How to change background color of window of specific program?

I use Evince to read pdf files but I’d like to change the background color better for my eyes. Unfortunately, Evince has no this possibility. Maybe there is a possibility in FVWM to change the background color for Evince’s window only?

Maybe I will be proven wrong by other posters, but I assume the background color in a running program is this program’s (in this case, Evince’s) responsibility. I do not think FVWM (or any other window manager) could alter this.

NB: as an alternative to Evince, did you check Zathura? It is lightweight and fast, and it allows you to customize foreground and background colors.

Thank you for your reply. I guess you are right. I use mupdf-x11 as an alternative. But, to make the highlight of the text or comments, the evince has minimal tools which I need. There mupdf-gl has this kind of tool but it is very uncomfortable to make the highlight. I tried to use Zathura, but mupdf is more comfortable for me. The question about a background in Evince is very old, but till now is not been solved. By the way, Zathura can make highlights and comments in pdf? If yes, is it simple to use this tool?

I don’t think Zathura deals with annotations… This is a real bummer, as I find Zathura excellent in all other respects. What I do is to use Zathura as may daily driver, and try another tool (Evince? Google drive) when needed :-(

This has nothing to do with fvwm, as fvwm has no control over the application choosing its own window colours.

I saw on the Internet that it is possible to compile Evince and change a little in the source to fix specific color backgrounds. Will try and parallelly will ask them to improve evince in this way.

Evince is a gtk3 (maybe 4) app, you will need to set the gtk3 theme for that.

I think it is impossible to set a specific theme for a specific program. gtk theme is for the whole system.

somiaj’s idea of using gtk3 theming is great.

Gtk theming depend on one big gtk.css file. Inside this file, one can certainly add theme elements that are specific to a given app (e.g., .thunar toolbar, .gedit-document-panel, etc.). Finding out the right element names and their CSS hierarchies is a PITA though…

Yes, I found too the possibility to apply a specific theme for specific programs, but the theme is included icons and part of the window. I remember I changed the thickness of the cursor. But I did not find how to change the background of the window.