *      browser to use the GPU to accelerate the rendering.
       *      If set to false, the popper will be placed using `top` and `left` properties, not using the GPU.
       *
       * @param {Number} [options.offset=0]
       *      Amount of pixels the popper will be shifted (can be negative).
       *
       * @param {String|Element} [options.boundariesElement='viewport']
       *      The element which will define the boundaries of the popper position, the popper will never be placed outside
       *      of the defined boundaries (except if `keepTogether` is enabled)
       *
       * @param {Number} [options.boundariesPadding=5]
       *      Additional padding for the boundaries
       *
       * @param {Array} [options.preventOverflowOrder=['left', 'right', 'top', 'bottom']]
       *      Order used when Popper.js tries to avoid overflows from the boundaries, they will be checked in order,
       *      this means that the last ones will never overflow
       *
       * @param {String|Array} [options.flipBehavior='flip']
       *      The behavior used by the `flip` modifier to change the placement of the popper when the latter is trying to
       *      overlap its reference element. Defining `flip` as value, the placement will be flipped on
       *      its axis (`right - left`, `top - bottom`).
       *      You can even pass an array of placements (eg: `['right', 'left', 'top']` ) to manually specify
       *      how alter the placement when a flip is needed. (eg. in the above example, it would first flip from right to left,
       *      then, if even in its new placement, the popper is overlapping its reference element, it will be moved to top)
       *
       * @param {Array} [options.modifiers=[ 'shift', 'offset', 'preventOverflow', 'keepTogether', 'arrow', 'flip', 'applyStyle']]
       *      List of functions used to modify the data before they are applied to the popper, add your custom functions
       *      to this array to edit the offsets and placement.
       *      The function should reflect the @params and @returns of preventOverflow
       *
       * @param {Array} [options.modifiersIgnored=[]]
       *      Put here any built-in modifier name you want to exclude from the modifiers list
       *      The function should reflect the @params and @returns of preventOverflow
       *
       * @param {Boolean} [options.removeOnDestroy=false]
       *      Set to true if you want to automatically remove the popper when you call the `destroy` method.
       */
      function Popper(reference, popper, options) {
          this._reference = reference.jquery ? reference[0] : reference;
          this.state = {};
  
          // if the popper variable is a configuration object, parse it to generate an HTMLElement
          // generate a default popper if is not defined
          var isNotDefined = typeof popper === 'undefined' || popper === null;
          var isConfig = popper && Object.prototype.toString.call(popper) === '[object Object]';
          if (isNotDefined || isConfig) {
              this._popper = this.parse(isConfig ? popper : {});
          }
          // otherwise, use the given HTMLElement as popper
          else {
              this._popper = popper.jquery ? popper[0] : popper;
          }
  
          // with {} we create a new object with the options inside it
          this._options = Object.assign({}, DEFAULTS, options);
  
          // refactoring modifiers' list
          this._options.modifiers = this._options.modifiers.map(function (modifier) {
              // remove ignored modifiers
              if (this._options.modifiersIgnored.indexOf(modifier) !== -1) return;
  
              // set the x-placement attribute before everything else because it could be used to add margins to the popper
              // margins needs to be calculated to get the correct popper offsets
              if (modifier === 'applyStyle') {
                  this._popper.setAttribute('x-placement', this._options.placement);
              }
  
              // return predefined modifier identified by string or keep the custom one
              return this.modifiers[modifier] || modifier;
          }.bind(this));
  
          // make sure to apply the popper position before any computation
          this.state.position = this._getPosition(this._popper, this._reference);
          setStyle(this._popper, {position: this.state.position, top: 0});
  
          // fire the first update to position the popper in the right place
          this.update();
  
          // setup event listeners, they will take care of update the position in specific situations
          this._setupEventListeners();
          return this;
      }
  
      //
      // Methods
      //
      /**
       * Destroy the popper
       * @method
       * @memberof Popper
       */
      Popper.prototype.destroy = function () {
          this._popper.removeAttribute('x-placement');
          this._popper.style.left = '';
          this._popper.style.position = '';
          this._popper.style.top = '';
          this._popper.style[getSupportedPropertyName('transform')] = '';
          this._removeEventListeners();
  
          // remove the popper if user explicity asked for the deletion on destroy
          if (this._options.removeOnDestroy) {
              this._popper.remove();
          }
          return this;
      };
  
      /**
       * Updates the position of the popper, computing the new offsets and applying the new style
       * @method
       * @memberof Popper
       */
      Popper.prototype.update = function () {
          var data = {instance: this, styles: {}};
  
          // store placement inside the data object, modifiers will be able to edit `placement` if needed
          // and refer to _originalPlacement to know the original value
          data.placement = this._options.placement;
          data._originalPlacement = this._options.placement;
  
          // compute the popper and reference offsets and put them inside data.offsets
          data.offsets = this._getOffsets(this._popper, this._reference, data.placement);
  
          // get boundaries
          data.boundaries = this._getBoundaries(data, this._options.boundariesPadding, this._options.boundariesElement);
  
          data = this.runModifiers(data, this._options.modifiers);
  
          if (typeof this.state.updateCallback === 'function') {
              this.state.updateCallback(data);
          }
      };
  
      /**
       * If a function is passed, it will be executed after the initialization of popper with as first argument the Popper instance.
       * @method
       * @memberof Popper
       * @param {Function} callback
       */
      Popper.prototype.onCreate = function (callback) {
          // the createCallbacks return as first argument the popper instance
          callback(this);
          return this;
      };
  
      /**
       * If a function is passed, it will be executed after each update of popper with as first argument the set of coordinates and informations
       * used to style popper and its arrow.
       * NOTE: it doesn't get fired on the first call of the `Popper.update()` method inside the `Popper` constructor!
       * @method
       * @memberof Popper
       * @param {Function} callback
       */
      Popper.prototype.onUpdate = function (callback) {
          this.state.updateCallback = callback;
          return this;
      };
  
      /**
       * Helper used to generate poppers from a configuration file
       * @method
       * @memberof Popper
       * @param config {Object} configuration
       * @returns {HTMLElement} popper
       */
      Popper.prototype.parse = function (config) {
          var defaultConfig = {
              tagName: 'div',
              classNames: ['popper'],
              attributes: [],
              parent: root.document.body,
              content: '',
              contentType: 'text',
              arrowTagName: 'div',
              arrowClassNames: ['popper__arrow'],
              arrowAttributes: ['x-arrow']
          };
          config = Object.assign({}, defaultConfig, config);
  
          var d = root.document;
  
          var popper = d.createElement(config.tagName);
          addClassNames(popper, config.classNames);
          addAttributes(popper, config.attributes);
          if (config.contentType === 'node') {
              popper.appendChild(config.content.jquery ? config.content[0] : config.content);
          } else if (config.contentType === 'html') {
              popper.innerHTML = config.content;
          } else {
              popper.textContent = config.content;
          }
  
          if (config.arrowTagName) {
              var arrow = d.createElement(config.arrowTagName);
              addClassNames(arrow, config.arrowClassNames);
              addAttributes(arrow, config.arrowAttributes);
              popper.appendChild(arrow);
          }
  
          var parent = config.parent.jquery ? config.parent[0] : config.parent;
  
          // if the given parent is a string, use it to match an element
          // if more than one element is matched, the first one will be used as parent
          // if no elements are matched, the script will throw an error
          if (typeof parent === 'string') {
              parent = d.querySelectorAll(config.parent);
              if (parent.length > 1) {
                  console.warn('WARNING: the given `parent` query(' + config.parent + ') matched more than one element, the first one will be used');
              }
              if (parent.length === 0) {
                  throw 'ERROR: the given `parent` doesn\'t exists!';
              }
              parent = parent[0];
          }
          // if the given parent is a DOM nodes list or an array of nodes with more than one element,
          // the first one will be used as parent
          if (parent.length > 1 && parent instanceof Element === false) {
              console.warn('WARNING: you have passed as parent a list of elements, the first one will be used');
              parent = parent[0];
          }
  
          // append the generated popper to its parent
          parent.appendChild(popper);
  
          return popper;
  
          /**
           * Adds class names to the given element
           * @function
           * @ignore
           * @param {HTMLElement} target
           * @param {Array} classes
           */
          function addClassNames(element, classNames) {
              classNames.forEach(function (className) {
                  element.classList.add(className);
              });
          }
  
          /**
           * Adds attributes to the given element
           * @function
           * @ignore
           * @param {HTMLElement} target
           * @param {Array} attributes
           * @example
           * addAttributes(element, [ 'data-info:foobar' ]);
           */
          function addAttributes(element, attributes) {
              attributes.forEach(function (attribute) {
                  element.setAttribute(attribute.split(':')[0], attribute.split(':')[1] || '');
              });
          }
      };
  
      /**
       * Helper used to get the position which will be applied to the popper
       * @method
       * @memberof Popper
       * @param config {HTMLElement} popper element
       * @param reference {HTMLElement} reference element
       * @returns {String} position
       */
      Popper.prototype._getPosition = function (popper, reference) {
          var container = getOffsetParent(reference);
  
          if (this._options.forceAbsolute) {
              return 'absolute';
          }
  
          // Decide if the popper will be fixed
          // If the reference element is inside a fixed context, the popper will be fixed as well to allow them to scroll together
          var isParentFixed = isFixed(reference, container);
          return isParentFixed ? 'fixed' : 'absolute';
      };
  
      /**
       * Get offsets to the popper
       * @method
       * @memberof Popper
       * @access private
       * @param {Element} popper - the popper element
       * @param {Element} reference - the reference element (the popper will be relative to this)
       * @returns {Object} An object containing the offsets which will be applied to the popper
       */
      Popper.prototype._getOffsets = function (popper, reference, placement) {
          placement = placement.split('-')[0];
          var popperOffsets = {};
  
          popperOffsets.position = this.state.position;
          var isParentFixed = popperOffsets.position === 'fixed';
  
          //
          // Get reference element position
          //
          var referenceOffsets = getOffsetRectRelativeToCustomParent(reference, getOffsetParent(popper), isParentFixed);
  
          //
          // Get popper sizes
          //
          var popperRect = getOuterSizes(popper);
  
          //
          // Compute offsets of popper
          //
  
          // depending by the popper placement we have to compute its offsets slightly differently
          if (['right', 'left'].indexOf(placement) !== -1) {
              popperOffsets.top = referenceOffsets.top + referenceOffsets.height / 2 - popperRect.height / 2;
              if (placement === 'left') {
                  popperOffsets.left = referenceOffsets.left - popperRect.width;
              } else {
                  popperOffsets.left = referenceOffsets.right;
              }
          } else {
              popperOffsets.left = referenceOffsets.left + referenceOffsets.width / 2 - popperRect.width / 2;
              if (placement === 'top') {
                  popperOffsets.top = referenceOffsets.top - popperRect.height;
              } else {
                  popperOffsets.top = referenceOffsets.bottom;
              }
          }
  
          // Add width and height to our offsets object
          popperOffsets.width = popperRect.width;
          popperOffsets.height = popperRect.height;
  
          return {
              popper: popperOffsets,
              reference: referenceOffsets
          };
      };
  
      /**
       * Setup needed event listeners used to update the popper position
       * @method
       * @memberof Popper
       * @access private
       */
      Popper.prototype._setupEventListeners = function () {
          // NOTE: 1 DOM access here
          this.state.updateBound = this.update.bind(this);
          root.addEventListener('resize', this.state.updateBound);
          // if the boundariesElement is window we don't need to listen for the scroll event
          if (this._options.boundariesElement !== 'window') {
              var target = getScrollParent(this._reference);
              // here it could be both `body` or `documentElement` thanks to Firefox, we then check both
              if (target === root.document.body || target === root.document.documentElement) {
                  target = root;
              }
              target.addEventListener('scroll', this.state.updateBound);
              this.state.scrollTarget = target;
          }
      };
  
      /**
       * Remove event listeners used to update the popper position
       * @method
       * @memberof Popper
       * @access private
       */
      Popper.prototype._removeEventListeners = function () {
          // NOTE: 1 DOM access here
          root.removeEventListener('resize', this.state.updateBound);
          if (this._options.boundariesElement !== 'window' && this.state.scrollTarget) {
              this.state.scrollTarget.removeEventListener('scroll', this.state.updateBound);
              this.state.scrollTarget = null;
          }
          this.state.updateBound = null;
      };
  
      /**
       * Computed the boundaries limits and return them
       * @method
       * @memberof Popper
       * @access private
       * @param {Object} data - Object containing the property "offsets" generated by `_getOffsets`
       * @param {Number} padding - Boundaries padding
       * @param {Element} boundariesElement - Element used to define the boundaries
       * @returns {Object} Coordinates of the boundaries
       */
      Popper.prototype._getBoundaries = function (data, padding, boundariesElement) {
          // NOTE: 1 DOM access here
          var boundaries = {};
          var width, height;
          if (boundariesElement === 'window') {
              var body = root.document.body,
                  html = root.document.documentElement;
  
              height = Math.max(body.scrollHeight, body.offsetHeight, html.clientHeight, html.scrollHeight, html.offsetHeight);
              width = Math.max(body.scrollWidth, body.offsetWidth, html.clientWidth, html.scrollWidth, html.offsetWidth);
  
              boundaries = {
                  top: 0,
                  right: width,
                  bottom: height,
                  left: 0
              };
          } else if (boundariesElement === 'viewport') {
              var offsetParent = getOffsetParent(this._popper);
              var scrollParent = getScrollParent(this._popper);
              var offsetParentRect = getOffsetRect(offsetParent);
  
              // Thanks the fucking native API, `document.body.scrollTop` & `document.documentElement.scrollTop`
              var getScrollTopValue = function getScrollTopValue(element) {
                  return element == document.body ? Math.max(document.documentElement.scrollTop, document.body.scrollTop) : element.scrollTop;
              };
              var getScrollLeftValue = function getScrollLeftValue(element) {
                  return element == document.body ? Math.max(document.documentElement.scrollLeft, document.body.scrollLeft) : element.scrollLeft;
              };
  
              // if the popper is fixed we don't have to substract scrolling from the boundaries
              var scrollTop = data.offsets.popper.position === 'fixed' ? 0 : getScrollTopValue(scrollParent);
              var scrollLeft = data.offsets.popper.position === 'fixed' ? 0 : getScrollLeftValue(scrollParent);
  
              boundaries = {
                  top: 0 - (offsetParentRect.top - scrollTop),
                  right: root.document.documentElement.clientWidth - (offsetParentRect.left - scrollLeft),
                  bottom: root.document.documentElement.clientHeight - (offsetParentRect.top - scrollTop),
                  left: 0 - (offsetParentRect.left - scrollLeft)
              };
          } else {
              if (getOffsetParent(this._popper) === boundariesElement) {
                  boundaries = {
                      top: 0,
                      left: 0,
                      right: boundariesElement.clientWidth,
                      bottom: boundariesElement.clientHeight
                  };
              } else {
                  boundaries = getOffsetRect(boundariesElement);
              }
          }
          boundaries.left += padding;
          boundaries.right -= padding;
          boundaries.top = boundaries.top + padding;
          boundaries.bottom = boundaries.bottom - padding;
          return boundaries;
      };
  
      /**
       * Loop trough the list of modifiers and run them in order, each of them will then edit the data object
       * @method
       * @memberof Popper
       * @access public
       * @param {Object} data
       * @param {Array} modifiers
       * @param {Function} ends
       */
      Popper.prototype.runModifiers = function (data, modifiers, ends) {
          var modifiersToRun = modifiers.slice();
          if (ends !== undefined) {
              modifiersToRun = this._options.modifiers.slice(0, getArrayKeyIndex(this._options.modifiers, ends));
          }
  
          modifiersToRun.forEach(function (modifier) {
              if (isFunction(modifier)) {
                  data = modifier.call(this, data);
              }
          }.bind(this));
  
          return data;
      };
  
      /**
       * Helper used to know if the given modifier depends from another one.
       * @method
       * @memberof Popper
       * @param {String} requesting - name of requesting modifier
       * @param {String} requested - name of requested modifier
       * @returns {Boolean}
       */
      Popper.prototype.isModifierRequired = function (requesting, requested) {
          var index = getArrayKeyIndex(this._options.modifiers, requesting);
          return !!this._options.modifiers.slice(0, index).filter(function (modifier) {
              return modifier === requested;
          }).length;
      };
  
      //
      // Modifiers
      //
  
      /**
       * Modifiers list
       * @namespace Popper.modifiers
       * @memberof Popper
       * @type {Object}
       */
      Popper.prototype.modifiers = {};
  
      /**
       * Apply the computed styles to the popper element
       * @method
       * @memberof Popper.modifiers
       * @argument {Object} data - The data object generated by `update` method
       * @returns {Object} The same data object
       */
      Popper.prototype.modifiers.applyStyle = function (data) {
          // apply the final offsets to the popper
          // NOTE: 1 DOM access here
          var styles = {
              position: data.offsets.popper.position
          };
  
          // round top and left to avoid blurry text
          var left = Math.round(data.offsets.popper.left);
          var top = Math.round(data.offsets.popper.top);
  
          // if gpuAcceleration is set to true and transform is supported, we use `translate3d` to apply the position to the popper
          // we automatically use the supported prefixed version if needed
          var prefixedProperty;
          if (this._options.gpuAcceleration && (prefixedProperty = getSupportedPropertyName('transform'))) {
              styles[prefixedProperty] = 'translate3d(' + left + 'px, ' + top + 'px, 0)';
              styles.top = 0;
              styles.left = 0;
          }
          // othwerise, we use the standard `left` and `top` properties
          else {
              styles.left = left;
              styles.top = top;
          }
  
          // any property present in `data.styles` will be applied to the popper,
          // in this way we can make the 3rd party modifiers add custom styles to it
          // Be aware, modifiers could override the properties defined in the previous
          // lines of this modifier!
          Object.assign(styles, data.styles);
  
          setStyle(this._popper, styles);
  
          // set an attribute which will be useful to style the tooltip (use it to properly position its arrow)
          // NOTE: 1 DOM access here
          this._popper.setAttribute('x-placement', data.placement);
  
          // if the arrow modifier is required and the arrow style has been computed, apply the arrow style
          if (this.isModifierRequired(this.modifiers.applyStyle, this.modifiers.arrow) && data.offsets.arrow) {
              setStyle(data.arrowElement, data.offsets.arrow);
          }
  
          return data;
      };
  
      /**
       * Modifier used to shift the popper on the start or end of its reference element side
       * @method
       * @memberof Popper.modifiers
       * @argument {Object} data - The data object generated by `update` method
       * @returns {Object} The data object, properly modified
       */
      Popper.prototype.modifiers.shift = function (data) {
          var placement = data.placement;
          var basePlacement = placement.split('-')[0];
          var shiftVariation = placement.split('-')[1];
  
          // if shift shiftVariation is specified, run the modifier
          if (shiftVariation) {
              var reference = data.offsets.reference;
              var popper = getPopperClientRect(data.offsets.popper);
  
              var shiftOffsets = {
                  y: {
                      start: {top: reference.top},
                      end: {top: reference.top + reference.height - popper.height}
                  },
                  x: {
                      start: {left: reference.left},
                      end: {left: reference.left + reference.width - popper.width}
                  }
              };
  
              var axis = ['bottom', 'top'].indexOf(basePlacement) !== -1 ? 'x' : 'y';
  
              data.offsets.popper = Object.assign(popper, shiftOffsets[axis][shiftVariation]);
          }
  
          return data;
      };
  
      /**
       * Modifier used to make sure the popper does not overflows from it's boundaries
       * @method
       * @memberof Popper.modifiers
       * @argument {Object} data - The data object generated by `update` method
       * @returns {Object} The data object, properly modified
       */
      Popper.prototype.modifiers.preventOverflow = function (data) {
          var order = this._options.preventOverflowOrder;
          var popper = getPopperClientRect(data.offsets.popper);
  
          var check = {
              left: function left() {
                  var left = popper.left;
                  if (popper.left < data.boundaries.left) {
                      left = Math.max(popper.left, data.boundaries.left);
                  }
                  return {left: left};
              },
              right: function right() {
                  var left = popper.left;
                  if (popper.right > data.boundaries.right) {
                      left = Math.min(popper.left, data.boundaries.right - popper.width);
                  }
                  return {left: left};
              },
              top: function top() {
                  var top = popper.top;
                  if (popper.top < data.boundaries.top) {
                      top = Math.max(popper.top, data.boundaries.top);
                  }
                  return {top: top};
              },
              bottom: function bottom() {
                  var top = popper.top;
                  if (popper.bottom > data.boundaries.bottom) {
                      top = Math.min(popper.top, data.boundaries.bottom - popper.height);
                  }
                  return {top: top};
              }
          };
  
          order.forEach(function (direction) {
              data.offsets.popper = Object.assign(popper, check[direction]());
          });
  
          return data;
      };
  
      /**
       * Modifier used to make sure the popper is always near its reference
       * @method
       * @memberof Popper.modifiers
       * @argument {Object} data - The data object generated by _update method
       * @returns {Object} The data object, properly modified
       */
      Popper.prototype.modifiers.keepTogether = function (data) {
          var popper = getPopperClientRect(data.offsets.popper);
          var reference = data.offsets.reference;
          var f = Math.floor;
  
          if (popper.right < f(reference.left)) {
              data.offsets.popper.left = f(reference.left) - popper.width;
          }
          if (popper.left > f(reference.right)) {
              data.offsets.popper.left = f(reference.right);
          }
          if (popper.bottom < f(reference.top)) {
              data.offsets.popper.top = f(reference.top) - popper.height;
          }
          if (popper.top > f(reference.bottom)) {
              data.offsets.popper.top = f(reference.bottom);
          }
  
          return data;
      };
  
      /**
       * Modifier used to flip the placement of the popper when the latter is starting overlapping its reference element.
       * Requires the `preventOverflow` modifier before it in order to work.
       * **NOTE:** This modifier will run all its previous modifiers everytime it tries to flip the popper!
       * @method
       * @memberof Popper.modifiers
       * @argument {Object} data - The data object generated by _update method
       * @returns {Object} The data object, properly modified
       */
      Popper.prototype.modifiers.flip = function (data) {
          // check if preventOverflow is in the list of modifiers before the flip modifier.
          // otherwise flip would not work as expected.
          if (!this.isModifierRequired(this.modifiers.flip, this.modifiers.preventOverflow)) {
              console.warn('WARNING: preventOverflow modifier is required by flip modifier in order to work, be sure to include it before flip!');
              return data;
          }
  
          if (data.flipped && data.placement === data._originalPlacement) {
              // seems like flip is trying to loop, probably there's not enough space on any of the flippable sides
              return data;
          }
  
          var placement = data.placement.split('-')[0];
          var placementOpposite = getOppositePlacement(placement);
          var variation = data.placement.split('-')[1] || '';
  
          var flipOrder = [];
          if (this._options.flipBehavior === 'flip') {
              flipOrder = [placement, placementOpposite];
          } else {
              flipOrder = this._options.flipBehavior;
          }
  
          flipOrder.forEach(function (step, index) {
              if (placement !== step || flipOrder.length === index + 1) {
                  return;
              }
  
              placement = data.placement.split('-')[0];
              placementOpposite = getOppositePlacement(placement);
  
              var popperOffsets = getPopperClientRect(data.offsets.popper);
  
              // this boolean is used to distinguish right and bottom from top and left
              // they need different computations to get flipped
              var a = ['right', 'bottom'].indexOf(placement) !== -1;
  
              // using Math.floor because the reference offsets may contain decimals we are not going to consider here
              if (a && Math.floor(data.offsets.reference[placement]) > Math.floor(popperOffsets[placementOpposite]) || !a && Math.floor(data.offsets.reference[placement]) < Math.floor(popperOffsets[placementOpposite])) {
                  // we'll use this boolean to detect any flip loop
                  data.flipped = true;
                  data.placement = flipOrder[index + 1];
                  if (variation) {
                      data.placement += '-' + variation;
                  }
                  data.offsets.popper = this._getOffsets(this._popper, this._reference, data.placement).popper;
  
                  data = this.runModifiers(data, this._options.modifiers, this._flip);
              }
          }.bind(this));
          return data;
      };
  
      /**
       * Modifier used to add an offset to the popper, useful if you more granularity positioning your popper.
       * The offsets will shift the popper on the side of its reference element.
       * @method
       * @memberof Popper.modifiers
       * @argument {Object} data - The data object generated by _update method
       * @returns {Object} The data object, properly modified
       */
      Popper.prototype.modifiers.offset = function (data) {
          var offset = this._options.offset;
          var popper = data.offsets.popper;
  
          if (data.placement.indexOf('left') !== -1) {
              popper.top -= offset;
          } else if (data.placement.indexOf('right') !== -1) {
              popper.top += offset;
          } else if (data.placement.indexOf('top') !== -1) {
              popper.left -= offset;
          } else if (data.placement.indexOf('bottom') !== -1) {
              popper.left += offset;
          }
          return data;
      };
  
      /**
       * Modifier used to move the arrows on the edge of the popper to make sure them are always between the popper and the reference element
       * It will use the CSS outer size of the arrow element to know how many pixels of conjuction are needed
       * @method
       * @memberof Popper.modifiers
       * @argument {Object} data - The data object generated by _update method
       * @returns {Object} The data object, properly modified
       */
      Popper.prototype.modifiers.arrow = function (data) {
          var arrow = this._options.arrowElement;
          var arrowOffset = this._options.arrowOffset;
  
          // if the arrowElement is a string, suppose it's a CSS selector
          if (typeof arrow === 'string') {
              arrow = this._popper.querySelector(arrow);
          }
  
          // if arrow element is not found, don't run the modifier
          if (!arrow) {
              return data;
          }
  
          // the arrow element must be child of its popper
          if (!this._popper.contains(arrow)) {
              console.warn('WARNING: `arrowElement` must be child of its popper element!');
              return data;
          }
  
          // arrow depends on keepTogether in order to work
          if (!this.isModifierRequired(this.modifiers.arrow, this.modifiers.keepTogether)) {
              console.warn('WARNING: keepTogether modifier is required by arrow modifier in order to work, be sure to include it before arrow!');
              return data;
          }
  
          var arrowStyle = {};
          var placement = data.placement.split('-')[0];
          var popper = getPopperClientRect(data.offsets.popper);
          var reference = data.offsets.reference;
          var isVertical = ['left', 'right'].indexOf(placement) !== -1;
  
          var len = isVertical ? 'height' : 'width';
          var side = isVertical ? 'top' : 'left';
          var translate = isVertical ? 'translateY' : 'translateX';
          var altSide = isVertical ? 'left' : 'top';
          var opSide = isVertical ? 'bottom' : 'right';
          var arrowSize = getOuterSizes(arrow)[len];
  
          //
          // extends keepTogether behavior making sure the popper and its reference have enough pixels in conjuction
          //
  
          // top/left side
          if (reference[opSide] - arrowSize < popper[side]) {
              data.offsets.popper[side] -= popper[side] - (reference[opSide] - arrowSize);
          }
          // bottom/right side
          if (reference[side] + arrowSize > popper[opSide]) {
              data.offsets.popper[side] += reference[side] + arrowSize - popper[opSide];
          }
  
          // compute center of the popper
          var center = reference[side] + (arrowOffset || reference[len] / 2 - arrowSize / 2);
  
          var sideValue = center - popper[side];
  
          // prevent arrow from being placed not contiguously to its popper
          sideValue = Math.max(Math.min(popper[len] - arrowSize - 8, sideValue), 8);
          arrowStyle[side] = sideValue;
          arrowStyle[altSide] = ''; // make sure to remove any old style from the arrow
  
          data.offsets.arrow = arrowStyle;
          data.arrowElement = arrow;
  
          return data;
      };
  
      //
      // Helpers
      //
  
      /**
       * Get the outer sizes of the given element (offset size + margins)
       * @function
       * @ignore
       * @argument {Element} element
       * @returns {Object} object containing width and height properties
       */
      function getOuterSizes(element) {
          // NOTE: 1 DOM access here
          var _display = element.style.display,
              _visibility = element.style.visibility;
          element.style.display = 'block';
          element.style.visibility = 'hidden';
          var calcWidthToForceRepaint = element.offsetWidth;
  
          // original method
          var styles = root.getComputedStyle(element);
          var x = parseFloat(styles.marginTop) + parseFloat(styles.marginBottom);
          var y = parseFloat(styles.marginLeft) + parseFloat(styles.marginRight);
          var result = {width: element.offsetWidth + y, height: element.offsetHeight + x};
  
          // reset element styles
          element.style.display = _display;
          element.style.visibility = _visibility;
          return result;
      }
  
      /**
       * Get the opposite placement of the given one/
       * @function
       * @ignore
       * @argument {String} placement
       * @returns {String} flipped placement
       */
      function getOppositePlacement(placement) {
          var hash = {left: 'right', right: 'left', bottom: 'top', top: 'bottom'};
          return placement.replace(/left|right|bottom|top/g, function (matched) {
              return hash[matched];
          });
      }
  
      /**
       * Given the popper offsets, generate an output similar to getBoundingClientRect
       * @function
       * @ignore
       * @argument {Object} popperOffsets
       * @returns {Object} ClientRect like output
       */
      function getPopperClientRect(popperOffsets) {
          var offsets = Object.assign({}, popperOffsets);
          offsets.right = offsets.left + offsets.width;
          offsets.bottom = offsets.top + offsets.height;
          return offsets;
      }
  
      /**
       * Given an array and the key to find, returns its index
       * @function
       * @ignore
       * @argument {Array} arr
       * @argument keyToFind
       * @returns index or null
       */
      function getArrayKeyIndex(arr, keyToFind) {
          var i = 0,
              key;
          for (key in arr) {
              if (arr[key] === keyToFind) {
                  return i;
              }
              i++;
          }
          return null;
      }
  
      /**
       * Get CSS computed property of the given element
       * @function
       * @ignore
       * @argument {Eement} element
       * @argument {String} property
       */
      function getStyleComputedProperty(element, property) {
          // NOTE: 1 DOM access here
          var css = root.getComputedStyle(element, null);
          return css[property];
      }
  
      /**
       * Returns the offset parent of the given element
       * @function
       * @ignore
       * @argument {Element} element
       * @returns {Element} offset parent
       */
      function getOffsetParent(element) {
          // NOTE: 1 DOM access here
          var offsetParent = element.offsetParent;
          return offsetParent === root.document.body || !offsetParent ? root.document.documentElement : offsetParent;
      }
  
      /**
       * Returns the scrolling parent of the given element
       * @function
       * @ignore
       * @argument {Element} element
       * @returns {Element} offset parent
       */
      function getScrollParent(element) {
          var parent = element.parentNode;
  
          if (!parent) {
              return element;
          }
  
          if (parent === root.document) {
              // Firefox puts the scrollTOp value on `documentElement` instead of `body`, we then check which of them is
              // greater than 0 and return the proper element
              if (root.document.body.scrollTop || root.document.body.scrollLeft) {
                  return root.document.body;
              } else {
                  return root.document.documentElement;
              }
          }
  
          // Firefox want us to check `-x` and `-y` variations as well
          if (['scroll', 'auto'].indexOf(getStyleComputedProperty(parent, 'overflow')) !== -1 || ['scroll', 'auto'].indexOf(getStyleComputedProperty(parent, 'overflow-x')) !== -1 || ['scroll', 'auto'].indexOf(getStyleComputedProperty(parent, 'overflow-y')) !== -1) {
              // If the detected scrollParent is body, we perform an additional check on its parentNode
              // in this way we'll get body if the browser is Chrome-ish, or documentElement otherwise
              // fixes issue #65
              return parent;
          }
          return getScrollParent(element.parentNode);
      }
  
      /**
       * Check if the given element is fixed or is inside a fixed parent
       * @function
       * @ignore
       * @argument {Element} element
       * @argument {Element} customContainer
       * @returns {Boolean} answer to "isFixed?"
       */
      function isFixed(element) {
          if (element === root.document.body) {
              return false;
          }
          if (getStyleComputedProperty(element, 'position') === 'fixed') {
              return true;
          }
          return element.parentNode ? isFixed(element.parentNode) : element;
      }
  
      /**
       * Set the style to the given popper
       * @function
       * @ignore
       * @argument {Element} element - Element to apply the style to
       * @argument {Object} styles - Object with a list of properties and values which will be applied to the element
       */
      function setStyle(element, styles) {
          function is_numeric(n) {
              return n !== '' && !isNaN(parseFloat(n)) && isFinite(n);
          }
  
          Object.keys(styles).forEach(function (prop) {
              var unit = '';
              // add unit if the value is numeric and is one of the following
              if (['width', 'height', 'top', 'right', 'bottom', 'left'].indexOf(prop) !== -1 && is_numeric(styles[prop])) {
                  unit = 'px';
              }
              element.style[prop] = styles[prop] + unit;
          });
      }
  
      /**
       * Check if the given variable is a function
       * @function
       * @ignore
       * @argument {*} functionToCheck - variable to check
       * @returns {Boolean} answer to: is a function?
       */
      function isFunction(functionToCheck) {
          var getType = {};
          return functionToCheck && getType.toString.call(functionToCheck) === '[object Function]';
      }
  
      /**
       * Get the position of the given element, relative to its offset parent
       * @function
       * @ignore
       * @param {Element} element
       * @return {Object} position - Coordinates of the element and its `scrollTop`
       */
      function getOffsetRect(element) {
          var elementRect = {
              width: element.offsetWidth,
              height: element.offsetHeight,
              left: element.offsetLeft,
              top: element.offsetTop
          };
  
          elementRect.right = elementRect.left + elementRect.width;
          elementRect.bottom = elementRect.top + elementRect.height;
  
          // position
          return elementRect;
      }
  
      /**
       * Get bounding client rect of given element
       * @function
       * @ignore
       * @param {HTMLElement} element
       * @return {Object} client rect
       */
      function getBoundingClientRect(element) {
          var rect = element.getBoundingClientRect();
  
          // whether the IE version is lower than 11
          var isIE = navigator.userAgent.indexOf("MSIE") != -1;
  
          // fix ie document bounding top always 0 bug
          var rectTop = isIE && element.tagName === 'HTML' ? -element.scrollTop : rect.top;
  
          return {
              left: rect.left,
              top: rectTop,
              right: rect.right,
              bottom: rect.bottom,
              width: rect.right - rect.left,
              height: rect.bottom - rectTop
          };
      }
  
      /**
       * Given an element and one of its parents, return the offset
       * @function
       * @ignore
       * @param {HTMLElement} element
       * @param {HTMLElement} parent
       * @return {Object} rect
       */
      function getOffsetRectRelativeToCustomParent(element, parent, fixed) {
          var elementRect = getBoundingClientRect(element);
          var parentRect = getBoundingClientRect(parent);
  
          if (fixed) {
              var scrollParent = getScrollParent(parent);
              parentRect.top += scrollParent.scrollTop;
              parentRect.bottom += scrollParent.scrollTop;
              parentRect.left += scrollParent.scrollLeft;
              parentRect.right += scrollParent.scrollLeft;
          }
  
          var rect = {
              top: elementRect.top - parentRect.top,
              left: elementRect.left - parentRect.left,
              bottom: elementRect.top - parentRect.top + elementRect.height,
              right: elementRect.left - parentRect.left + elementRect.width,
              width: elementRect.width,
              height: elementRect.height
          };
          return rect;
      }
  
      /**
       * Get the prefixed supported property name
       * @function
       * @ignore
       * @argument {String} property (camelCase)
       * @returns {String} prefixed property (camelCase)
       */
      function getSupportedPropertyName(property) {
          var prefixes = ['', 'ms', 'webkit', 'moz', 'o'];
  
          for (var i = 0; i < prefixes.length; i++) {
              var toCheck = prefixes[i] ? prefixes[i] + property.charAt(0).toUpperCase() + property.slice(1) : property;
              if (typeof root.document.body.style[toCheck] !== 'undefined') {
                  return toCheck;
              }
          }
          return null;
      }
  
      /**
       * The Object.assign() method is used to copy the values of all enumerable own properties from one or more source
       * objects to a target object. It will return the target object.
       * This polyfill doesn't support symbol properties, since ES5 doesn't have symbols anyway
       * Source: https://developer.mozilla.org/en/docs/Web/JavaScript/Reference/Global_Objects/Object/assign
       * @function
       * @ignore
       */
      if (!Object.assign) {
          Object.defineProperty(Object, 'assign', {
              enumerable: false,
              configurable: true,
              writable: true,
              value: function value(target) {
                  if (target === undefined || target === null) {
                      throw new TypeError('Cannot convert first argument to object');
                  }
  
                  var to = Object(target);
                  for (var i = 1; i < arguments.length; i++) {
                      var nextSource = arguments[i];
                      if (nextSource === undefined || nextSource === null) {
                          continue;
                      }
                      nextSource = Object(nextSource);
  
                      var keysArray = Object.keys(nextSource);
                      for (var nextIndex = 0, len = keysArray.length; nextIndex < len; nextIndex++) {
                          var nextKey = keysArray[nextIndex];
                          var desc = Object.getOwnPropertyDescriptor(nextSource, nextKey);
                          if (desc !== undefined && desc.enumerable) {
                              to[nextKey] = nextSource[nextKey];
                          }
                      }
                  }
                  return to;
              }
          });
      }
  
      return Popper;
  });