Vertical & Horizontal Centering of a block

by alekskorovin

HTML

<div class="content"></div>

CSS

.content { 
    bottom: 0; 
    left: 0; 
    right: 0; 
    top: 0; 
    margin: auto; /* This Margin makes a trick */
    position: absolute; 
    width: 50%; 
    height: 50%; 
    background: red;
}