This is a pretty cool game. But why is the tutorial at the end of a level, not at the beginning? When a player finished a level, they already understand the game mechanic.
Also the clear gems reflecting the beam seems to take different paths depending on where it can go to. This makes it a bit unintuitive imho. It would be better if this mechanic was a bit simpler, i.e. the beam always bends at 45degrees for a clear gem, always straight forward for a red gem.