I really enjoyed this! Even with the lack of animation, I loved seeing the variety in themes between all the environments, and of course the puzzle mechanics were neat too. While the music wasn't original, it did have a very nice vibe and made the game into an especially chill puzzle experience.
I'd love to see this expanded into a fuller and longer version! Having more cross-room interactions besides the keys (like the desert room's spring plant) would be particularly cool to see.
I did confused at first by the keys being color-coded since I completely missed the first 2 in the red room and so had no idea why the yellow key didn't affect the red blocks until I checked the comments, but that's really more on me (a tip somewhere would help tho).