GTK: create a colored regular button

Answer 1

Here's a little example:

import gtk

win = gtk.Window()
win.connect("destroy", gtk.main_quit)

btn = gtk.Button("test")

#make a gdk.color for red
map = btn.get_colormap() 
color = map.alloc_color("red")

#copy the current style and replace the background
style = btn.get_style().copy()
style.bg[gtk.STATE_NORMAL] = color

#set the button's style to the one you created
btn.set_style(style)

win.add(btn)
win.show_all()

gtk.main()