I am using the IE developer tools, so I can see specifically which .css files are being actually used when my pages are being rendered. My Portal.css page is not even referenced. The classes I put in there are never seen or used by the browser. Why is that?

Problem solved. I had a comment in the very top of the stylesheet editor that had an improper closing code - effectively turinging my css code into one big comment. Oops. I hate when that happens.

I had a very similar issue today. In my case, there was just a single extraneous character ...