code: public static boolean isSpecialColorName(final String colorName)
      {
          for (final String name : SPECIAL_COLOR_NAMES)
          {
              if (name.equalsIgnoreCase(colorName))
              {
                  return true;
              }
          }
          return false;
      }
docs: The test is case-sensitive. It assumes the value was already converted to lower-case.
  
  @param colorName
  
  @return Whether the colorName is one of the "special" color names that are allowed as color values,
  but are not actually colors, i.e. "transparent", "inherit" or "currentcolor".