Just start the project and wait the background react to sound levels. If prompted, please, authorize the browser to use microphone or webcam (and enable or unmute it from the computer mixer panel) to see the the animation. The little critter below are sleeping and doing enough noise should wake them, but just for the time of a yawn, in this season (all seasons, all years) they usually are hibernating.
The main challenge of this project was to animate the sound critters without lagging the background and without making the cpu of my laptop overeat too much. Strangely, at least for me, a message passing solution was not the most efficient one, at least hearing my laptop cpu fan. I had to resort to a forever cicle in every critter clone to have acceptaple performances. The critter are the result of a mistake, as I overlooked the request to change the background of the project when the ambient noise rises. They were too cute, to me, and do not had hearth to remove them from the project.