body{
        background: url(https://gimg2.baidu.com/image_search/src=http%3A%2F%2Fpic1.win4000.com%2Fwallpaper%2F2017-11-27%2F5a1b7447a5b98.jpg%3Fdown&refer=http%3A%2F%2Fpic1.win4000.com&app=2002&size=f9999,10000&q=a80&n=0&g=0n&fmt=auto?sec=1656559127&t=1df23cf36794fac632c9a50a0f57aced) no-repeat;
    background-size: cover;
    background-attachment: fixed;
}
#leftcontentcontainer{
    margin-top:0
}