This is a really interesting concept. I really liked the animation that played when you opened the door and treasure chest after each level. One minor thing that I kept running into was that the audio for whichever note block I clicked would overlap with the audio from pressing the play button to hear what I'm trying to match, so I think it'd be nice to stop the first audio when clicking the play button so they don't overlap. Not a big deal at all tho! Nice work!