I love the art style! It's simple but dynamic, and unique. The black/white contrasting with  the colored words for instructions and things you should pay attention to works really well.

I love the intro and story! That's a great touch to add, and to contain the "tutorial" within that.

You did great with sound effects and feedback, even with the menus in the intro making noises as you click through.

And the music is great haha

That's great how you include the level information (speed/time) embedded in the level itself (rather than a HUD or menu) I like that.

That's really neat how you included upgrades to give the player options, have them make decisions, and play to their style.

And overall, the mechanic of changing gravity as a mechanic is super interesting!

Some thoughts for improvement:

• One thing I thought was a little unclear was what was happening when the player "exploded" haha. The story is, the bad guys caught up and shot him, right? I think somehow having them in the background, or even showing a bullet whizzing up to the bunny would be helpful.
• Also, my first couple of play throughs, I was trying to ake everything in and wasn't paying close attention to the timer, so I was a bit confused why the bunny was exploding - I'm thinking having the timer pulse and some count down noise effects when its the final 3 seconds would be some helpful juice for that.
• I think the start of the game could be a little slower and slowly introduce concepts, mechanics one at a time. I found myself a bit overwhelmed the first couple of play throughs (not that it took too much effort to figure it all out)
• To be honest, I'm not quite sure why you want Gravity Charges? I thought that you needed them to change gravity, but I felt like I could change gravity whenever I wanted, so accumulating them didn't seem worth it?
• I couldn't get past this one point haha  

Overall, I think this is one of the most entertaining & polished games I've played in a game jam, well done!