docs: function (cssClasspath) {
              var prefixClass = this.__prefixes[cssClasspath];
              if (!prefixClass) {
                  prefixClass = this.__PREFIX + this.__NEXT_PREFIX_INDEX;
                  this.__NEXT_PREFIX_INDEX += 1;
  
                  this.__prefixes[cssClasspath] = prefixClass;
              }
  
              return prefixClass;
          }