Dark background with white letters.
If it could be done it would be easier on my eyes anyway.
Tap on your account (usually your avatar picture), then your profile, then go to preferences, find the “interface” option, and pick one of the themes with “dark” in the title.
I think if you copy and paste this link it will take you there:
https://boards.straightdope.com/u/bodangus/preferences/interfaceTHANKS! It’s dark now and I like it!
Awesome, you’re welcome. 