text: class Stone{
      constructor(x, y, width, height) {
          var options = {
            restitution:0.8
          };
      
          this.body = Bodies.rectangle(x, y, width, height, options);
          this.width = width;
          this.height = height;
          this.color = this.color;
          World.add(world, this.body);
        }
      
        show() {
          var pos = this.body.position;
          push();
          translate(pos.x, pos.y);
          strokeWeight(1);
          fill("white");
          ellipse(CENTER);
          ellipse(0,0,this.width,this.height);
          noStroke();
          
          pop();
        }
      }
  