I love that you have a README and License file (main criteria for open source category). I'd love to see more in your README too. Add what's on your submission page: https://valentino-collazo.itch.io/elemental-delivery since that's super in depth and I love all the emojis and screenshots.
Loving the menu page; beautiful animations, chill, easy to read the title. Music is great too, and fits the vibe you're going for. The art-style is awesome and I'm really loving the juxtaposition between the blurred background and the 8-bit graphics in the foreground, really digging this!
The inclusion of a tutorial is great, and I love that you changed "keyboard" to "runeboard", very on theme. Great take on the balance theme. Very interesting and creative controls. I liked the tutorial at the start, maybe have the first level without any platforms or barriers so the player can get used to the controls and the physics in the game without obstacles in the way. Also maybe make it so it's just delivering one of each on the first level; give players that quicker gratification to keep them in the game.
Great job on your submission and I enjoyed the physics in this too.