From what I can see, it looks like you're good now. I don't see a background when I look at your site. Perhaps just the cache needs to be updated on your site.
Let me know if the problem persists.
I've "fixed" it by commenting it out in the CSS, but
http://amlugfaer.dkpsystem.com/adminbackgroundimage.php still has the background image that's incorrect for our site, and when I try to delete it, nothing happens. I'd like that incorrect background image removed, so that if the line accidently gets uncommented, it won't break our site.