dirntknow

You can't start a class name with numbers, it just won't work.
 
I don't know exactly why it's disallowed or incompatible, but it just is.
 
You need to start with a letter, so like n450 should work.
 

<li class="n<?php echo $row_rsProfiles['Category']; ?>">some text here...</li>

Learn the basics, clean css based pages that display in more than just the browser and monitor you have. I found some great tutorials on adobe.com for dreamweaver and also a couple of books to help me along the css route. As my web design knowledge is constantly increasing i'm avoiding publishing any site for public consumption til I'm alot nearer to what I want to achieve. When designing punctuation and spelling is not something you can get 'almost right', code doesn't deal well with spelling mistakes so make sure you're up to scratch with that.
Personally, I think your goals are pretty wild for a first site but go on, prove me wrong...