Adding custom style for special pages

Hi!

I had the same problem a few days ago and I also came to the conclusion that it is not possible to change the registration of mediawiki.special.preferences.

I solved this by adding and adjusting styles for those elements, which I want to look different to the skin's CSS files. They overwrite what is defined in mediawiki.special.preferences. You might have to use "!important" in order to make your CSS overwrite what comes from mediawiki.special.preferences, if your rules would otherwise not be special enough.