There may be a couple of tricks that might help.

• Consider embedding CSS into the content instead of using an external stylesheet (which shouldn't be too difficult as you're using PHP).

  (Update: ichimunki raises a good point. Sadly, Netscape 4.7 has a bug regarding linked stylesheets. This is only one reason why I occasionally rant about non-compliant browsers.)

• Make sure you define rules for <TD>, <TH>, and <TR>.

• Make sure you use and close your <P> tags.

Note sure if you've seen this site, but it contains a lot of CSS related information, including a page documenting many of the most egregious problems.

Hope this helps...

--f

P.S. As far using CSS and cookies go, I'm with Blue: Go for it.

My own bias would be against embedding style information into the HTML document unless absolutely necessary to assist the user agent in displaying the information (i.e. layout is integral to the information being displayed). Usually this is not the case. Putting the CSS into its own document makes the original document smaller, and heightens awareness that style is not content on the part of the designer.

Actually, If you EVER close a P tag, you need to close them all, I've had better results never closing them. Also, I've learned not to mix inline style with external stylesheets since you can't ever tell what will happen when you do. All major browsers seem to have one issue or another with mixing inline and external.

--
$you = new YOU;
honk() if $you->love(perl)

Unless you're like me with aspirations towards XHTML-compliance, then closing all of them is somewhat mandatory. :)