Adding CSS / Appgyver

Is it possible to add customs CSS in appgyver? If so, how does it work?

Yes, by editing the relevant root file.
Download the zip, edit, upload.

Basically I have to add the css in every page from the ZIP folder?
This is only working for Web app?
What about for android?

Check previous posts form this forum.

I’ve been searching but I can not find anything

If there is a style.css file in the root, you may have a chance to edit it once for all pages.
But I’m not sure react native root files contain such styling file.