/* ================= Reset & Base ================= */
    * {
        margin: 0;
        padding: 0;
        box-sizing: border-box; /* 关键：让padding不撑大盒子 */
    }

    body {
        font-family: "Microsoft YaHei", "PingFang SC", sans-serif;
        background-color: #f9f9f9;
        color: #333;
        line-height: 1.6;
    }

    a { text-decoration: none; color: inherit; transition: 0.3s; }
    ul { list-style: none; }

    /* 通用容器：限制最大宽度并居中 */
    .container {
        max-width: 1200px;
        margin: 0 auto;
        padding: 0 20px; /* 防止在小屏幕上贴边 */
    }

    /* ================= Header (核心修复部分) ================= */
    .header {
        background: #fff;
        box-shadow: 0 2px 15px rgba(0,0,0,0.05); /* 更柔和的阴影 */
        position: sticky;
        top: 0;
        z-index: 1000;
        height: 70px; /* 【关键】给头部一个固定高度 */
        display: flex;
        align-items: center; /* 垂直居中 */
    }

    .header-content {
        width: 100%;
        display: flex;
        justify-content: space-between; /* 左右两端对齐 */
        align-items: center; /* 确保Logo和导航在同一水平线 */
    }

    /* Logo 区域修复 */
    .logo-box {
        display: flex;
        align-items: center;
        gap: 12px; /* Logo图片和文字的间距 */
        height: 100%; /* 继承父级高度 */
    }

    .logo-box img {
        height: 45px; /* 限制高度 */
        width: auto;  /* 宽度自动 */
        display: block;
        object-fit: contain; /* 保证图片不变形 */
    }

    .logo-text {
        font-size: 20px;
        font-weight: bold;
        color: #333;
        white-space: nowrap; /* 强制文字不换行 */
    }

    /* 导航区域修复 */
    .nav {
        display: flex;
        gap: 30px;
        height: 100%;
    }

    .nav a {
        display: flex;
        align-items: center; /* 让链接文字在导航栏高度内垂直居中 */
        height: 100%;
        font-size: 16px;
        color: #555;
        font-weight: 500;
    }

    .nav a:hover {
        color: #2c6eed;
    }

    /* ================= Banner ================= */
    .banner {
        background: linear-gradient(135deg, #2c6eed 0%, #4392ff 100%);
        color: #fff;
        padding: 100px 0;
        text-align: center;
    }

    .banner h1 {
        font-size: 42px;
        margin-bottom: 20px;
        letter-spacing: 2px;
    }

    .banner p {
        font-size: 18px;
        opacity: 0.9;
        max-width: 800px;
        margin: 0 auto 30px;
        line-height: 1.8;
    }

    .btn-primary {
        display: inline-block;
        padding: 12px 35px;
        background: #fff;
        color: #2c6eed;
        border-radius: 50px; /* 圆角按钮更好看 */
        font-weight: bold;
        font-size: 16px;
        box-shadow: 0 4px 10px rgba(0,0,0,0.1);
    }

    .btn-primary:hover {
        transform: translateY(-2px);
        box-shadow: 0 6px 15px rgba(0,0,0,0.2);
    }

    /* ================= Features Section ================= */
    .section {
        padding: 80px 0;
        background: #fff;
    }

    .section-title {
        text-align: center;
        font-size: 32px;
        color: #222;
        margin-bottom: 50px;
        position: relative;
    }

    /* 标题下划线装饰 */
    .section-title::after {
        content: "";
        display: block;
        width: 60px;
        height: 4px;
        background: #2c6eed;
        margin: 15px auto 0;
        border-radius: 2px;
    }

    .grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); /* 响应式网格 */
        gap: 30px;
    }

    .card {
        background: #f8faff;
        padding: 40px 25px;
        border-radius: 12px;
        text-align: center;
        transition: 0.3s;
        border: 1px solid #eee;
    }

    .card:hover {
        transform: translateY(-5px);
        box-shadow: 0 10px 20px rgba(44, 110, 237, 0.1);
        border-color: #2c6eed;
    }

    .card h3 {
        font-size: 20px;
        margin-bottom: 15px;
        color: #2c6eed;
    }

    .card p {
        color: #666;
        font-size: 14px;
    }

    /* ================= Footer ================= */
    .footer {
        background: #222;
        color: #999;
        padding: 50px 0 30px;
        text-align: center;
        font-size: 14px;
    }

    .footer p { margin-bottom: 10px; }
    .footer a { color: #999; margin: 0 5px; }
    .footer a:hover { color: #fff; }