I’m very impressed that you managed to create something that is actually a functioning game with a pile of DOM nodes managed by Svelte. While I knew such a thing was entirely possible, a more traditional method of creating a web based game would be to use HTML5 Canvas exclusively managed by Javascript (not that you need to do anything differently).
The other advantage of your approach is that your game is probably the only one that has felt truly web-native, in the sense that I did not need to wait 30 seconds for some bloated WASM thing to bring along its garbage collector like everyone who used one of the major engines (including myself).
I think it is also impressive that you chose a manageable scope, implemented all of it before the deadline, and the game itself was actually entertaining.
I would echo the constructive criticism that some sort of background art would be helpful. The game currently feels “floaty” without it.