JavaScript实现抛物线加入购物车动画效果

.flyer {
      display: block;
      width: 50px;
      height: 50px;
      border-radius: 50px;
      position: fixed;
      margin-left: 50px;
      z-index: 9999;
    }
    .cart img{
      width: 60px;
      height: 60px;
      padding: 5px 0 0 250px;
    }
    .cartBox span{
      display: block;
      color: white;
      position: absolute;
      left: 282px;
      top: 226px;
      width: 25px;
      height: 25px;
      border-radius: 50%;
      text-align: center;
      line-height: 25px;
      background-color: red;
    }

<div class="box"> 
    ![](img/1.jpg)
  </div>
  <div class="cartBox">
    <div class="cart">
      <i id="end"></i>
        ![](img/2.jpg)
        <span>0</span>
    </div>
  </div>

<script src="js/jquery-3.0.0.min.js"></script>
<script src="js/jquery.fly.min.js"></script>

$('.box').on('click', addCart);
    var num = 0;
    function addCart(event) {
      var offset = $('#end').offset(), flyer = $('![](img/1.jpg)');
      flyer.fly({
        start: {
          left: event.pageX,
          top: event.pageY
        },
        end: {
          left: offset.left + 280,
          top: offset.top,
          width: 0,
          height: 0
        }
      });
      num++;  
      $('.cartBox span').text(num);
    }