I think you have the bones (pun intended) of a really good rhythm game here. The notes did sometimes seem completely separate from the music. That could have just been a web-shenanigans desync issue, but even outside of that, the notes didn't feel like an extension of the song the way they are in other rhythm games.
That being said, the music is great, and the theming is fantastic (I love the dog paw mouse cursor). I'd love to see it extended into a stylish "results" screen at the end of each song.
Overall great job though, thoroughly enjoyed it!