tThumbBoundsFn: function(index) {
              // See Options -> getThumbBoundsFn section of documentation free for more info
              var thumbnail = items[index].el.getElementsByTagName('img')[0], // find thumbnail
                pageYScroll = window.pageYOffset || document.documentElement.scrollTop,
                rect = thumbnail.getBoundingClientRect();

              return {
                x: rect.left,
                y: rect.top + pageYScroll,
                w: rect.width
              };