<!DOCTYPE HTML>
<html reftest-zoom="1.5">
<title>Reftest, bug 1156456</title>
<style>

html, body {
  height: 100%;
}

body {
  background: white;
  perspective: 1000px;
}

div, div::before, div::after {
  width: 200px; height: 200px;
}

@keyframes HoldTransform {
  from, to {
    /* approximately rotateY(-120deg) rotateX(60deg); */
    transform: rotateY(-2.0944rad) rotateX(1.0472rad);
  }
}

div {
  position: absolute;
  top: 0; right: 0; bottom: 0; left: 0;
  margin: auto;
  transform-origin: 50% 50% 100px;
  background: #006;
  transform-style: preserve-3d;
  animation: 10s HoldTransform infinite;
}

div::before, div::after {
  position: absolute;
  top: 0; left: 0;
  content: "";
}

div::before {
  background: #00f;
  transform: translate3D(100px, 0, 100px) rotateY(90deg);
}

div::after {
  background: #00c;
  transform: translate3D(0, -100px, 100px) rotateX(90deg);
}

</style>
<div></div>