Pretty interesting concept! I also loved whatever you did to those imaginary platforms and the fact that the character is literally an i (didn't notice until halfway through lol).
One thing that would make this game better is having more clarity on how your mechanic works and what things are. I thought at first that the yellow things were just coins so I was picking them up left and right and then proceeding to get stuck and confused.
Although its really cool that -i and -1 reverse gravity, I think it should be explained better rather than just writing out "i^2 = -1". And just in general, I think you should try and explain your mechanic in a way that doesn't assume the player knows what i is.
A piece of advise that was once told to me is "while developing games, assume all your players are absolute idiots" and I shall pass that onto you. Really enjoyed playing your game though, cheers!