gtkWidgetModifyStyle. gtkWidgetModifyBg(object, state, color = NULL)objectstatecolorNULL to undo the effect of previous calls to
of gtkWidgetModifyBg. [ allow-none ]GTK_NO_WINDOW flag set)
draw on their parent container's window and thus may not draw any
background themselves. This is the case for e.g. GtkLabel. To modify
the background of such widgets, you have to set the background color
on their parent; if you want to set the background of a rectangular
area around a label, try placing the label in a GtkEventBox widget
and setting the background color on that.