code: function () {
                      var k = parserInput.$char('%') || parserInput.$re(/^\[?(?:[\w-]|\\(?:[A-Fa-f0-9]{1,6} ?|[^A-Fa-f0-9]))+\]?/);
                      if (k) {
                          return tree.Color.fromKeyword(k) || new(tree.Keyword)(k);
                      }
                  }
docs: A catch-all word, such as:  black border-collapse