System accent color matching

I'd like for my client colors to match the rest of my system. I use a dynamic wallpaper service quite a lot, so my wallpaper (and by extension, accent color) change frequently.

Maybe CSS variables, or a preset theme, to pull the accent color from the system so Fluxer can change color with the rest of it.

At least on Linux, I believe this can be done through XDG Desktop Portal or DBus directly with org.freedesktop.appearance accent-color. Not sure about Windows, but I imagine it has a similar option.