Super creative on the theme. I like the parallax and the character designs.
I wish the movement was less floaty, as in I'd prefer higher acceleration on the player movement. Would make me feel more in control as the player, like I'm fighting the level and not the controls. The platforms can move faster to balance out the difficulty.
I wish you could maneuver up and down on the screen as well.
Good job on your first game jam entry! Keep adding features to it.