body {
background: url(https://i.loli.net/2020/09/13/pDa4jmrsIkGWh36.jpg) fixed;
background-size: cover;
background-repeat: no-repeat;
opacity: 80%;
}

/*去除文章评论下的广告*/
div[id^="ad_"] {
    display: none;
}
div[class^="c_ad"] {
    display: none;
}
div[id^="under_post"] {
    display: none;
}

#back-to-top123 {
    background-color: #00CD00;
    bottom: 0;
    box-shadow: 0 0 6px #00CD00;
    color: #444444;
    padding: 10px 10px;
    position: fixed;
    right: 50px;
    cursor: pointer;
}