A very cool experience!
The player control is very smooth and intuitive.
The map design felt very real for a backrooms-estique game, like some paths just NOT having a way back, so falling down may not kill you, but you sure won't survive either.
I really like the sound design and would have enjoyed the music to keep playing between restarts!
Not sure what is the cause of this, but the pixel art was glitching around a bit when going up and down.
Restarting without having to use the mouse would have rounded the experience, because you don't need the mouse for any of the other aspects of the game.
All in all, while short - which isn't bad - it's polished and complete. That's what counts!