It is likely your browser. What are you using? I can't see from the picture.

W3C compliance, though very good, can be a bit tough to reach some times, especially when your dealing in a CMS. We strive to reach it, but sometimes it is impossible. For instance, the code used to embed flash into a html page is not w3c compliant, so if your going to use any flash, then you can pretty much give up on making you site fully compliant. I have read about ways to make it so, but they seemed like a lot of work for something so minor. Still, I respect the W3C for all they have done. Where would we be without CSS.

Matt