Keyframe

#box {
  -webkit-animation: my-animation 5s infinite; /* Safari 4+ */
  -moz-animation:    my-animation 5s infinite; /* Fx 5+ */
  -o-animation:      my-animation 5s infinite; /* Opera 12+ */
  animation:         my-animation 5s infinite; /* IE 10+, Fx 29+ */
}

@keyframes my-animation {
 0% {
   transform: translate(0px, 0px);
 }
 25% {
   transform: translate(30px, 15px);
 }
 50% {
   transform: translate(60px, 30px);
 }
 /* … */
 100% {
   transform: translate(300px, 150px);
 }
}