code: function (h, op) {
      if (typeof op !== "undefined") {
        h.style.opacity = op;
      }
      if (typeof h.style.opacity !== "undefined" && h.style.opacity !== "") {
        h.style.filter = "alpha(opacity=" + (h.style.opacity * 100) + ")";
      }
    }
docs: Set the opacity. If op is not passed in, this function just performs an MSIE fix.
  @param {Node} h The HTML element.
  @param {number} op The opacity value (0-1).