How to change the colour for the repeat button in the button spinner for date time picker.

[Hazakura0210]

Basically I tried to change the color for the repeat button in the button spinner. But it cannot be changed even though I tried to put the styling and themes inside my own App.xaml. When I declare the styling for the button spinner it doesn't change anything, however if I declare a button chrome it can change the border thickness of both the button chrome itself and the repeat button, but when I tried to change the background it only changed for the button chrome and not the repeat button. So I'm wondering is there a way to change the color for the repeat button, as I have tried for a few days and has no direction.