At the moment, you can choose between light or dark which is awesome. It would be more awesome if it could switch to dark during night etc so I don't need to manually switch it. Thanks.
If it's about luminosity and in general, I'd recommand you to try the absolutely free and fantastic f.lux
https://justgetflux.com/
If you're 16/24h on your PC or working at night, it's an eyes saver - and after some time you'll eve forget you've installed it, it's magic.
HTH.
These days you don't need flux, it's included in modern operating system's night mode. Thanks for sharing anyway though.