createCanvas(400, 400);

}

​

 let blueHue= 0 

 let speedX = 0.5

function draw() {

  background(34, 15, blueHue);

  if ((blueHue > 100) || (blueHue<0 )){

    speedX *= -1

​

  }

  blueHue= blueHue + speedX

}