We mostly made this game to see if we could :)
We wanted to do it absolutely from scratch and using the least amount of stuff possible, and neither of us had used a lot of JavaScript before.

The little piece of code that determines if an arrangement is solvable was written adapting what we found here:
https://datawookie.dev/blog/2019/04/sliding-puzzle-solvable/
and of course we googled a lot.

We'll figure out how to improve it, maybe.
But now the holidays are over and we're back to work.
Happy new year!