bbPress.org

Hi, totally now to this and having trouble, I need to change the colour of the forum on my site to black background with white text. I can change the text using suffusion options but this changes all text on the site. For some reason I really can not change the forum background colour. I used http://bbpress.org/forums/topic/change-forum-color/#post-100130 to help me with editing the .css file but nothing seems to have changed!

my forum is at http://antaresscorpions.co.uk/?post_type=forum At the moment we have added a red colour just so the text can be seen on both pages and forums.

Thanks for your help!

Regards