Forum:How to add backgrounds?

Hello, just wondering how to add a background image to my wiki. If needed here's the link to my wikia, http://sonicpedia.wikia.com/wiki/SonicTheHedgehog_Wiki S_U_F 1:32, May 31, 2010 (UTC)

Thanks it worked!S_U_F 20:41, May 31, 2010 (UTC)
 * add body { background-image: url('example.jpg'); } to MediaWiki:Commons.css —Roguebfl(talk) 19:01, May 31, 2010 (UTC)
 * See also Help:Customizing Monaco/skin. -- 19:06, May 31, 2010 (UTC)