CSS Secrets

Foreword

Ah, the good old days. Back in the previous millennium, we had just two CSS-capable browsers, and what they did was a fairly limited subset of a fairly limited specification, so you could fairly easily keep a complete map of what worked and what didn’t in your head. That map included the bugs in each implementation, as they had many errors and oversights, some of them verging on the comical. Heck, some bugs were so fundamental that they made the browsers’ layout behavior completely incompatible, forcing us to come up with a whole army of parser-bug-exploiting hacks just to work around the differences!

Wait a minute. The old days were horrible. Glad we’re done with all that!

Things really have gotten so much better in the last several years, CSS-wise. Browsers have, for the most part, converged on compatibility, and where they are incompatible, it’s nearly always because one browser doesn’t support a feature that another does, as opposed to both of them trying to support the same thing differently, and usually badly. The specifications have pushed capabilities forward even as they’ve added features that recreate the convoluted tricks of old in much simpler, more compact ways. CSS has far more features and far more power than ever before—but, as we all know, with great power comes great complexity. It’s not even a case of intentional complexity: when you combine enough working parts, no matter how simple each may be, interesting things can and do emerge. (For more on this ...