Amazing work. The graphics and game feel are of top quality. I liked the liminal environments as well. I suggest adding a timer if you made it as a speedrunning game. Also, a checkpoint system or progressive loss (players can fall or get stuck but can come out with some other ways instead of restarting the whole level) if there is only one long level. Restarting from the beginning works best for shorter levels or score-based games. Also can be more immersive if it was in full screen.
Overall, It was fun to play