z-Index behaviour on pseudo elements
You would have to give pseudo elements a negative z-index to get it to go behind it's parent, plus remove the z-index on the parent. http://jsfiddle.net/jklm313/Kq2PY/4/
div{
position:relative;
background: #000;
padding: 10px;
}
div:after{
content: '';
position: absolute;
z-index: -1; /* <= not working:( */
background: #3d3;
left: 20px;
top: 20px;
width: 30px;
height: 30px;
} <div>erferf</div>div { z-index: 1; }
div::after { z-index: -1;}