docs: function colorConvert( percentage, option, colorValue ) {
          var color    = require( 'color' );
          var newColor = color( colorValue.trim() );
          var newValue = '';
  
          switch ( option.trim() ) {
          case 'darken':
              newValue = newColor.darken( percentage ).hexString();
              break;
  
          case 'lighten':
              newValue = newColor.lighten( percentage ).hexString();
              break;
  
          case 'rgb':
              newValue = newColor.clearer( percentage ).rgbString();
              break;
  
          default:
              return '';
          }
  
          return newValue;
      }