#maomao {
            position: fixed;
            bottom: 40px;
            right: -5px;
            width: 57px;
            height: 70px;
            background-image: url(https://cdn.jsdelivr.net/gh/muzihuaner/huancdn/img/20210808215127.svg);
            background-position: center;
            background-size: cover;
            background-repeat: no-repeat;
            transition: background .3s;
        }
#maomao:hover {
            background-position: 60px 50%;
        }

/* 头部 */
#header {
    position: relative;
    height: 280px;
    margin: 0;
    background: #020031;
    background: -moz-linear-gradient(45deg,#020031 0,#6d3353 100%);
    background: -webkit-gradient(linear,left bottom,right top,color-stop(0%,#020031),color-stop(100%,#6d3353));
    background: -webkit-linear-gradient(45deg,#020031 0,#6d3353 100%);
    background: -o-linear-gradient(45deg,#020031 0,#6d3353 100%);
    background: -ms-linear-gradient(45deg,#020031 0,#6d3353 100%);
    background: linear-gradient(45deg,#020031 0,#6d3353 100%);
    filter: progid:DXImageTransform.Microsoft.gradient(startColorstr='#020031', endColorstr='#6d3353', GradientType=1);
    -webkit-box-shadow: inset 0 3px 7px rgba(0,0,0,.2),inset 0 -3px 7px rgba(0,0,0,.2);
    -moz-box-shadow: inset 0 3px 7px rgba(0,0,0,.2),inset 0 -3px 7px rgba(0,0,0,.2);
    box-shadow: inset 0 3px 7px rgba(0,0,0,.2),inset 0 -3px 7px rgba(0,0,0,.2);
}