Really well done for your first game jam! I'm impressed with how many different effects you managed to cram in and I want to keep playing just to see more! Some people have already mentioned but it seems there is a mismatch between the expected screen size and the window size assigned in itch! Make sure to line up the resolution you set in the project settings in godot with the play window size you set in the itch settings for your project, then there should be a fullscreen button included as well!