let rectY = 100;

let rectWidth = 200;

let rectHeight = 200;

let rightEdge = rectX + rectWidth;

​

function setup() {

  createCanvas(windowWidth, windowHeight);

}

​

function draw() {

  background(220, 10, 120);

​

  if (mouseX > rectX && mouseX < rightEdge) {

    fill(255, 190, 0);

  } else {

    fill(255);

  }

​

  rect(rectX, rectY, rectWidth, rectHeight);

}

​