Good evening,
I'm trying to change some of the colours of my login screen in my Ubuntu 18.04. I followed some questions here on AskUbuntu, and edited my css files at /usr/share/gnome-shell/theme/gnome-shell.css (I'm using that configuration) - Specifically, I changed the values of .lockDialogGroup to a nicer dark gray.
My login screen is indeed now a nice dark gray instead of that hellish purple.
However, if I lock my computer without shutting down the machine, I still get a different purple gradient, which I haven't managed to change. I'm serching around but since I don't even know what to call this "behind-the-shield" screen, I can't find relevant results.
I suspect the login screen and the lock screen are two different managers altogether.
Here's a short mp4 video of me literally filming my screen, to make you understand which color I'm trying to change:
https://i.stack.imgur.com/VdEPP.jpg
EDIT: There seems to be a discrepancy between my first-after-boot login screen, and my login-after-locking screen.






printf 'Desktop: %s\nSession: %s\n' "$XDG_CURRENT_DESKTOP" "$GDMSESSION"into your post. as suggested here – Elder Geek Jan 14 '19 at 20:03