Why CSS sucks?
CSS is separated from reality, so it sucks.
The CSS recommendation makers simply don't really understand what web designers need.
For example, open a shiny colorful tour book. I bet every photo inside has a shadow. Well, make a shadow via CSS is a complicated work still.
A second example, look at the road signs, they have round corners. Look at your windows XP windows, they have round corners. There are round corners all around OS X. Look at my car windows, they have effectively round corners. But we don't get round corner in CSS.
So CSS sucks.