How do I make the vB 'editors' be dark/black?

[BirdOPrey5]

I have a custom dark style but the editors (new message/reply and quick reply / PM's, etc...) are all white backgrounds with black text just like on vbulletin.org and my other 'white' styles. I've seen forums where the editor is dark or black with white or grey text- how do I do that? I take it I need some css somewhere but I haven't figured it out yet.