Feature: Consider limiting demo emojisplosions to the explosion container?

[JoshuaKGoldberg]

Right now, emojis pop out of the explosion container and over the surrounding page:

It'd be nice to limit them to the container for demo purposes.

One drawback, though, is that this might overcomplicate the code for the demos? They're really nice and straightforward now. It would be unfortunate to make them much more verbose for this...