iLiad GTK+ resource file [.gtkrc]?

[yokos]

I have the problem that the default background colour of all GTK+ widgets on iLiad is "some kind of grey". This grey colour insn't very friendly to "typing refresh". You get ghosting. A pure white instead of this grey would be much better.

Yes, I can set the style "bg[state]" manually in all widgets [and this works: I tested it with calcoo (3rd screenshot)], but a central tweak would be much easier.

Q:
[1] Where are iLiad's GTK+ default values of widget styles saved?
Two interesting paths:
# /usr/share/libergtk
# /usr/share/themes
[2] Can I set a path to my own .gtkrc in the starting shell script of the app? Then the app could load the rc file with gtk_rc_parse().

screenshots:
a not released puzzle game [grey background is bad because I get ghosting all the time, I don't want to start a full screen refresh every time. I didn't set bg to white yet.]