/* ===== 全局基调（与首页完全统一） ===== */
        :root {
            --primary: #2563eb;
            --primary-dark: #1d4ed8;
            --accent-cyan: #0ea5e9;
            --gray-50: #f8fafc;
            --gray-100: #f1f5f9;
            --gray-200: #e2e8f0;
            --gray-600: #475569;
            --gray-800: #1e293b;
            --white: #ffffff;
            --shadow-sm: 0 4px 12px rgba(0,0,0,0.04);
            --shadow-md: 0 12px 28px rgba(0,0,0,0.06);
            --shadow-lg: 0 20px 40px -8px rgba(0,0,0,0.1);
            --radius-lg: 1.5rem;
            --radius-xl: 2rem;
            --transition: all 0.25s ease;
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        body {
            font-family: 'Inter', system-ui, -apple-system, 'Segoe UI', Roboto, sans-serif;
            background: #f8fafc;
            color: #0f172a;
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
        }
        .container {
            max-width: 1280px;
            margin: 0 auto;
            padding: 0 24px;
        }

        /* ===== 导航栏（与首页一致） ===== */
        .navbar {
            background: rgba(255,255,255,0.92);
            backdrop-filter: blur(12px);
            box-shadow: 0 4px 20px rgba(0,0,0,0.04);
            position: sticky;
            top: 0;
            z-index: 100;
            border-bottom: 1px solid rgba(226,232,240,0.8);
        }
        .nav-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            padding: 0.8rem 0;
        }
        .logo-link {
            display: flex;
            align-items: center;
            gap: 10px;
            text-decoration: none;
        }
        .logo-mark {
            background: linear-gradient(135deg, var(--primary), var(--accent-cyan));
            width: 40px;
            height: 40px;
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: white;
            font-weight: 700;
            font-size: 22px;
            box-shadow: 0 4px 12px rgba(37,99,235,0.3);
        }
        .logo-word {
            font-size: 1.6rem;
            font-weight: 700;
            background: linear-gradient(120deg, #1e3a8a, #2563eb);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
        }
        .nav-menu {
            display: flex;
            gap: 24px;
            align-items: center;
            flex-wrap: wrap;
        }
        .nav-item {
            text-decoration: none;
            font-weight: 500;
            color: var(--gray-800);
            transition: var(--transition);
            font-size: 0.95rem;
            position: relative;
            padding: 0.25rem 0;
        }
        .nav-item:hover,
        .nav-item.current {
            color: var(--primary);
            transform: translateY(-1px);
        }
        .nav-item.current::after {
            content: '';
            position: absolute;
            bottom: -6px;
            left: 0;
            right: 0;
            height: 2px;
            background: var(--primary);
            border-radius: 2px;
        }

        /* ===== 页面头部 ===== */
        .page-header {
            background: linear-gradient(135deg, #eef2ff 0%, #ffffff 60%, #f0f9ff 100%);
            padding: 3rem 0;
            text-align: center;
            border-bottom: 1px solid #e9eef3;
        }
        .page-header h1 {
            font-size: 2.5rem;
            font-weight: 800;
            background: linear-gradient(to right, #0c4a6e, var(--primary), var(--accent-cyan));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            margin-bottom: 0.8rem;
        }
        .page-header p {
            color: var(--gray-600);
            font-size: 1.1rem;
            max-width: 700px;
            margin: 0 auto;
        }

        /* ===== 通用区块 ===== */
        .section-block {
            margin: 4rem 0;
        }
        .section-title {
            font-size: 2rem;
            font-weight: 700;
            text-align: center;
            background: linear-gradient(135deg, var(--primary-dark), var(--accent-cyan));
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
            background-clip: text;
            margin-bottom: 0.8rem;
            position: relative;
        }
        .section-title::after {
            content: '';
            display: block;
            width: 60px;
            height: 4px;
            background: linear-gradient(90deg, var(--primary), var(--accent-cyan));
            border-radius: 4px;
            margin: 0.8rem auto 1.5rem;
        }
        .section-sub {
            text-align: center;
            color: var(--gray-600);
            margin-bottom: 2.5rem;
            max-width: 680px;
            margin-left: auto;
            margin-right: auto;
        }

        /* ===== 卡片通用 ===== */
        .card {
            background: white;
            border-radius: var(--radius-lg);
            padding: 1.8rem;
            box-shadow: var(--shadow-sm);
            transition: var(--transition);
            border: 1px solid var(--gray-100);
        }
        .card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-md);
        }

        /* ===== 界面概览卡片 ===== */
        .interface-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 1.5rem;
            margin-top: 2rem;
        }
        .interface-card {
            text-align: center;
        }
        .interface-card i {
            font-size: 2.5rem;
            color: var(--primary);
            margin-bottom: 1rem;
        }
        .interface-card h4 {
            font-size: 1.2rem;
            margin-bottom: 0.5rem;
        }
        .interface-card p {
            color: var(--gray-600);
            font-size: 0.9rem;
        }

        /* ===== 步骤卡片（添加节点三方式） ===== */
        .steps-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 1.8rem;
            margin-top: 2rem;
        }
        .step-card {
            background: white;
            border-radius: var(--radius-xl);
            padding: 2rem;
            box-shadow: var(--shadow-sm);
            border-top: 4px solid var(--primary);
            transition: var(--transition);
            display: flex;
            flex-direction: column;
        }
        .step-card:hover {
            transform: translateY(-5px);
            box-shadow: var(--shadow-lg);
        }
        .step-num {
            font-size: 2.5rem;
            font-weight: 800;
            color: rgba(37,99,235,0.2);
            line-height: 1;
            margin-bottom: 0.5rem;
        }
        .step-card h3 {
            font-size: 1.4rem;
            margin-bottom: 1rem;
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }
        .step-card p {
            color: var(--gray-600);
            flex: 1;
            font-size: 0.95rem;
            line-height: 1.7;
        }
        .step-tip {
            margin-top: 1.2rem;
            font-size: 0.8rem;
            color: var(--primary);
            font-weight: 500;
        }

        /* ===== 模式切换图示 ===== */
        .mode-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 1.5rem;
            margin-top: 2rem;
        }
        .mode-card {
            text-align: center;
            background: white;
            border-radius: var(--radius-lg);
            padding: 1.8rem;
            box-shadow: var(--shadow-sm);
            border: 1px solid var(--gray-100);
            transition: var(--transition);
        }
        .mode-card:hover {
            border-color: var(--primary);
            box-shadow: var(--shadow-md);
        }
        .mode-icon {
            font-size: 2.8rem;
            color: var(--primary);
            margin-bottom: 1rem;
        }
        .mode-card h4 {
            font-size: 1.2rem;
            margin-bottom: 0.8rem;
        }
        .mode-card p {
            color: var(--gray-600);
            font-size: 0.9rem;
        }

        /* ===== FAQ 网格 ===== */
        .faq-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 1.5rem;
            margin-top: 2rem;
        }
        .faq-item {
            background: white;
            border-radius: 1rem;
            padding: 1.5rem;
            border-left: 4px solid var(--primary);
            box-shadow: var(--shadow-sm);
        }
        .faq-item strong {
            display: block;
            margin-bottom: 0.5rem;
            color: var(--gray-800);
        }
        .faq-item p {
            color: var(--gray-600);
            font-size: 0.9rem;
        }

        /* ===== 对比表格（订阅方式） ===== */
        .compare-wrapper {
            overflow-x: auto;
            border-radius: 1.5rem;
            box-shadow: var(--shadow-md);
            background: white;
            margin-top: 2rem;
        }
        table {
            width: 100%;
            border-collapse: collapse;
            min-width: 650px;
        }
        th {
            background: var(--gray-100);
            padding: 1rem;
            font-weight: 600;
            text-align: left;
            border-bottom: 2px solid var(--gray-200);
        }
        td {
            padding: 1rem;
            border-bottom: 1px solid var(--gray-100);
            color: #334155;
        }
        .tag {
            font-size: 0.8rem;
            padding: 4px 12px;
            border-radius: 20px;
            font-weight: 600;
            white-space: nowrap;
        }
        .tag-blue { background: #dbeafe; color: #1e40af; }
        .tag-orange { background: #ffedd5; color: #c2410c; }
        .tag-purple { background: #ede9fe; color: #6d28d9; }
        .tag-green { background: #d1fae5; color: #065f46; }

        /* ===== 底部CTA ===== */
        .cta-banner {
            background: linear-gradient(105deg, #eef2ff 0%, #ffffff 80%);
            border-radius: var(--radius-xl);
            padding: 3rem 2.5rem;
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            justify-content: space-between;
            gap: 2rem;
            border: 1px solid #e0e7ff;
            box-shadow: var(--shadow-md);
            margin: 3rem 0;
        }
        .btn-primary {
            background: var(--primary);
            color: white;
            padding: 14px 32px;
            border-radius: 40px;
            font-weight: 600;
            text-decoration: none;
            display: inline-flex;
            align-items: center;
            gap: 8px;
            transition: var(--transition);
            box-shadow: 0 4px 12px rgba(37,99,235,0.25);
            white-space: nowrap;
        }
        .btn-primary:hover {
            background: var(--primary-dark);
            transform: translateY(-3px);
            box-shadow: 0 16px 28px -8px rgba(37,99,235,0.4);
        }
        .btn-outline {
            background: white;
            border: 1px solid var(--gray-200);
            padding: 12px 28px;
            border-radius: 40px;
            font-weight: 600;
            text-decoration: none;
            color: var(--gray-800);
            display: inline-flex;
            align-items: center;
            gap: 8px;
            transition: var(--transition);
        }
        .btn-outline:hover {
            border-color: var(--primary);
            color: var(--primary);
        }

        /* ===== 页脚（与首页统一） ===== */
        .footer {
            background: #0f172a;
            color: #cbd5e1;
            padding: 4rem 0 2rem;
            margin-top: 4rem;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 1.5fr 1fr 1fr 1fr;
            gap: 2rem;
            margin-bottom: 2rem;
        }
        .footer-logo-text {
            font-size: 1.5rem;
            font-weight: 700;
            color: white;
            margin-bottom: 0.8rem;
        }
        .footer-col h4 {
            color: white;
            margin-bottom: 0.8rem;
        }
        .footer-col ul {
            list-style: none;
        }
        .footer-col li {
            margin-bottom: 6px;
        }
        .footer-col a {
            color: #94a3b8;
            text-decoration: none;
            transition: color 0.2s;
        }
        .footer-col a:hover {
            color: white;
        }
        .footer-bar {
            border-top: 1px solid #1e293b;
            padding-top: 2rem;
            text-align: center;
            font-size: 0.85rem;
            color: #64748b;
        }

        /* 响应式 */
        @media (max-width: 1024px) {
            .interface-grid,
            .steps-grid,
            .mode-grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        @media (max-width: 768px) {
            .nav-inner {
                flex-direction: column;
                gap: 12px;
            }
            .nav-menu {
                justify-content: center;
            }
            .interface-grid,
            .steps-grid,
            .mode-grid,
            .faq-grid,
            .footer-grid {
                grid-template-columns: 1fr;
            }
            .page-header h1 {
                font-size: 2rem;
            }
        }