Jump to content
Not to be too cynical, but this seems like a lot of CSS for a technique that only works as fully intended on a browser with ~5% market share (depending of course on your visitor demographic).
The addition of one surrounding tag (such as a span) and the use of two images can create the same effect cross-browser.
The point about making things look the same in all browsers is of course one that can be discussed at length, but the subject matter of this article is applying a visual technique to an element on a web page in order to make it look pretty. If the technique only works for 5% of your visitors, then maybe it is not the most optimal technique to be using.