I'll be honest... Although your game seems promising at first, this is not very fun. The jumps feel pretty bad, but this can be an intended feature, depending of the game. Though, the level 3 is a brutal difficulty spike and you're forced to go back square one if you fail, which will almost always happen frame 1 (even IWBTG don't do it that quickly) the first time you pass level 2 and can happen in level 4 (the start of the level isn't great game design) with a gravity a bit more polished and a real vertical acceleration the game could be good. I also think you should not have to explain why your game fits in the theme of the jam or, at least, only if someone asks. The gravity control also feels pretty bad, why didn't you just make "when you press up, you change gravity" instead of "your gravity flips depending of if you press up or down arrow". TLDR, this game could've been great but have a lot of flaws, tho it means there is a lot of room for improvement and, at least, you already made a whole game even if it's very short.