code: function(hex, opacity) {
    let result = /^#?([a-f\d]{2})([a-f\d]{2})([a-f\d]{2})$/i.exec(hex);
    return result ? "rgba(" + parseInt(result[1], 16) + ", " + parseInt(result[2], 16) + ", " + parseInt(result[3], 16) + ", " + opacity + ")" : hex;
  }
docs: https://stackoverflow.com/questions/5623838/rgb-to-hex-and-hex-to-rgb