A CodePen by Mike King. Twisty - Simple square CSS animation inspired by mr. div's gif animations (http://mrdiv.tumblr.com/)

index.html

<div class="container">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
<div class="square">
<div class="square black">
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>
</div>

script.js

/*
 * Webkit browsers still have the smoothest rendering 
 * for CSS rotation animations, so this pen is best 
 * viewed in Chrome or Safari.
 */

style.css

html{
  background: black;
  height: 100%;
  position: relative;
}

.container{
  height: 300px;
  width: 300px;
  position: absolute;
  top: 50%;
  left: 50%;
  margin: -150px 0 0 -150px;
}

.square{
  height: 94%;
  width: 94%;
  background: white;
  position: absolute;
  top: 50%;
  left: 50%;
  margin: -47% 0 0 -47%;
}

.black{ 
  background: black;  
  animation: rotate 10s infinite linear; 
}

@keyframes rotate{
  0%{ transform: rotate(0deg); }
	100%{ transform: rotate(360deg); }	
}