Fl_Check_Button - set background color of checkmark

[holm.h...@gmail.com]

Hello,

I need to change the background of the checkmark for a Fl_Check_Button.

From documentation, I find :
The selection_color() sets the color of the checkmark. Black is default.
I however need to set the background - which is white as default.

How do I change this color ?

Best regards
Håvard Holm