I'm not sure what's caused it but my Magento ver. 18.104.22.168 site is no longer loading the css. I didn't make any changes to the site whatsoever, one day it was fine the next it had fallen over.
All of the css looks fine and checking it out with firebug everything looks to be pointing to the right place.
My site is http://www.geckoclothing.com/ and here's what it currently looks like: