Just a little heads up in case you were wondering why...
a.Tab22 - This wouldn't be recognised on the DIV you had created, if it were to be written as you intended it should have been DIV.Tab22 and even then there would have been problems as the A tag (link) wasn't referenced which should then be... DIV.Tab22 A or .Tab22 A
Your css would have worked if the class were inside the A tag though <A href="#" class="Tab22">
Hope this helps.