Absolute Center
I did, however, make one modification for text, and that is to treat the div containing text with display:table.
The reason for this is so that we can vertically center multi-line and single-line text. If we employ the vertical centering CSS, like Stephen did, to a div with text, the text won’t ‘cheat up’ on multiple lines. The fix for this is pretty straightforward.

http://blogs.adobe.com/strack/2013/08/23/absolute-ly/