code: public static boolean isValidColorName(final String colorName)
      {
          if (null == colorName)
          {
              return false;
          }
          final String str = colorName.toLowerCase();
  
          return (isSpecialColorName(str) || (ColorName.lookup(str) != null) || COLOR_RE.test(str));
      }
docs: Checks whether the colorName is a valid CSS color.
  This includes the "special" colors: "transparent", "inherit" or "currentcolor".
  Color names are case-insensitive.
  
  <br/><br/>
  Here are some examples of valid colors:
  "#00f", "#0f0f0f", "#00F", "#0F0F0F", "rgb(255,0,0)", "rgba(0,0,0,0)", "red",
  "rgb(100%, 0%, 0%)", "hsl(0, 100%, 50%)", "hsla(120, 100%, 50%, 1)",
  "transparent", "inherit", "currentcolor".
  
  @param colorName
  
  @return Whether the colorName is a valid CSS color.
  
  @see <a href="http://www.w3.org/TR/css3-color/">CSS Color Module Level 3</a>