//createCanvas(800, 400);

//}

​

//function draw() {

  //background(220);

    //top

  //line (200,100,600,100)

    //bottom

  //line(200,300,600,300)

    //left

  //line(200,100,200,300)

    //right

  //line(600,100,600,300)

//}

​

let a, b, c, d;

let speed = 1;

​

function setup() {

  createCanvas(500, 400);

​

  a = 0.25 * width;

  b = 0.25 * height;

  c = 0.75 * width;

  d = 0.75 * height;

}

​

function draw() {

  background(220);

  // Center of Rectangle

  let centerX = width / 2;

  let centerY = height / 2;

  if (centerX < mouseX) {

    a += speed;

    c += speed;

  }

  if (centerX > mouseX) {

    a -= speed;

    c -= speed;

  }

  if (centerY < mouseY) {

    b += speed;

    d += speed;

  }

  if (centerY > mouseY) {

    b -= speed;

    d -= speed;

  }

​

  line(a, b, c, b); 

  line(a, d, c, d); 

  line(a, b, a, d); 

  line(c, b, c, d); 

}