Adorable and great game! 'Up and down' and 'wrap your head around this' were my favourite levels.
I also loved the aesthetics of the game, and minor details such as how there is a slight difference between sound effects whenever you scale up or down. Also Music was great for this!
One little feedback is that the background for the cave levels makes the gems a little harder to see if you don't know where they are, but nonetheless very polished. Great game!