Ask Marilyn column on the Problem published in Parade Magazine in 1990
MDN Web Docs entry on the Document Object Model
MDN Web Docs entry on the basics of CSS
p5.js tutorial on basic CSS and the p5 style() function
p5.js tutorial on using the selectAll() function to add events to multiple DOM elements
Livestream with Monty Hall challenge.
by Mathieu Blanchette
by Jason Heglund