固定背景图片
body{
background-color: rgba(0, 0, 0, 0);
background-position-x: 0%;
background-position-y: 0%;
background-repeat: repeat;
background-attachment: fixed;
background-image: linear-gradient(45deg, rgb(233, 30, 99), rgb(156, 39, 176));
background-size: auto;
background-origin: padding-box;
background-clip: border-box;
}