This is a really neat concept! But a few nitpicks:
- The browser version crashes on Mac Safari, apparently it uses too much memory.
- The numbering of the dolls seems reversed to what I'd expect. 1 should be largest.
- It's a little weird that I don't have to get all the dolls to the finish line.
- Sometimes the spacebar causes a doll to pop in when I want a third doll to pop out.
- Aesthetically, it's very brown and the separation between foreground and background isn't as clear as it could be.