Hacker News Reader

Unfortunately, this will make colors look off on OS X. "highlight" color is different from the focus color on OS X.

Hardcoding colors for different OS-s might be more reliable.

Oh, didn't know. You could even force highlight colors, by explicitly setting border or outline colors.

And different OS themes... And updating the list every time they change...

I doubt you can detect an OS theme with Javascript or CSS.

You can actually partially detect it with Firefox.