Pick the colour scheme: System, Light or Dark. System still follows the
device, as before; the other two hold what you choose whatever the phone
is set to, and apply to the keyboard and to the app's own screens alike.
On Android 12 and later the colours themselves are still taken from the
system's own palette, so a forced dark keyboard still matches your
wallpaper theme.

It is in Settings at the top, and on the menu page the Theme key - which
did nothing until now - walks the three in turn.
