What I am currently looking for is a place where a global theming could be defined.
Right now, everything seems to render black on white - but what if I would like to have it the other way round (white on black)? Where could I configure such a theme?
Espruino is a JavaScript interpreter for low-power Microcontrollers. This site is both a support community for Espruino and a place to share what you are working on.
I guess that refers to the file on Github. Take a look at https://github.com/espruino/BangleApps/blob/d9d5926416566762e59b953c745f989d23c9b334/apps/setting/settings.js#L214
For the currently used theme just use g.theme. That will spit out a JSON array.