IE8 Fixes (part 2)

Three small fixes here:

* #434 - CSS tweaks: Adding fallback colors for `rgba`, and swapping `::after` for `:after`
* #435 - Enable CORS support in jQuery
* #430 - Click event handler changes
Ah, well it *was* correct in CSS2 - no more in CSS3:  http://www.w3.org/TR/selectors/#gen-content