code: function(selector, refreshCache, rawCache) {
              var i, result;
  
              if (!rules || refreshCache) {
                  CSS.refreshCache();
              }
              if (!Ext.isArray(selector)) {
                  result = rules[selector.toLowerCase()]
                  if (result && !rawCache) {
                      result = result.cssRule;
                  }
                  return result || null;
              }
              for (i = 0; i < selector.length; i++) {
                  if (rules[selector[i]]) {
                      return rawCache ? rules[selector[i].toLowerCase()] : rules[selector[i].toLowerCase()].cssRule;
                  }
              }
              return null;
          }
docs: Gets an an individual CSS rule by selector(s)
  @param {String/String[]} selector The CSS selector or an array of selectors to try. The first selector that is found is returned.
  @param {Boolean} refreshCache true to refresh the internal cache if you have recently updated any rules or added styles dynamically
  @return {CSSStyleRule} The CSS rule or null if one is not found