@keyframes slidy {
0% { left: 0%; }
32% { left: 0%; }
35% { left: -100%; }
64% { left: -100%; }
67% { left: -200%; }
97% { left: -200%; }
99% { left: -300%; }
100% { left: -300%; }
}

div#slider { overflow: hidden; }
div#slider figure img { width: 20%; float: left; }
div#slider figure { 
  position: relative;
  width: 500%;
  margin: 0;
  left: 0;
  text-align: left;
  font-size: 0;
  animation: 0s slidy infinite; 
}