:root {
            --brand: #1d4ed8;
            --brand-deep: #1e3a8a;
            --brand-hover: #173fad;
            --brand-light: #eff6ff;
            --brand-ghost: #eef2ff;
            --accent: #f59e0b;
            --accent-light: #fffbeb;
            --dark: #0f172a;
            --dark-mid: #1e293b;
            --text: #1e293b;
            --text-sub: #334155;
            --text-muted: #475569;
            --text-light: #64748b;
            --border: #e8ecf1;
            --border-light: #f1f5f9;
            --bg-card: #ffffff;
            --bg-subtle: #f8fafc;
            --bg-footer: #fafcff;
            --white: #ffffff;
            --shadow-xs: 0 1px 3px rgba(0, 0, 0, 0.04);
            --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.05);
            --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.06);
            --shadow-lg: 0 16px 36px rgba(0, 0, 0, 0.08);
            --shadow-xl: 0 24px 48px rgba(0, 0, 0, 0.12);
            --radius-sm: 10px;
            --radius: 20px;
            --radius-lg: 32px;
            --radius-xl: 44px;
            --radius-full: 9999px;
            --transition: 0.22s cubic-bezier(0.4, 0, 0.2, 1);
        }
        * {
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }
        html {
            scroll-behavior: smooth;
            -webkit-text-size-adjust: 100%;
            scroll-padding-top: 90px;
        }
        body {
            font-family: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', 'PingFang SC', 'Microsoft YaHei', 'Noto Sans SC', sans-serif;
            background-color: #fdfcfb;
            color: var(--text);
            line-height: 1.65;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
            letter-spacing: 0.01em;
        }

        /* ===== HEADER 与首页一致 ===== */
        .header {
            position: sticky;
            top: 0;
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(14px);
            -webkit-backdrop-filter: blur(14px);
            border-bottom: 1px solid var(--border);
            z-index: 100;
            box-shadow: var(--shadow-xs);
        }
        .nav-container {
            max-width: 1280px;
            margin: 0 auto;
            padding: 0.85rem 2rem;
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 0.8rem;
        }
        .logo-area {
            display: flex;
            align-items: center;
            gap: 0.5rem;
            text-decoration: none;
            flex-shrink: 0;
        }
        .logo-icon {
            width: 38px;
            height: 38px;
            border-radius: 10px;
            background: linear-gradient(135deg, #1d4ed8 0%, #3b82f6 50%, #60a5fa 100%);
            display: flex;
            align-items: center;
            justify-content: center;
            color: #fff;
            font-weight: 900;
            font-size: 1.1rem;
            letter-spacing: -0.03em;
            box-shadow: 0 3px 10px rgba(29, 78, 216, 0.25);
        }
        .logo-text {
            font-weight: 800;
            font-size: 1.6rem;
            letter-spacing: -0.03em;
            color: var(--dark);
            line-height: 1;
        }
        .logo-text span {
            color: var(--brand);
        }
        .logo-badge {
            background: var(--brand-light);
            padding: 0.18rem 0.6rem;
            border-radius: 40px;
            font-size: 0.65rem;
            font-weight: 700;
            color: var(--brand-deep);
            letter-spacing: 0.02em;
            white-space: nowrap;
        }
        .nav-links {
            display: flex;
            gap: 1.4rem;
            align-items: center;
            flex-wrap: wrap;
            list-style: none;
        }
        .nav-links a {
            text-decoration: none;
            font-weight: 500;
            color: #334155;
            transition: color var(--transition);
            font-size: 0.93rem;
            white-space: nowrap;
            position: relative;
            padding: 0.25rem 0;
        }
        .nav-links a::after {
            content: '';
            position: absolute;
            bottom: -2px;
            left: 0;
            width: 0;
            height: 2px;
            background: var(--brand);
            border-radius: 2px;
            transition: width var(--transition);
        }
        .nav-links a:hover,
        .nav-links a.active {
            color: var(--brand);
        }
        .nav-links a:hover::after,
        .nav-links a.active::after {
            width: 100%;
        }
        .btn-outline-nav {
            border: 1.5px solid #d1d5db;
            background: transparent;
            padding: 0.5rem 1.15rem;
            border-radius: 40px;
            font-weight: 600;
            cursor: pointer;
            transition: all var(--transition);
            font-size: 0.88rem;
            white-space: nowrap;
            text-decoration: none;
            color: #1e293b;
        }
        .btn-outline-nav:hover {
            background-color: #f9fafb;
            border-color: #9ca3af;
        }
        .btn-primary-sm {
            background: var(--brand);
            color: #fff;
            border: none;
            padding: 0.5rem 1.25rem;
            border-radius: 40px;
            font-weight: 600;
            cursor: pointer;
            transition: all var(--transition);
            text-decoration: none;
            font-size: 0.88rem;
            white-space: nowrap;
            box-shadow: 0 2px 8px rgba(29, 78, 216, 0.22);
            display: inline-block;
        }
        .btn-primary-sm:hover {
            background: var(--brand-hover);
            box-shadow: 0 4px 16px rgba(29, 78, 216, 0.32);
            transform: translateY(-1px);
        }
        .mobile-menu-btn {
            display: none;
            background: none;
            border: none;
            cursor: pointer;
            padding: 0.35rem;
            flex-direction: column;
            gap: 5px;
            z-index: 101;
        }
        .mobile-menu-btn span {
            display: block;
            width: 24px;
            height: 2.5px;
            background: var(--dark);
            border-radius: 2px;
            transition: all var(--transition);
        }

        /* ===== 页面标题 ===== */
        .page-hero {
            max-width: 1280px;
            margin: 2rem auto 1.5rem;
            padding: 0 2rem;
            text-align: center;
        }
        .page-hero h1 {
            font-size: 2.4rem;
            font-weight: 800;
            letter-spacing: -0.02em;
            color: var(--dark);
            margin-bottom: 0.5rem;
        }
        .page-hero h1 span {
            background: linear-gradient(135deg, #1d4ed8 0%, #3b82f6 50%, #6366f1 100%);
            background-clip: text;
            -webkit-background-clip: text;
            color: transparent;
        }
        .page-hero .sub {
            color: var(--text-muted);
            font-size: 1.1rem;
            max-width: 650px;
            margin: 0 auto;
        }

        /* ===== 通用section ===== */
        .section {
            max-width: 1280px;
            margin: 4rem auto;
            padding: 2rem;
        }
        .section-header {
            text-align: center;
            margin-bottom: 2.5rem;
        }
        .section-title {
            font-size: 1.9rem;
            font-weight: 700;
            margin-bottom: 0.6rem;
            letter-spacing: -0.02em;
            color: var(--dark);
        }
        .section-sub {
            color: var(--text-muted);
            font-size: 1.05rem;
            max-width: 600px;
            margin: 0 auto;
            line-height: 1.6;
        }

        /* ===== 场景卡片网格 ===== */
        .scenario-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
            gap: 1.8rem;
        }
        @media (max-width: 600px) {
            .scenario-grid {
                grid-template-columns: 1fr;
            }
        }
        .scenario-card {
            background: #fff;
            border-radius: var(--radius-lg);
            overflow: hidden;
            border: 1px solid var(--border-light);
            box-shadow: var(--shadow-sm);
            transition: all var(--transition);
            display: flex;
            flex-direction: column;
            position: relative;
        }
        .scenario-card:hover {
            border-color: #c7d2fe;
            box-shadow: var(--shadow-lg);
            transform: translateY(-3px);
        }
        .scenario-card .card-badge {
            position: absolute;
            top: 1rem;
            right: 1rem;
            background: var(--accent-light);
            color: #b45309;
            padding: 0.25rem 0.9rem;
            border-radius: 30px;
            font-weight: 700;
            font-size: 0.72rem;
            letter-spacing: 0.02em;
            white-space: nowrap;
        }
        .scenario-card .card-body {
            padding: 2rem 1.8rem 1.8rem;
            flex: 1;
        }
        .scenario-card .sc-icon {
            font-size: 2.8rem;
            margin-bottom: 0.8rem;
            display: block;
        }
        .scenario-card h2 {
            font-size: 1.5rem;
            font-weight: 700;
            color: var(--dark);
            margin-bottom: 0.6rem;
            letter-spacing: -0.01em;
        }
        .scenario-card .sc-desc {
            color: #334155;
            font-size: 0.95rem;
            line-height: 1.7;
            margin-bottom: 1.2rem;
        }
        .scenario-card .sc-desc ul {
            list-style: none;
            padding-left: 0;
        }
        .scenario-card .sc-desc ul li {
            margin-bottom: 0.4rem;
            display: flex;
            align-items: baseline;
            gap: 0.4rem;
        }
        .scenario-card .sc-desc ul li::before {
            content: '•';
            color: var(--brand);
            font-weight: 700;
        }
        /* 工具组合区 */
        .tool-combo {
            background: #f8fafc;
            border-radius: var(--radius-sm);
            padding: 1.2rem 1.2rem;
            margin-top: auto;
            border: 1px solid #edf2f7;
        }
        .tool-combo h4 {
            font-size: 0.8rem;
            text-transform: uppercase;
            letter-spacing: 0.04em;
            color: #64748b;
            margin-bottom: 0.7rem;
        }
        .tool-tags {
            display: flex;
            flex-wrap: wrap;
            gap: 0.5rem;
        }
        .tool-tag {
            background: #fff;
            border: 1px solid #e2e8f0;
            padding: 0.4rem 1rem;
            border-radius: 30px;
            font-size: 0.82rem;
            font-weight: 500;
            color: #1e293b;
            text-decoration: none;
            transition: all var(--transition);
            display: inline-flex;
            align-items: center;
            gap: 0.3rem;
        }
        .tool-tag:hover {
            background: var(--brand-light);
            border-color: var(--brand);
            color: var(--brand);
        }
        .tool-tag.primary-tag {
            background: var(--brand);
            color: #fff;
            border-color: var(--brand);
            font-weight: 600;
        }
        .tool-tag.primary-tag:hover {
            background: var(--brand-hover);
        }

        /* ===== 通用CTA ===== */
        .cta-banner {
            background: linear-gradient(110deg, #0f172a 0%, #1e3a5f 45%, #1d4ed8 100%);
            margin: 4rem auto;
            max-width: 1100px;
            border-radius: var(--radius-xl);
            padding: 3rem 2.5rem;
            text-align: center;
            color: #fff;
            position: relative;
            overflow: hidden;
        }
        .cta-banner::before {
            content: '';
            position: absolute;
            top: -60px;
            right: -60px;
            width: 200px;
            height: 200px;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.04);
            pointer-events: none;
        }
        .cta-banner h2 {
            font-size: 1.9rem;
            margin-bottom: 1rem;
            position: relative;
            z-index: 1;
            letter-spacing: -0.02em;
        }
        .cta-banner p {
            margin-bottom: 2rem;
            opacity: 0.9;
            position: relative;
            z-index: 1;
            font-size: 1.05rem;
        }
        .cta-banner .btn-group {
            position: relative;
            z-index: 1;
            display: flex;
            flex-wrap: wrap;
            gap: 1rem;
            justify-content: center;
        }
        .btn-white {
            background: #fff;
            color: #0f172a;
            border: none;
            padding: 0.8rem 2.2rem;
            border-radius: 40px;
            font-weight: 700;
            text-decoration: none;
            transition: all var(--transition);
            font-size: 1rem;
            box-shadow: 0 4px 14px rgba(0, 0, 0, 0.15);
        }
        .btn-white:hover {
            transform: translateY(-2px);
            box-shadow: 0 8px 24px rgba(0, 0, 0, 0.25);
        }
        .btn-outline-light-cta {
            background: transparent;
            border: 2px solid rgba(255, 255, 255, 0.65);
            color: #fff;
            padding: 0.8rem 2.2rem;
            border-radius: 40px;
            font-weight: 600;
            text-decoration: none;
            transition: all var(--transition);
            font-size: 1rem;
        }
        .btn-outline-light-cta:hover {
            background: rgba(255, 255, 255, 0.1);
            border-color: #fff;
        }

        /* ===== FOOTER ===== */
        .footer {
            border-top: 1px solid var(--border);
            margin-top: 4rem;
            background: var(--bg-footer);
        }
        .footer-container {
            max-width: 1280px;
            margin: 0 auto;
            padding: 3rem 2rem 2rem;
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
            gap: 2.5rem;
        }
        .footer-col h4 {
            margin-bottom: 1rem;
            font-size: 1rem;
            font-weight: 700;
            color: var(--dark);
            letter-spacing: -0.01em;
        }
        .footer-col a {
            display: block;
            color: #475569;
            text-decoration: none;
            margin-bottom: 0.65rem;
            font-size: 0.88rem;
            transition: color var(--transition);
        }
        .footer-col a:hover {
            color: var(--brand);
        }
        .copyright {
            text-align: center;
            padding: 1.5rem;
            border-top: 1px solid var(--border);
            font-size: 0.8rem;
            color: var(--text-light);
            letter-spacing: 0.02em;
        }

        /* ===== RESPONSIVE ===== */
        @media (max-width: 900px) {
            .page-hero h1 {
                font-size: 1.9rem;
            }
            .scenario-card .card-body {
                padding: 1.5rem;
            }
        }
        @media (max-width: 680px) {
            .nav-container {
                flex-direction: row;
                flex-wrap: wrap;
                padding: 0.7rem 1.1rem;
            }
            .nav-links {
                display: none;
                width: 100%;
                flex-direction: column;
                gap: 0.3rem;
                background: #fff;
                border-radius: var(--radius-sm);
                padding: 1rem;
                box-shadow: var(--shadow-lg);
                position: absolute;
                top: 100%;
                left: 0;
                right: 0;
                border: 1px solid var(--border);
            }
            .nav-links.open {
                display: flex;
            }
            .mobile-menu-btn {
                display: flex;
            }
            .scenario-grid {
                grid-template-columns: 1fr;
            }
            .section {
                padding: 1.2rem;
            }
        }
        @media (max-width: 400px) {
            .page-hero h1 {
                font-size: 1.6rem;
            }
        }
        @media print {
            .header,
            .footer,
            .cta-banner {
                display: none;
            }
            body {
                color: #000;
                background: #fff;
            }
        }