For those that think that black backgrounds are better for OLED displays, or simply like this kind of schemes, I have tweaked VitaminC a little bit. Credits to shalafi and this post
that saved me a lot of time.
The file that has to be uncompressed into waze/skins/default/day directory is the attached zip.
Doing so will overwrite the original VitaminC schema, so if you want to keep it, you'd better make a backup.
And if someone wants to play with it, the only difficulty is to translate hex codes into colours. The rest is almost readable text. For the hex codes, this web page is useful:
Comments and suggestions welcome. Doubts might be solved.