let colours;

​

function setup() {

  createCanvas(400, 400);

  target = new Target();

  colours = {

    white: color(255),

    black: color(0),

  }

}

​

function draw() {

  background(0);

  if (mouseIsPressed) {

    let distance = dist(mouseX, mouseY, target.x, target.y);

    let amount = map(distance, 0, 100, 0, 1);

    let colour = lerpColor(colours.white, colours.black, amount);

    background(colour);

    if (distance < 5) {

      background(0, 255, 0);

    }

  }

}