The standard focus rectangle draws as either white or black depending on the background of the widget (from what I can tell anyways)

In my application I have styled QPushButton via stylesheets to have a gradient background that is very light and requires a black focus rectangle, but Qt is drawing a white focus rectangle! If I change the background color to be solid and the darkest color of my gradient I get the black focus rectangle so I can only assume that gradient background is confusing the painter.

How can I force it to draw the focus rectangle in black?

Note that setting the style QPushButton:focus gives a completely different effect it changes the overall look of the button when it has focus and not the focus rectangle itself.