​

function setup() {

  createCanvas(400, 400);

}

​

function draw() {

  background(220);

  let circleNum=10;

  let x= width/2;

  let y=height/2;

  let baseSize=200;

  for(let i=0; i<circleNum; i++){

    let size = baseSize - i*(baseSize/circleNum);

    circle(x,y,size)

  }

}