main > ul{
    display: flex;/*弹性盒模型*/
    width: 1480px;
    height: 910px;
    margin: 50px auto 0;
    /* background-color: blue; */
}
main > ul > li:first-of-type{
    position: relative;/*相对定位*/
    top: 180px;
    left: 180px;
    width: 1300px;
    height: 730px;
    background-color: rgb(248, 248, 248);
}
main > ul > li:first-of-type > section:first-of-type{
    position: absolute;/* 绝对定位 */
    top: -60px;
    left: -60px;
    width: 800px;
    height: 730px;
    background-color: burlywood;
    box-shadow:40px 40px 40px 0px rgba(187, 187, 187,0.9);/*阴影*/
}
main > ul > li:first-of-type > section:nth-child(2){
    position: absolute;/* 绝对定位 */
    top: -110px;
    left: -110px;
    width: 800px;
    height: 730px;
    background-color: chartreuse;
    box-shadow:30px 30px 30px 0px rgba(187, 187, 187,0.9);/*阴影*/
}
main > ul > li:first-of-type > section:last-of-type{
    position: absolute;/* 绝对定位 */
    top: -160px;
    left: -160px;
    width: 800px;
    height: 730px;
    background-color: crimson;
    box-shadow:20px 20px 20px 0px rgba(187, 187, 187,0.9);/*阴影*/
}
main > ul > li > p{
    position: absolute;/* 绝对定位 */
    /* top: 355px; */
    left: 900px;
    width: 500px;
    height: 730px;
    /* background-color: rgb(97, 60, 60); */
}