product info CSS not working

[Guest]

I had this working fine. I was trying to get a background into the center of my product info pages. I had about 20 pages but was only working on one. I made one change to the CSS to add a class with a background image I then put the class on the html page. I have been working on this for a few days now trying many different ways to get the background to show up. The CSS was working fine, till sometime this morning then all product pages stopped reading the CSS file. I even removed the class from the CSS and the HTML but no luck. I even re-uploaded my back-up files but they still dont read the CSS file. Has anyone ever had this happen to them. I even cleared my cache thinking it may just be my PC but still no luc. Please offer some suggestions on what may have happened.

Pat