public CSSValue createValue(StyleKey name, LexicalUnit value) {
   if (value.getLexicalUnitType() == LexicalUnit.SAC_IDENT) {
     if (value.getStringValue().equalsIgnoreCase("none")) {
       return new CSSConstant("none");
     }
   }
   return CSSValueFactory.createNumericValue(value);
 }
 public CSSValue createValue(StyleKey name, LexicalUnit value) {
   // normalization is deferred until we compute the value.
   return CSSValueFactory.createNumericValue(value);
 }