docs: function(rgb){
              var parts = rgb.match(/^rgb\((\d+),\s*(\d+),\s*(\d+)\)$/);
              var hex = (parts[1]<<16|parts[2]<<8|parts[3]).toString(16);
              return "#"+Array(6-hex.length).concat([hex]).toString().replace(/,/g, 0);
          }