.lunbo{

  height: 640px;

  width: 100%;

  background-position: -280px;

  margin-top: 103px;

  -webkit-animation: lunbo 5s infinite alternate;

}

@-webkit-keyframes lunbo{

  0%{

    background-image:url("../img/jinli_images/04_1515047442501.jpg");

  }

  100%{

    background-image:url("../img/jinli_images/02_1517536570441.jpg");

  }

}