I hadn't played chess in a long while, that was fun.
Some random thoughts:
- I like your choice of music for this game, it goes very well with it.
- The chess assets look good!
- Did you do the AI by hand? it's not a particularly strong chess AI, compared to professional chess games, but if you have done it by hand it's actually quite impressive!
- Perhaps some kind of animation only for the AI pieces could be helpful to track their movement. I wouldn't use it for the player pieces though, instant movement feels better for those (for me at least).
Very good job, even more so considering your time constraints!