doble centrado margin auto

by kseso

HTML

<div id="center">
    ¡Magia! <a href='http://jsfiddle.net/mBBJM/'>Aquí el jsfiddle original</a>
</div>

CSS

#center {
position: absolute;
top:0;
left:0;
right:0;
bottom:0;
margin: auto;
background: #83C24A;
height: 100px;
width: 200px;
box-shadow: 0 0 4px rgba(0,0,0,.3);
}
html {background: #DBDBDB}