.teach-video-box{position:fixed;width:1200px;height:675px;top:50%;left:50%;transform:translate(-50%,-50%);background-color:#fff;z-index:999;.header-close{position:absolute;top:20px;right:20px;cursor:pointer;z-index:1000;img{width:20px;height:20px}}video{width:100%;height:100%}}.download-app{position:fixed;top:50px;right:0;display:flex;align-items:center;justify-content:center;flex-direction:column;img{width:240px;height:240px}p{color:#d34242;font-size:18px;font-weight:900}}