Add a percentage scale to each one and a custom background picker. The two colors black & white has gotten old. Why not 70% grey or from white to light blue, green or grey on a percentage?
Add the feature to Good Lock if too late for OneUI 7.
You know you can place a color filter over your screen in various colors and ranges of transparency. Especially useful for light mode, maybe not so much for dark. You can find it in accessibility settings/vision enhancements or the icon in the quick panel (long press to get the color/transparency selection)
