In post #3, I put a link to the thread where brontide is maintaining a bundle of css; #1 in that thread has general info, and the download; #2 has the question how to install, and #3 has your answer...

Note that I have not tried brontide's stuff yet. I use my own stuff, and haven't got around to merging his in, so I don't know exactly how they compare for itT. Brontide has CSS for a lot of other sites, too, though; I'm not saying it's worse or anything, just that it may not look exactly like mine in the screenshot.