Referencing external stylesheets in Wordpress

How to Protect CSS Mods for ANY WordPress Theme

Almost exactly what I was looking for -- thank you!

Unfortunately, I still don't know how to prevent WordPress from stripping class tags from my <pre> links, when I post from MarsEdit.

Update

The MarsEdit forums provide a solution:

the "class" attribute is not allowed by default with the "kses.php" file in WordPress. I guess after editing that file and allowing class as an allowed attribute, it is working fine.

Indeed, it is:

#!/usr/bin/env python3.0

for i in range(10): print("Mon Dieux, it works!")