CSS

As a programmer, I always want to (or MUST) learn new technologies. I am doing system programming, but I need to write a web page or two from time to time (I wonder why I need to do this. I have been writing hacks to intercept Windows system calls; network device drivers and packets sniffer; to GUI program and Web pages... What have I done in my last life to deserve this? :D). Knowing how to do CSS is still cool :)