This style is the minimum required to convert the regular bluish-white style to a nice dark one.
It is not a full-blown style and there may be some things missing; you may have to add/change some rules to get it where you want it.

Make sure you replace the url-prefix() at the top of the script with your own.
You can apply it to multiple sites like this:
@-moz-document
url-prefix("http://www.your-forum-domain.rocks/forum/"),
url-prefix("http://another.forum/forum/"),
domain("yet.another.forum")

announce_unread_locked_mine.gif removed because this site doesn't accept longer styles.
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