[Foy]

Yay Opera!

Also, if you're really using >= 256 classes in your CSS you may have more systemic problems than just cross-brwoser compatibility.

[duaneb]

What base does Opera use for specificity?

[rplnt]

That's the sad thing about closed source software. Their implementation might be drastically different. I think they should write a blog post or at least a comment here about it though, I'm going to bug them now.

[lastorset]

We use base 24, actually, but since we truncate before concatenating, we behave as expected here, unlike Gecko/WebKit. Obviously, a different TC that depends on one selector having more class names than another ("c" in CSS 2.1 6.4.3) will fail in Opera; it passes in GeckKit. See attachment at http://lists.w3.org/Archives/Public/www-style/2012Aug/0493.h... for an illustration.

[lastorset]

Oops, should be base 25, obvs.

[StavrosK]

Probably a large one.