效果图

教程开始

将下面代码放入自定义css中

body:after {
    content: " ";
    position: fixed;
    inset: 0;
    background-color: white;
    z-index: 999;
    background-image: url(图片链接);
    background-repeat: no-repeat;
    background-position: center;
    background-size: 30%;
    animation: fadeOut 3s;
    animation-fill-mode: forwards;
    -webkit-transition: fadeOut 3s;
    transition: fadeOut 3s;
    pointer-events: none;
}
@keyframes fadeOut {
  50% {
    opacity: 1;
  }
 
  100% {
    opacity: 0;
  }
}