@keyframes nyancat {
    0%   { background-image: url("nyancat-cat-1.gif"), url("nyancat-tail-1.gif"); }
   16.6% { background-image: url("nyancat-cat-2.gif"), url("nyancat-tail-1.gif"); }
   33.3% { background-image: url("nyancat-cat-3.gif"), url("nyancat-tail-1.gif"); }
   50%   { background-image: url("nyancat-cat-4.gif"), url("nyancat-tail-2.gif"); }
   66.6% { background-image: url("nyancat-cat-5.gif"), url("nyancat-tail-2.gif"); }
   83.3% { background-image: url("nyancat-cat-6.gif"), url("nyancat-tail-2.gif"); }
  100%   { background-image: url("nyancat-cat-1.gif"), url("nyancat-tail-1.gif"); }
}

progressbar.horizontal progress {
  background-image: url("nyancat-cat-1.gif"), url("nyancat-tail-1.gif");
  background-color: transparent;
  animation: nyancat 480ms infinite steps(6);
  background-repeat: no-repeat, repeat-x;
  background-position: 100% 50%, 0% 50%;
  background-size: 34px 21px, 16px 21px;
  border: none;
  padding: 0px 27px 0px 0px;
  background-origin: padding-box, content-box;
  margin: -3px -8px -2px -2px;
  min-height: 21px;
  text-shadow: 1px 1px white;
  color: purple;
}