Weird glitch

Ever since starting up the game, there's this annoying gray tint on my screen and I can't find a way to get rid of it. I've tried installing ET:L, uninstalling and reinstalling the game, resetting display settings, using the windows+ctrl+shift+b shortcut, and rebooting my pc, but none have worked at all. I couldn't find anyone else on the internet who had this problem, and I am not tech savvy. Does anyone know how to actually fix this?