body:after{position:fixed;content:"";left:-1000px;top:-1000px;animation:shadow-preload .1s;animation-delay:3s}@keyframes shadow-preload{0%{background-image:url(https://cdn.dcloud.net.cn/img/shadow-grey.png)}to{background-image:url(https://cdn.dcloud.net.cn/img/shadow-grey.png)}}