#back-to-top,
#back-to-top.visible {display: none;}

#back-to-top {position: fixed;bottom: 0;right: 0;cursor: pointer;padding: 3px 17px 3px 7px;
  font: bold 14px Arial, Helvetica, sans-serif;color: #fff;background: #666 url(images/triangle-gray-up.png) no-repeat right center;}

#back-to-top.visible {display: inline;}