Nice, but I find it a bit too hard to read. On my Stylebot style, I reduced the orange to just a highlight colour. I find it pretty pleasurable to use. Feel free to take anything from it that you want: http://stylebot.me/styles/2800

Some of the selectors in the CSS are very contrived. I found it was the only way to select what I wanted in a document made of tables within tables with barely any classes.

Also, I totally feel you on this! The underlying HTML for HN is absolutely terrible.