p,span{display:inline-block}body{padding:50px;position:relative;font:14px "Microsoft YaHei",Arial,sans-serif}@media screen and (max-width:800px) {body{padding:50px 8px 0 0}}p{margin-left:10px}a{color:#000;text-decoration:none}#back-to-index{display:block;width:50px;height:35px;padding-top:15px;text-align:center;border-radius:50%;background:#40c4ff;box-shadow:2px 2px 10px #dcdcdc;cursor:default;position:fixed;left:10px;top:10px;z-index:10;transition-duration:.3s}#back-to-index:hover{background:#0094cc;box-shadow:2px 2px 10px gray;color:#fff}