Hi,
in your .rootrc you may put these entries:
(see also $ROOTSYS/etc/system.rootrc)
Gui.BackgroundColor: #e8e8e8
Gui.ForegroundColor: black
Gui.HighLightColor: #d0d0d0
Gui.SelectBackgroundColor: #d0d0d0
Gui.SelectForegroundColor: black
Gui.DocumentBackgroundColor: white
Gui.DocumentForegroundColor: black
Gui.TooltipBackgroundColor: LightYellow
Gui.TooltipForegroundColor: black
You are probably looking for: Gui.SelectBackgroundColor: #d0d0d0
Cheers
Otto