It's not the best but I had it lying around so it will do for the meantime At the bottom of the page on the left hand side you'll see a "Style Choser" with the "Default Style" selected. Just click that and select Dark Style. Or click this link http://www.bad-dragon-chat.com/index.php?misc/style&style_id=3
Ok well since you guys actually seem to like it, ive made it the default style. The light vanilla XenForo style is still available if you want to use it http://www.bad-dragon-chat.com/index.php?misc/style&style_id=1