Css validation fixes

There are still several problems, but this fixes a few.

http://jigsaw.w3.org/css-validator/validator?uri=http%3A%2F%2Fucommfairchild.unl.edu%2Fwdn_develop%2Fdebug.shtml&profile=css3&usermedium=all&warning=1&vextwarning=&lang=en