cube

HTML

<div class="block">
    <div class="part"></div>
</div>

CSS

div
{
    position:absolute;
    -webkit-transition: all 0.3s ease-out;
}
.block
{
    top:50px;
    left:50px;
    width:80px;
    height:40px;
    background:#fc0;
    
}
.block .part
{
    background:#444;
    width:inherit;
    height:inherit;
    -webkit-transform: translate3d(0,0,50px);
}
.block:hover .part
{
    -webkit-transform: translate3d(10px,10px,20px);
}