code: function(el) {
      var pos = {
        left: 0,
        top: 0,
        width: 0,
        height: 0
      };
      if (el.getBoundingClientRect) {
        var elRect = el.getBoundingClientRect();
        var pageXOffset = _window.pageXOffset;
        var pageYOffset = _window.pageYOffset;
        var leftBorderWidth = _document.documentElement.clientLeft || 0;
        var topBorderWidth = _document.documentElement.clientTop || 0;
        var leftBodyOffset = 0;
        var topBodyOffset = 0;
        if (_getStyle(_document.body, "position") === "relative") {
          var bodyRect = _document.body.getBoundingClientRect();
          var htmlRect = _document.documentElement.getBoundingClientRect();
          leftBodyOffset = bodyRect.left - htmlRect.left || 0;
          topBodyOffset = bodyRect.top - htmlRect.top || 0;
        }
        pos.left = elRect.left + pageXOffset - leftBorderWidth - leftBodyOffset;
        pos.top = elRect.top + pageYOffset - topBorderWidth - topBodyOffset;
        pos.width = "width" in elRect ? elRect.width : elRect.right - elRect.left;
        pos.height = "height" in elRect ? elRect.height : elRect.bottom - elRect.top;
      }
      return pos;
    }
docs: Get the absolutely positioned coordinates of a DOM element.
  
  @returns Object containing the element's position, width, and height.
  @private