... was that it is not as easy as it sounds first. While formating elements using inline CSS is quite easy, using nested CSS classes is quite complicate. Finding that some browsers have implementation bugs or different understanding of a standard makes things even more tricky.
I found that Opera browser and mozilla seem to have a good implementation while IE has some caveats.
Overall CSS has everything it needs to build a complex page without the need to use any tables! This means that the page is displayed correct on different screen resolutions!
If you want to make a deep dive into Cascaded Style Sheets by your own you may want to read this book: