Yes, we all need to start somewhere. :-)
Your CSS validates, but your HTML does not. I'm not sure what the problem is exactly, but I can tell you that it will probably be fixed, or at least be a lot easier to troubleshoot, if you get rid of the table-based design. Also, divs aren't allowed in tables, only spans. If you learn the difference between inline and block elements then you will understand why. Then you can use block elements instead of <br>.
I'm afraid you probably aren't going to get a quick fix for this. Using tables for your layout creates all sorts of unpredictable problems like this one and they are very strongly discouraged, so you really need to go back to the drawing board and make a layout without tables. Hope that helps, at least.