* {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        body {
            background: #f5f7fa;
            font-family: "微软雅黑", Microsoft Yahei, sans-serif;
            color: #555;
            line-height: 2;
            /* 给主体顶部留出固定导航高度，避免内容被遮挡 */
            padding-top: 60px;
        }
        /* 头部导航 固定定位 */
        .header {
            width: 100%;
            height: 60px;
            background: #ffffff;
            box-shadow: 0 1px 6px #eee;
            position: fixed;
            top: 0;
            left: 0;
            z-index: 999;
        }
        .header-inner {
            width: 1300px;
            margin: 0 auto;
            height: 100%;
            display: flex;
            align-items: center;
            justify-content: space-between;
        }
        .logo {
            font-size: 21px;
            font-weight: bold;
            color: #15ac70;
            text-decoration: none;
            width: 207px;height: 40px;
        }.logo img{
            width: 207px;height: 40px;
        }
        .nav a {
            text-decoration: none;
            color: #333;
            margin: 0 10px;
            font-size: 16px;
            font-weight: 500;
        }
        .nav a:hover {
            color: #15ac70;
        }
        /* 主内容容器 */
        .wrap {
            width: 1300px;
            margin: 40px auto;
            background: #fff;
            padding: 50px;
            border-radius: 10px;
            box-shadow: 0 2px 10px #eee;
        }.wrap img{
            margin: 20px;
            border-radius: 20px;
        }
        .title-top {
            text-align: center;
            border-bottom: 1px solid #eee;
            padding-bottom: 20px;
            margin-bottom: 40px;
        }
        .title-top h1 {
            font-size: 28px;
            color: #222;
            margin-bottom: 8px;
        }
        .title-top p {
            color: #999;
        }
        h2 {
            font-size: 18px;
            border-left: 4px solid #15ac70;
            padding-left: 12px;
            color: #15ac70;
            margin: 30px 0 15px;
        }
        h3 {
            font-size: 16px;
            margin: 15px 0 8px;
            color: #333;
        }
        p {
            text-indent: 2em;
            font-size: 15px;
            margin-bottom: 12px;
        }
        /* 底部 */
        .footer {
            text-align: center;
            font-size: 14px;
            color: #999;
            padding: 30px 0;
            border-top: 1px solid #eee;
            background: #fff;
        }
        /* 手机自适应 */
        @media (max-width: 1300px) {
            .header-inner, .wrap {
                width: 96%;
            }
        }
        @media (max-width: 768px) {
            .header {
                height: auto;
            }
            .header-inner {
                padding: 10px 0;
                flex-direction: column;
            }
            .nav {
                margin-top: 8px;
            }
            body {
                padding-top: 80px;
            }
            .wrap {
                padding: 20px;
            }
        }