This is a high quality submission, from both a design and technical point of view. I've played some Godot games recently that have toasted my modest CPU/GPU, yet it handles these gorgeous graphics without breaking a sweat. Clearly you know what you're doing with those shaders.
I'm not great a this type of game, but I did get the first level of each colour, and had a lot of fun doing so. My only niggle, as others have mentioned, is the sensitivity of the rotation key controls. Also, as the corridors are all up/down or left/right, perhaps there is some way of getting orientation to lock at, or to gravitate towards, 0/90/180/270 degrees?
Anyway, that's just small stuff though. Great work!