/* 设置页面背景图片 */
body{background-image: url("../img/2.jpeg");background-repeat: no-repeat;background-position: center center;background-size: cover;background-attachment: fixed;}


#box{text-align: center;}


#box2,#box3{
    width: 540px;
    height: 470px;
}


#btn2{
    margin-right: 550px;
}