Sweet you found the bug easter egg at the end! That wont happen every time, but when it happened while I was testing, I HAD to leave it in. It was too funny. It's actually trivially easy to fix, but my heart wouldn't let me do it. :P
That growing animation is a texture in a Line2D with its points animated with keyframes in an AnimationPlayer, in case you're curious.
I intentionally built this version to use the page as its load/unload this time around. You can always hit escape to jump back to the starting screen at any time. Cheers.