Mein Abschlussprojekt für den Kurs: Creative Coding: Programmiere visuelles Material mit JavaScript

Mein Abschlussprojekt für den Kurs: Creative Coding: Programmiere visuelles Material mit JavaScript

The original idea was that the bubbles would emerge from the yellow circle.
I could not find a way to keep them inside the circle/let them bounce as soon as they pass the circle outline. Another possibility would be that the bubbles change color, to get red bubbles on yellow background, yellow bubbles on red background....