Thank you very much for your reply.
Unfortunately, I can't get your solution to work.
I created a .gtkrc-2.0 file and put the
style (and so on) command in it. Re-logged in and nothing had changed. The boxes were still there as before. Tried this several times.
So I added the rest of your suggestion, regarding the font colours. Again, no difference.
I have spent about 4 hours trying to get it to work, trying many things, remaking the .gtkrc-2 file countless times, but without success.
As your solution is the official one, I don't know why it doesn't work for me. The only thing I am wondering, is if it doesn't work because I am running the liveCD, and Phoenix is not installed.
Thanks again for your help.