Split HOME screen 'too dark'. 26 Sportage HEV SX

HI folks, my first foray to this Forum. I have arranged my split home screen to show the following 3 items..

MEDIA------------------PHONE----------------NAV

Here is the issue, my small NAV screen is jet black (as are the others) and I find it very difficult to see the
map. Have tried adjusting the instrument brightness, NO JOY.
Now when I touch the NAV screen it goes full screen and nice and bright and fully readable.

Question; any idea how I can keep my 'split NAV screen ''white''?

Thanks for helping out..

So far I love the car