The game fits the theme well. I liked the fire effect when looking at objects that can be scaled, it's very performant. At first I found the lack of vertical movement in the camera frustrating but over the course of the levels came to realize this was an intentional limitation to make some later levels more difficult.
Two suggestions: There are some free asset packs you can get on the Unity Asset Store (or other asset stores) that area allowed for this type of game, and if you only intend to use the simple shapes anyways, that can be a quick way to introduce some extra visual stimulation to the game.
The other suggestion is adding a kill plane below the level in case the player escapes. It only happened once, but I had to refresh the page to restart the game.
Overall, I enjoyed this.