code: CssFormatter appendColor( double color, @Nullable String hint ) {
          if( !inlineMode && hint != null ) {
              output.append( hint );
          } else {
              int argb = ColorUtils.argb( color );
              output.append( '#' );
              appendHex( argb, 6 );
          }
          return this;
      }
docs: Append a color. In inline mode it is ever a 6 digit RGB value.
  @param color the color value
  @param hint the original spelling of the color if not calculated
  @return this