I really liked the graphics; the color palette you chose is perfect.
At first, I had a little trouble spotting the chests, as I didn't realize you could interact with them. I would suggest adding some kind of visual effect or animation to highlight them, although given the limited time you had, it's understandable that you couldn't include that.
It's a game with a lot of content; I'm sure you put a lot of work into it.
Great job, congratulations!