Great idea combining two styles, really don't see it coming when I saw the theme. The music fits the the gameplay and the graphics are simple but good as it needs to be.
I feel like the game could benefit a lot if the shoot went for the mouse direction (at least make sense when I was shooting with it), or at least the player face the side the mouse is.
I faced a problem when jumping and colliding with the platformer, felt like stuck there.
But, overall, a interesting idea into a good game. Congrats!