// This code creates a square that changes color when the user
// mouses over it, then goes back to white when the user moves
// away.

void setup() {
  size(400,100);
  rectMode(CENTER);
  fill(255);
}

void draw() {
  background(0);
  
  rect(width / 4, height / 2, 40, 40);
  // These are for the extra activity.
  // rect(width / 2, height / 2, 40, 40);
  // rect(3 * width / 4, height / 2, 40, 40);
}