Seeking Recommendation for Good CSS Reference

I am now fine tuning my DB source to produce both pdf and html.

pdf is looking pretty good but I need some CSS help and wonder if
there is one book or reference folks use, especially for the
Firefox/IE browsers.

I have "Beginning CSS Web Development" by Simon Collison but it
doesn't quite have what I need (at least it doesn't quite fit the way
my brain works).

Thanks,

-Tom

Thomas M. Browder, Jr.
Niceville, Florida
USA