It doesn't work on IE9 either. Thus we see the flaw in designing programs in html/CSS there is no guarantee that what you wrote is what will happen/appear on a browser. Even worse than an untyped language. A programming language that has the programmer "suggest" commands rather than demand them.
Snarkiness aside, I feel the pain behind your complaint. That's one reason I think CSS can be harder than actual programming: you have all these unknowns and contingencies to manage.