Background Colour for WSYISYG
Permalinkbody#tinymce { color:#FFF !important; background-color:#000000 !important; }
but it doesnt make any difference at all, id really appreciate if anyone can help
thx

Also, that file is aggressively cached and hence often won't show you the updates unless you both clear the Concrete5 cache (via Dashboard -> Sitewide Settings), AND clear your browser cache.
Note that you should just be able to put this in the typography.css file:
body { color: #000; background-color: #fff; }
(that will give you black text on a white background -- if you want white text on a black background, switch the two color codes -- #000 is for black, #fff is for white)