text: 'use strict';
  
  function _interopDefault (ex) { return (ex && (typeof ex === 'object') && 'default' in ex) ? ex['default'] : ex; }
  
  var postcss = _interopDefault(require('postcss'));
  
  const mediaRegExp = /^media$/i;
  const prefersInterfaceRegExp = /\(\s*prefers-color-scheme\s*:\s*(dark|light|no-preference)\s*\)/i;
  const colorIndexByStyle = {
    dark: 48,
    light: 70,
    'no-preference': 22
  };
  
  const prefersInterfaceReplacer = ($0, style) => `(color-index: ${colorIndexByStyle[style.toLowerCase()]})`;
  
  var postcss$1 = postcss.plugin('postcss-prefers-color-scheme', opts => {
    const preserve = 'preserve' in Object(opts) ? opts.preserve : true;
    return root => {
      root.walkAtRules(mediaRegExp, atRule => {
        const params = atRule.params;
        const altParams = params.replace(prefersInterfaceRegExp, prefersInterfaceReplacer);
  
        if (params !== altParams) {
          if (preserve) {
            atRule.cloneBefore({
              params: altParams
            });
          } else {
            atRule.params = altParams;
          }
        }
      });
    };
  });
  
  module.exports = postcss$1;
  