/* roulang page: index */
:root {
            --primary: #1E90FF;
            --primary-dark: #1a7de6;
            --primary-light: #e8f4fd;
            --accent: #FF6B35;
            --accent-dark: #e55a2b;
            --bg-light: #F8F9FA;
            --bg-dark: #1A1E2C;
            --text-dark: #333333;
            --text-muted: #666666;
            --text-light: #ffffff;
            --border-color: #e8e8e8;
            --radius: 12px;
            --radius-sm: 8px;
            --shadow: 0 4px 12px rgba(0,0,0,0.06);
            --shadow-hover: 0 8px 24px rgba(0,0,0,0.12);
            --shadow-lg: 0 16px 40px rgba(0,0,0,0.10);
            --transition: all 0.3s ease;
            --font-family: 'PingFang SC', '微软雅黑', 'Helvetica Neue', Arial, sans-serif;
            --container-max: 1200px;
            --section-gap: 4rem;
            --inner-gap: 2rem;
        }

        *,
        *::before,
        *::after {
            box-sizing: border-box;
        }

        html {
            scroll-behavior: smooth;
        }

        body {
            font-family: var(--font-family);
            margin: 0;
            padding: 0;
            color: var(--text-dark);
            background: var(--bg-light);
            line-height: 1.7;
            font-size: 1rem;
            -webkit-font-smoothing: antialiased;
        }

        a {
            color: var(--primary);
            text-decoration: none;
            transition: var(--transition);
        }
        a:hover {
            color: var(--primary-dark);
        }
        a:focus-visible {
            outline: 3px solid rgba(30, 144, 255, 0.4);
            outline-offset: 2px;
        }

        img {
            max-width: 100%;
            height: auto;
            display: block;
        }

        ul, ol {
            padding-left: 1.25rem;
        }

        h1, h2, h3, h4, h5, h6 {
            line-height: 1.3;
            margin-top: 0;
            color: var(--text-dark);
        }

        .container {
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 1.5rem;
        }

        .section-padding {
            padding: var(--section-gap) 0;
        }

        .section-title {
            text-align: center;
            margin-bottom: var(--inner-gap);
        }
        .section-title h2 {
            font-size: 2.25rem;
            font-weight: 700;
            color: var(--text-dark);
            margin-bottom: 0.5rem;
            letter-spacing: -0.02em;
        }
        .section-title p {
            font-size: 1rem;
            color: var(--text-muted);
            max-width: 640px;
            margin: 0 auto;
        }

        .btn {
            display: inline-block;
            padding: 12px 28px;
            border-radius: var(--radius-sm);
            font-size: 1rem;
            font-weight: 600;
            line-height: 1.4;
            text-align: center;
            cursor: pointer;
            transition: var(--transition);
            border: 2px solid transparent;
            background: transparent;
            font-family: var(--font-family);
        }
        .btn:focus-visible {
            outline: 3px solid rgba(30, 144, 255, 0.4);
            outline-offset: 2px;
        }

        .btn-primary {
            background: var(--primary);
            color: var(--text-light);
            border-color: var(--primary);
        }
        .btn-primary:hover {
            background: var(--primary-dark);
            border-color: var(--primary-dark);
            color: var(--text-light);
            box-shadow: inset 0 2px 6px rgba(0,0,0,0.15);
            transform: translateY(-2px);
        }
        .btn-primary:active {
            transform: translateY(0);
            box-shadow: inset 0 2px 4px rgba(0,0,0,0.2);
        }

        .btn-outline {
            background: transparent;
            color: var(--text-light);
            border-color: var(--text-light);
        }
        .btn-outline:hover {
            background: var(--text-light);
            color: var(--primary);
            border-color: var(--text-light);
            transform: translateY(-2px);
        }
        .btn-outline:active {
            transform: translateY(0);
        }

        .btn-accent {
            background: var(--accent);
            color: var(--text-light);
            border-color: var(--accent);
        }
        .btn-accent:hover {
            background: var(--accent-dark);
            border-color: var(--accent-dark);
            color: var(--text-light);
            transform: translateY(-2px);
            box-shadow: 0 6px 16px rgba(255, 107, 53, 0.35);
        }
        .btn-accent:active {
            transform: translateY(0);
        }

        .btn-sm {
            padding: 8px 20px;
            font-size: 0.875rem;
        }

        .btn-lg {
            padding: 16px 36px;
            font-size: 1.125rem;
        }

        .card {
            background: #ffffff;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
            transition: var(--transition);
            overflow: hidden;
        }
        .card:hover {
            box-shadow: var(--shadow-hover);
            transform: translateY(-4px);
        }

        .badge {
            display: inline-block;
            padding: 4px 12px;
            border-radius: 20px;
            font-size: 0.75rem;
            font-weight: 600;
            line-height: 1.4;
            background: var(--primary-light);
            color: var(--primary);
        }
        .badge-accent {
            background: rgba(255, 107, 53, 0.12);
            color: var(--accent);
        }
        .badge-dark {
            background: rgba(26, 30, 44, 0.08);
            color: var(--bg-dark);
        }

        .tag {
            display: inline-block;
            padding: 2px 10px;
            border-radius: 4px;
            font-size: 0.75rem;
            font-weight: 500;
            background: var(--bg-light);
            color: var(--text-muted);
            border: 1px solid var(--border-color);
        }

        /* ===== Navigation ===== */
        .site-header {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 1000;
            background: rgba(255, 255, 255, 0.97);
            backdrop-filter: blur(8px);
            -webkit-backdrop-filter: blur(8px);
            border-bottom: 1px solid rgba(0, 0, 0, 0.05);
            height: 70px;
            display: flex;
            align-items: center;
            transition: var(--transition);
        }
        .site-header .container {
            display: flex;
            align-items: center;
            justify-content: center;
            flex-wrap: nowrap;
            width: 100%;
            position: relative;
        }

        .nav-logo {
            font-size: 1.25rem;
            font-weight: 700;
            color: var(--primary);
            letter-spacing: 0.02em;
            white-space: nowrap;
            padding: 0 1.5rem;
            flex-shrink: 0;
        }
        .nav-logo:hover {
            color: var(--primary-dark);
        }

        .nav-left,
        .nav-right {
            display: flex;
            align-items: center;
            gap: 0.25rem;
            flex: 1;
        }
        .nav-left {
            justify-content: flex-end;
        }
        .nav-right {
            justify-content: flex-start;
        }

        .nav-link {
            display: inline-block;
            padding: 0.5rem 1rem;
            font-size: 0.9375rem;
            font-weight: 500;
            color: #555;
            border-radius: var(--radius-sm);
            transition: var(--transition);
            white-space: nowrap;
        }
        .nav-link:hover {
            color: var(--primary);
            background: rgba(30, 144, 255, 0.06);
        }
        .nav-link.active {
            color: var(--primary);
            font-weight: 600;
        }
        .nav-link:focus-visible {
            outline: 3px solid rgba(30, 144, 255, 0.3);
            outline-offset: 2px;
        }

        .nav-cta {
            background: var(--primary);
            color: var(--text-light) !important;
            padding: 0.5rem 1.25rem;
            border-radius: var(--radius-sm);
            font-weight: 600;
        }
        .nav-cta:hover {
            background: var(--primary-dark);
            color: var(--text-light) !important;
        }

        .hamburger {
            display: none;
            background: var(--primary);
            color: var(--text-light);
            border: none;
            width: 40px;
            height: 40px;
            border-radius: 50%;
            font-size: 1.25rem;
            cursor: pointer;
            align-items: center;
            justify-content: center;
            transition: var(--transition);
            position: absolute;
            right: 1rem;
            top: 50%;
            transform: translateY(-50%);
            z-index: 1001;
        }
        .hamburger:hover {
            background: var(--primary-dark);
        }
        .hamburger:focus-visible {
            outline: 3px solid rgba(30, 144, 255, 0.4);
        }

        .mobile-nav {
            display: none;
            position: fixed;
            top: 70px;
            left: 0;
            right: 0;
            background: rgba(255, 255, 255, 0.98);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            box-shadow: 0 8px 32px rgba(0, 0, 0, 0.10);
            padding: 1.5rem;
            z-index: 999;
            border-bottom: 1px solid var(--border-color);
        }
        .mobile-nav.open {
            display: block;
        }
        .mobile-nav .nav-link {
            display: block;
            padding: 0.75rem 1rem;
            font-size: 1rem;
            border-bottom: 1px solid rgba(0, 0, 0, 0.04);
        }
        .mobile-nav .nav-link:last-child {
            border-bottom: none;
        }
        .mobile-nav .nav-cta {
            text-align: center;
            margin-top: 0.5rem;
        }

        /* ===== Hero ===== */
        .hero-section {
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            position: relative;
            background: var(--bg-dark) url('/assets/images/backpic/back-1.webp') center center / cover no-repeat;
            padding: 100px 0 80px;
            overflow: hidden;
        }
        .hero-section::before {
            content: '';
            position: absolute;
            inset: 0;
            background: rgba(0, 0, 0, 0.55);
            z-index: 1;
        }
        .hero-section .container {
            position: relative;
            z-index: 2;
            text-align: center;
        }
        .hero-title {
            font-size: 3rem;
            font-weight: 700;
            color: var(--text-light);
            margin-bottom: 1rem;
            letter-spacing: -0.02em;
            line-height: 1.2;
            text-shadow: 0 2px 12px rgba(0,0,0,0.3);
        }
        .hero-subtitle {
            font-size: 1.325rem;
            color: rgba(255, 255, 255, 0.85);
            margin-bottom: 2rem;
            font-weight: 400;
            max-width: 640px;
            margin-left: auto;
            margin-right: auto;
        }
        .hero-actions {
            display: flex;
            gap: 1rem;
            justify-content: center;
            flex-wrap: wrap;
        }

        /* ===== Timeline ===== */
        .timeline-section {
            background: #ffffff;
        }
        .timeline-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 1.5rem;
            margin-top: 2rem;
        }
        .timeline-step {
            text-align: center;
            padding: 2rem 1.25rem;
            background: var(--bg-light);
            border-radius: var(--radius);
            transition: var(--transition);
            position: relative;
        }
        .timeline-step:hover {
            background: var(--primary-light);
            transform: translateY(-4px);
        }
        .timeline-step .step-icon {
            width: 64px;
            height: 64px;
            border-radius: 50%;
            background: var(--primary);
            color: var(--text-light);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.75rem;
            margin: 0 auto 1rem;
            box-shadow: 0 4px 12px rgba(30, 144, 255, 0.25);
        }
        .timeline-step .step-number {
            font-size: 0.75rem;
            font-weight: 700;
            color: var(--primary);
            text-transform: uppercase;
            letter-spacing: 0.08em;
            margin-bottom: 0.25rem;
        }
        .timeline-step h3 {
            font-size: 1.125rem;
            font-weight: 600;
            margin-bottom: 0.5rem;
        }
        .timeline-step p {
            font-size: 0.875rem;
            color: var(--text-muted);
            margin-bottom: 0;
        }
        .timeline-step::after {
            content: '→';
            position: absolute;
            right: -1rem;
            top: 50%;
            transform: translateY(-50%);
            font-size: 1.5rem;
            color: var(--primary);
            font-weight: 300;
            opacity: 0.4;
        }
        .timeline-step:last-child::after {
            display: none;
        }

        /* ===== Highlights ===== */
        .highlights-section {
            background: var(--bg-light);
        }
        .highlights-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 1.75rem;
            margin-top: 2rem;
        }
        .highlight-card {
            background: #ffffff;
            border-radius: var(--radius);
            padding: 2rem 1.75rem;
            box-shadow: var(--shadow);
            transition: var(--transition);
            text-align: center;
        }
        .highlight-card:hover {
            box-shadow: var(--shadow-hover);
            transform: translateY(-6px);
        }
        .highlight-card .hc-icon {
            width: 72px;
            height: 72px;
            border-radius: 50%;
            background: var(--primary-light);
            color: var(--primary);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 2rem;
            margin: 0 auto 1.25rem;
            transition: var(--transition);
        }
        .highlight-card:hover .hc-icon {
            background: var(--primary);
            color: var(--text-light);
        }
        .highlight-card h3 {
            font-size: 1.25rem;
            font-weight: 600;
            margin-bottom: 0.5rem;
        }
        .highlight-card p {
            font-size: 0.9375rem;
            color: var(--text-muted);
            margin-bottom: 0;
        }
        .highlight-card .hc-img {
            width: 100%;
            height: 160px;
            object-fit: cover;
            border-radius: var(--radius-sm);
            margin-bottom: 1.25rem;
        }

        /* ===== Pricing / Plans ===== */
        .pricing-section {
            background: #ffffff;
        }
        .pricing-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 1.5rem;
            margin-top: 2rem;
        }
        .pricing-card {
            background: #ffffff;
            border: 2px solid var(--border-color);
            border-radius: var(--radius);
            padding: 2rem 1.5rem;
            text-align: center;
            transition: var(--transition);
            position: relative;
        }
        .pricing-card:hover {
            border-color: var(--primary);
            box-shadow: var(--shadow-hover);
            transform: translateY(-4px);
        }
        .pricing-card .pc-label {
            font-size: 0.75rem;
            font-weight: 700;
            text-transform: uppercase;
            letter-spacing: 0.1em;
            color: var(--text-muted);
            margin-bottom: 0.25rem;
        }
        .pricing-card .pc-name {
            font-size: 1.5rem;
            font-weight: 700;
            margin-bottom: 0.5rem;
        }
        .pricing-card .pc-price {
            font-size: 2.25rem;
            font-weight: 700;
            color: var(--primary);
            margin-bottom: 1rem;
        }
        .pricing-card .pc-price small {
            font-size: 1rem;
            color: var(--text-muted);
            font-weight: 400;
        }
        .pricing-card .pc-features {
            list-style: none;
            padding: 0;
            margin: 0 0 1.5rem;
            text-align: left;
        }
        .pricing-card .pc-features li {
            padding: 0.5rem 0;
            font-size: 0.9375rem;
            color: var(--text-dark);
            border-bottom: 1px solid rgba(0,0,0,0.04);
            display: flex;
            align-items: center;
            gap: 0.5rem;
        }
        .pricing-card .pc-features li i {
            color: var(--primary);
            font-size: 0.875rem;
            width: 18px;
        }
        .pricing-card .pc-badge {
            position: absolute;
            top: -12px;
            right: 20px;
            background: var(--accent);
            color: var(--text-light);
            padding: 4px 14px;
            border-radius: 20px;
            font-size: 0.75rem;
            font-weight: 600;
        }
        .pricing-card.featured {
            border-color: var(--primary);
            box-shadow: 0 4px 20px rgba(30, 144, 255, 0.12);
        }

        /* ===== CTA Form ===== */
        .cta-section {
            background: var(--bg-dark) url('/assets/images/backpic/back-2.webp') center center / cover no-repeat;
            position: relative;
            padding: var(--section-gap) 0;
        }
        .cta-section::before {
            content: '';
            position: absolute;
            inset: 0;
            background: rgba(26, 30, 44, 0.78);
            z-index: 1;
        }
        .cta-section .container {
            position: relative;
            z-index: 2;
        }
        .cta-section .section-title h2 {
            color: var(--text-light);
        }
        .cta-section .section-title p {
            color: rgba(255, 255, 255, 0.7);
        }

        .cta-form-wrap {
            max-width: 640px;
            margin: 2rem auto 0;
            background: rgba(255, 255, 255, 0.95);
            border-radius: var(--radius);
            padding: 2.5rem 2rem;
            box-shadow: var(--shadow-lg);
        }
        .cta-form-wrap .form-row {
            margin-bottom: 1.25rem;
        }
        .cta-form-wrap label {
            font-size: 0.875rem;
            font-weight: 600;
            color: var(--text-dark);
            margin-bottom: 0.25rem;
            display: block;
        }
        .cta-form-wrap input,
        .cta-form-wrap select {
            width: 100%;
            height: 48px;
            padding: 0 1rem;
            border: 2px solid #d0d0d0;
            border-radius: var(--radius-sm);
            font-size: 1rem;
            font-family: var(--font-family);
            transition: var(--transition);
            background: #ffffff;
            color: var(--text-dark);
        }
        .cta-form-wrap input:focus,
        .cta-form-wrap select:focus {
            border-color: var(--primary);
            outline: none;
            box-shadow: 0 0 0 3px rgba(30, 144, 255, 0.2);
        }
        .cta-form-wrap input::placeholder {
            color: #aaa;
        }
        .cta-form-wrap .btn {
            width: 100%;
            margin-top: 0.5rem;
        }

        /* ===== CMS News ===== */
        .news-section {
            background: var(--bg-light);
        }
        .news-list {
            display: flex;
            flex-direction: column;
            gap: 1.25rem;
            margin-top: 2rem;
        }
        .news-item {
            display: flex;
            gap: 1.5rem;
            background: #ffffff;
            border-radius: var(--radius);
            padding: 1.25rem;
            box-shadow: var(--shadow);
            transition: var(--transition);
            align-items: flex-start;
        }
        .news-item:hover {
            box-shadow: var(--shadow-hover);
            transform: translateY(-2px);
        }
        .news-item .ni-img {
            width: 200px;
            min-height: 120px;
            border-radius: var(--radius-sm);
            object-fit: cover;
            flex-shrink: 0;
            background: var(--bg-light);
        }
        .news-item .ni-content {
            flex: 1;
        }
        .news-item .ni-title {
            font-size: 1.125rem;
            font-weight: 600;
            margin-bottom: 0.375rem;
            color: var(--text-dark);
            transition: var(--transition);
        }
        .news-item .ni-title a {
            color: inherit;
        }
        .news-item .ni-title a:hover {
            color: var(--primary);
        }
        .news-item .ni-meta {
            font-size: 0.8125rem;
            color: var(--text-muted);
            margin-bottom: 0.5rem;
            display: flex;
            gap: 1rem;
            align-items: center;
        }
        .news-item .ni-meta .ni-cat {
            background: var(--primary-light);
            color: var(--primary);
            padding: 2px 10px;
            border-radius: 12px;
            font-size: 0.75rem;
            font-weight: 500;
        }
        .news-item .ni-excerpt {
            font-size: 0.9375rem;
            color: var(--text-muted);
            margin-bottom: 0;
            line-height: 1.6;
        }
        .news-empty {
            text-align: center;
            padding: 3rem 1rem;
            color: var(--text-muted);
            font-size: 1rem;
            background: #ffffff;
            border-radius: var(--radius);
            box-shadow: var(--shadow);
        }
        .news-empty i {
            font-size: 2.5rem;
            color: #ccc;
            margin-bottom: 1rem;
            display: block;
        }

        /* ===== FAQ ===== */
        .faq-section {
            background: #ffffff;
        }
        .faq-list {
            max-width: 800px;
            margin: 2rem auto 0;
            display: flex;
            flex-direction: column;
            gap: 0.75rem;
        }
        .faq-item {
            border: 1px solid var(--border-color);
            border-radius: var(--radius-sm);
            overflow: hidden;
            transition: var(--transition);
        }
        .faq-item:hover {
            border-color: var(--primary);
        }
        .faq-item .faq-q {
            padding: 1rem 1.5rem;
            font-size: 1rem;
            font-weight: 600;
            cursor: pointer;
            display: flex;
            justify-content: space-between;
            align-items: center;
            background: #fafafa;
            transition: var(--transition);
            user-select: none;
        }
        .faq-item .faq-q:hover {
            background: var(--primary-light);
        }
        .faq-item .faq-q i {
            transition: transform 0.3s ease;
            color: var(--primary);
            font-size: 0.875rem;
        }
        .faq-item.open .faq-q i {
            transform: rotate(180deg);
        }
        .faq-item .faq-a {
            padding: 0 1.5rem;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease, padding 0.3s ease;
            background: #ffffff;
        }
        .faq-item.open .faq-a {
            max-height: 300px;
            padding: 1rem 1.5rem 1.5rem;
        }
        .faq-item .faq-a p {
            margin: 0;
            font-size: 0.9375rem;
            color: var(--text-muted);
            line-height: 1.7;
        }

        /* ===== Footer ===== */
        .site-footer {
            background: var(--bg-dark);
            color: rgba(255, 255, 255, 0.7);
            padding: 3rem 0 1.5rem;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 2rem;
            margin-bottom: 2rem;
        }
        .footer-grid h4 {
            font-size: 1rem;
            font-weight: 600;
            color: var(--text-light);
            margin-bottom: 1rem;
        }
        .footer-grid p,
        .footer-grid a {
            font-size: 0.875rem;
            color: rgba(255, 255, 255, 0.6);
            line-height: 1.8;
            display: block;
        }
        .footer-grid a:hover {
            color: var(--primary);
        }
        .footer-grid .footer-logo {
            font-size: 1.125rem;
            font-weight: 700;
            color: var(--text-light);
            margin-bottom: 0.5rem;
        }
        .footer-grid .footer-logo:hover {
            color: var(--primary);
        }
        .footer-social {
            display: flex;
            gap: 0.75rem;
            margin-top: 0.75rem;
        }
        .footer-social a {
            width: 38px;
            height: 38px;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.08);
            color: rgba(255, 255, 255, 0.6);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1rem;
            transition: var(--transition);
        }
        .footer-social a:hover {
            background: var(--primary);
            color: var(--text-light);
            transform: translateY(-2px);
        }
        .footer-bottom {
            border-top: 1px solid rgba(255, 255, 255, 0.08);
            padding-top: 1.5rem;
            text-align: center;
            font-size: 0.8125rem;
            color: rgba(255, 255, 255, 0.4);
        }
        .footer-bottom a {
            color: rgba(255, 255, 255, 0.5);
        }
        .footer-bottom a:hover {
            color: var(--primary);
        }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .timeline-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .timeline-step::after {
                display: none;
            }
            .pricing-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .highlights-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .footer-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .hero-title {
                font-size: 2.5rem;
            }
            .hero-subtitle {
                font-size: 1.125rem;
            }
            .section-title h2 {
                font-size: 1.875rem;
            }
            .news-item .ni-img {
                width: 160px;
                min-height: 100px;
            }
        }

        @media (max-width: 768px) {
            .nav-left,
            .nav-right {
                display: none;
            }
            .hamburger {
                display: flex;
            }
            .site-header .container {
                justify-content: flex-start;
                padding-left: 1rem;
            }
            .nav-logo {
                font-size: 1.1rem;
                padding: 0;
            }
            .hero-title {
                font-size: 2rem;
            }
            .hero-subtitle {
                font-size: 1rem;
            }
            .hero-actions .btn {
                padding: 10px 22px;
                font-size: 0.9375rem;
            }
            .timeline-grid {
                grid-template-columns: 1fr;
            }
            .pricing-grid {
                grid-template-columns: 1fr;
            }
            .highlights-grid {
                grid-template-columns: 1fr;
            }
            .news-item {
                flex-direction: column;
            }
            .news-item .ni-img {
                width: 100%;
                min-height: 180px;
            }
            .footer-grid {
                grid-template-columns: 1fr;
                gap: 1.5rem;
            }
            .cta-form-wrap {
                padding: 1.5rem;
            }
            .section-padding {
                padding: 2.5rem 0;
            }
            :root {
                --section-gap: 2.5rem;
            }
        }

        @media (max-width: 520px) {
            .hero-title {
                font-size: 1.65rem;
            }
            .hero-subtitle {
                font-size: 0.9375rem;
            }
            .hero-actions {
                flex-direction: column;
                align-items: center;
            }
            .hero-actions .btn {
                width: 100%;
                max-width: 280px;
            }
            .section-title h2 {
                font-size: 1.5rem;
            }
            .pricing-card .pc-price {
                font-size: 1.75rem;
            }
            .cta-form-wrap {
                padding: 1.25rem;
            }
            .news-item .ni-img {
                min-height: 140px;
            }
        }

        /* ===== Back to Top ===== */
        .back-top {
            position: fixed;
            bottom: 2rem;
            right: 2rem;
            width: 48px;
            height: 48px;
            border-radius: 50%;
            background: var(--primary);
            color: var(--text-light);
            border: none;
            font-size: 1.25rem;
            cursor: pointer;
            box-shadow: 0 4px 16px rgba(30, 144, 255, 0.3);
            transition: var(--transition);
            z-index: 999;
            display: flex;
            align-items: center;
            justify-content: center;
            opacity: 0;
            visibility: hidden;
            transform: translateY(20px);
        }
        .back-top.visible {
            opacity: 1;
            visibility: visible;
            transform: translateY(0);
        }
        .back-top:hover {
            background: var(--primary-dark);
            transform: translateY(-4px);
            box-shadow: 0 6px 20px rgba(30, 144, 255, 0.4);
        }
        .back-top:focus-visible {
            outline: 3px solid rgba(30, 144, 255, 0.4);
        }

/* roulang page: article */
/* ===== 设计变量 ===== */
        :root {
            --primary: #1E90FF;
            --primary-dark: #1878D6;
            --primary-light: #4AACFF;
            --accent: #FF6B35;
            --accent-dark: #E55A2B;
            --bg-light: #F8F9FA;
            --bg-dark: #1A1E2C;
            --text-dark: #1A1E2C;
            --text-body: #333333;
            --text-muted: #666666;
            --text-light: #888888;
            --white: #FFFFFF;
            --border: #E8E8E8;
            --radius: 8px;
            --radius-lg: 12px;
            --shadow-sm: 0 2px 8px rgba(0,0,0,0.05);
            --shadow: 0 4px 12px rgba(0,0,0,0.06);
            --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);
            --shadow-hover: 0 12px 32px rgba(0,0,0,0.15);
            --transition: all 0.3s ease;
            --font-base: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', Arial, sans-serif;
            --container-max: 1200px;
            --header-height: 70px;
        }

        /* ===== Reset & Base ===== */
        *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
        html { scroll-behavior: smooth; }
        body {
            font-family: var(--font-base);
            font-size: 16px;
            line-height: 1.7;
            color: var(--text-body);
            background: var(--bg-light);
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }
        a { color: var(--primary); text-decoration: none; transition: var(--transition); }
        a:hover { color: var(--primary-dark); }
        img { max-width: 100%; height: auto; display: block; }
        ul, ol { list-style: none; }
        .container { max-width: var(--container-max); margin: 0 auto; padding: 0 24px; }
        @media screen and (max-width: 640px) { .container { padding: 0 16px; } }

        /* ===== Header / Nav (居中Logo + 两侧导航) ===== */
        .site-header {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: var(--header-height);
            background: var(--white);
            border-bottom: 1px solid var(--border);
            z-index: 1000;
            box-shadow: 0 1px 4px rgba(0,0,0,0.04);
        }
        .site-header .container {
            display: flex;
            align-items: center;
            justify-content: space-between;
            height: 100%;
            position: relative;
        }
        .nav-left, .nav-right {
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .nav-left .nav-link, .nav-right .nav-link {
            font-size: 0.95rem;
            color: var(--text-muted);
            padding: 6px 16px;
            border-radius: var(--radius);
            transition: var(--transition);
            font-weight: 500;
            white-space: nowrap;
        }
        .nav-left .nav-link:hover, .nav-right .nav-link:hover,
        .nav-left .nav-link.active, .nav-right .nav-link.active {
            color: var(--primary);
            background: rgba(30,144,255,0.08);
        }
        .nav-logo {
            font-size: 1.25rem;
            font-weight: 700;
            color: var(--text-dark);
            letter-spacing: 0.5px;
            white-space: nowrap;
            transition: var(--transition);
            text-align: center;
            flex-shrink: 0;
            margin: 0 12px;
        }
        .nav-logo:hover { color: var(--primary); }
        .nav-cta {
            background: var(--primary) !important;
            color: var(--white) !important;
            padding: 8px 22px !important;
            border-radius: var(--radius) !important;
            font-weight: 600;
        }
        .nav-cta:hover { background: var(--primary-dark) !important; color: var(--white) !important; transform: translateY(-1px); box-shadow: 0 4px 12px rgba(30,144,255,0.3); }
        .hamburger {
            display: none;
            background: var(--primary);
            border: none;
            color: var(--white);
            width: 40px;
            height: 40px;
            border-radius: var(--radius);
            font-size: 1.2rem;
            cursor: pointer;
            align-items: center;
            justify-content: center;
            transition: var(--transition);
            flex-shrink: 0;
        }
        .hamburger:hover { background: var(--primary-dark); }
        @media screen and (max-width: 1024px) {
            .nav-left .nav-link, .nav-right .nav-link { font-size: 0.85rem; padding: 6px 10px; }
            .nav-logo { font-size: 1.1rem; }
        }
        @media screen and (max-width: 768px) {
            .hamburger { display: flex; order: 1; }
            .nav-left { display: none; }
            .nav-right { display: none; }
            .nav-logo { order: 2; margin: 0 auto; font-size: 1.1rem; }
            .site-header .container { justify-content: flex-start; }
            .nav-logo { margin-left: auto; margin-right: auto; position: absolute; left: 50%; transform: translateX(-50%); }
            .mobile-menu-open .nav-left,
            .mobile-menu-open .nav-right {
                display: flex;
                flex-direction: column;
                position: absolute;
                top: var(--header-height);
                left: 0;
                width: 100%;
                background: var(--white);
                border-bottom: 1px solid var(--border);
                box-shadow: var(--shadow-lg);
                padding: 16px 24px;
                gap: 4px;
                z-index: 999;
            }
            .mobile-menu-open .nav-left { order: 3; }
            .mobile-menu-open .nav-right { order: 4; top: calc(var(--header-height) + 180px); }
            .mobile-menu-open .nav-left .nav-link,
            .mobile-menu-open .nav-right .nav-link {
                padding: 12px 16px;
                width: 100%;
                border-radius: var(--radius);
            }
            .mobile-menu-open .nav-cta { text-align: center; }
        }
        @media screen and (max-width: 480px) {
            .nav-logo { font-size: 0.95rem; }
        }

        /* ===== 面包屑 ===== */
        .breadcrumb {
            padding: 90px 0 0;
            background: var(--white);
            border-bottom: 1px solid var(--border);
        }
        .breadcrumb .container {
            display: flex;
            align-items: center;
            flex-wrap: wrap;
            gap: 6px;
            padding-top: 14px;
            padding-bottom: 14px;
            font-size: 0.875rem;
            color: var(--text-light);
        }
        .breadcrumb a { color: var(--text-muted); }
        .breadcrumb a:hover { color: var(--primary); }
        .breadcrumb .sep { color: #ccc; margin: 0 4px; }
        .breadcrumb .current { color: var(--text-body); font-weight: 500; }

        /* ===== 文章主体 ===== */
        .article-main {
            padding: 48px 0 64px;
            background: var(--white);
        }
        .article-wrapper {
            max-width: 800px;
            margin: 0 auto;
        }
        .article-header {
            margin-bottom: 36px;
            text-align: center;
        }
        .article-header h1 {
            font-size: 2rem;
            font-weight: 700;
            color: var(--text-dark);
            line-height: 1.3;
            margin-bottom: 16px;
        }
        .article-meta {
            display: flex;
            justify-content: center;
            align-items: center;
            gap: 20px;
            font-size: 0.9rem;
            color: var(--text-light);
            flex-wrap: wrap;
        }
        .article-meta i { margin-right: 4px; }
        .article-meta .category-badge {
            background: rgba(30,144,255,0.1);
            color: var(--primary);
            padding: 4px 14px;
            border-radius: 20px;
            font-size: 0.8rem;
            font-weight: 500;
        }
        .article-featured-img {
            margin-bottom: 36px;
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: var(--shadow);
        }
        .article-featured-img img { width: 100%; height: auto; object-fit: cover; }
        .article-content {
            font-size: 1.05rem;
            line-height: 1.85;
            color: var(--text-body);
        }
        .article-content h2 { font-size: 1.6rem; font-weight: 700; margin: 36px 0 16px; color: var(--text-dark); }
        .article-content h3 { font-size: 1.3rem; font-weight: 600; margin: 28px 0 12px; color: var(--text-dark); }
        .article-content p { margin-bottom: 18px; }
        .article-content ul, .article-content ol { margin: 16px 0 20px; padding-left: 24px; }
        .article-content ul li { list-style: disc; margin-bottom: 8px; }
        .article-content ol li { list-style: decimal; margin-bottom: 8px; }
        .article-content blockquote {
            border-left: 4px solid var(--primary);
            background: rgba(30,144,255,0.05);
            padding: 16px 24px;
            margin: 24px 0;
            border-radius: 0 var(--radius) var(--radius) 0;
            color: var(--text-muted);
            font-style: italic;
        }
        .article-content img { border-radius: var(--radius); margin: 24px auto; box-shadow: var(--shadow-sm); }
        .article-content a { color: var(--primary); text-decoration: underline; }
        .article-content a:hover { color: var(--primary-dark); }
        .not-found {
            text-align: center;
            padding: 80px 20px;
        }
        .not-found h2 { font-size: 2rem; color: var(--text-dark); margin-bottom: 16px; }
        .not-found p { color: var(--text-muted); margin-bottom: 24px; }
        .not-found .btn-back { display: inline-block; padding: 12px 32px; background: var(--primary); color: var(--white); border-radius: var(--radius); font-weight: 600; }
        .not-found .btn-back:hover { background: var(--primary-dark); color: var(--white); }

        /* ===== 相关推荐 ===== */
        .related-section {
            background: var(--bg-light);
            padding: 48px 0 64px;
        }
        .related-section h2 {
            text-align: center;
            font-size: 1.75rem;
            font-weight: 700;
            color: var(--text-dark);
            margin-bottom: 36px;
        }
        .related-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
        }
        .related-card {
            background: var(--white);
            border-radius: var(--radius-lg);
            overflow: hidden;
            box-shadow: var(--shadow);
            transition: var(--transition);
        }
        .related-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-4px); }
        .related-card img { width: 100%; height: 160px; object-fit: cover; }
        .related-card-body { padding: 16px 18px 20px; }
        .related-card-body h3 { font-size: 1rem; font-weight: 600; color: var(--text-dark); margin-bottom: 8px; line-height: 1.4; }
        .related-card-body h3 a { color: var(--text-dark); }
        .related-card-body h3 a:hover { color: var(--primary); }
        .related-card-body p { font-size: 0.85rem; color: var(--text-muted); line-height: 1.5; margin-bottom: 0; }
        @media screen and (max-width: 1024px) {
            .related-grid { grid-template-columns: repeat(2, 1fr); }
        }
        @media screen and (max-width: 640px) {
            .related-grid { grid-template-columns: 1fr; }
            .article-header h1 { font-size: 1.5rem; }
        }

        /* ===== Footer ===== */
        .site-footer {
            background: var(--bg-dark);
            color: rgba(255,255,255,0.8);
            padding: 56px 0 0;
            font-size: 0.95rem;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: 1.2fr 1fr 1fr 1.2fr;
            gap: 40px;
            margin-bottom: 40px;
        }
        .footer-logo {
            font-size: 1.3rem;
            font-weight: 700;
            color: var(--white);
            display: inline-block;
            margin-bottom: 16px;
        }
        .footer-logo:hover { color: var(--primary-light); }
        .site-footer p { margin-bottom: 10px; line-height: 1.6; color: rgba(255,255,255,0.65); }
        .site-footer h4 { color: var(--white); font-size: 1.05rem; font-weight: 600; margin-bottom: 18px; }
        .site-footer a { color: rgba(255,255,255,0.7); transition: var(--transition); }
        .site-footer a:hover { color: var(--primary-light); }
        .footer-social { display: flex; gap: 12px; margin-top: 16px; }
        .footer-social a {
            width: 40px; height: 40px;
            border-radius: 50%;
            background: rgba(255,255,255,0.08);
            display: flex; align-items: center; justify-content: center;
            color: rgba(255,255,255,0.7);
            font-size: 1.1rem;
            transition: var(--transition);
        }
        .footer-social a:hover { background: var(--primary); color: var(--white); transform: translateY(-2px); }
        .footer-grid h4 + a { display: block; margin-bottom: 8px; }
        .footer-bottom {
            border-top: 1px solid rgba(255,255,255,0.08);
            padding: 20px 0;
            text-align: center;
            font-size: 0.85rem;
            color: rgba(255,255,255,0.5);
        }
        .footer-bottom a { color: rgba(255,255,255,0.6); }
        .footer-bottom a:hover { color: var(--primary-light); }
        @media screen and (max-width: 1024px) {
            .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; }
        }
        @media screen and (max-width: 640px) {
            .footer-grid { grid-template-columns: 1fr; gap: 24px; }
            .site-footer { padding: 40px 0 0; }
        }

        /* ===== 通用工具 ===== */
        .text-center { text-align: center; }
        .mt-1 { margin-top: 8px; }
        .mt-2 { margin-top: 16px; }
        .mt-3 { margin-top: 24px; }
        .mb-2 { margin-bottom: 16px; }
        .mb-3 { margin-bottom: 24px; }

        /* ===== 响应式微调 ===== */
        @media screen and (max-width: 640px) {
            .article-wrapper { padding: 0; }
            .article-meta { gap: 12px; font-size: 0.8rem; }
            .breadcrumb .container { font-size: 0.8rem; }
            .related-section h2 { font-size: 1.4rem; }
        }

/* roulang page: category2 */
:root {
            --primary: #1E90FF;
            --primary-dark: #1a7de6;
            --primary-light: #e8f4ff;
            --accent: #FF6B35;
            --accent-light: #fff0e8;
            --bg-light: #F8F9FA;
            --bg-dark: #1A1E2C;
            --text-dark: #1a1a2e;
            --text-body: #333333;
            --text-muted: #6b7280;
            --text-light: #f0f4f8;
            --border: #e5e7eb;
            --radius: 12px;
            --radius-sm: 8px;
            --shadow: 0 4px 12px rgba(0,0,0,0.06);
            --shadow-hover: 0 8px 24px rgba(0,0,0,0.12);
            --shadow-lg: 0 12px 36px rgba(0,0,0,0.15);
            --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
            --font-sans: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', system-ui, -apple-system, sans-serif;
            --max-width: 1200px;
            --header-height: 70px;
        }
        *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
        html { scroll-behavior: smooth; font-size: 16px; }
        body {
            font-family: var(--font-sans);
            color: var(--text-body);
            background: var(--bg-light);
            line-height: 1.7;
            -webkit-font-smoothing: antialiased;
        }
        a { color: var(--primary); text-decoration: none; transition: var(--transition); }
        a:hover { color: var(--primary-dark); }
        img { max-width: 100%; height: auto; display: block; }
        ul, ol { list-style: none; }
        .container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }
        section { padding: 5rem 0; }
        .section-title { text-align: center; margin-bottom: 3.5rem; }
        .section-title h2 { font-size: 2.25rem; font-weight: 700; color: var(--text-dark); line-height: 1.3; margin-bottom: 0.75rem; }
        .section-title p { font-size: 1.1rem; color: var(--text-muted); max-width: 700px; margin: 0 auto; }
        .text-center { text-align: center; }
        .mt-1 { margin-top: 1rem; }
        .mb-1 { margin-bottom: 1rem; }
        .mb-2 { margin-bottom: 2rem; }

        /* ===== Header / Nav ===== */
        .site-header {
            position: fixed; top: 0; left: 0; right: 0;
            height: var(--header-height);
            background: rgba(255,255,255,0.97);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid rgba(0,0,0,0.06);
            z-index: 1000;
            transition: var(--transition);
        }
        .site-header .container {
            display: flex; align-items: center; justify-content: center;
            height: 100%; position: relative;
        }
        .nav-left, .nav-right { display: flex; align-items: center; gap: 0.25rem; }
        .nav-left { position: absolute; left: 24px; top: 50%; transform: translateY(-50%); }
        .nav-right { position: absolute; right: 24px; top: 50%; transform: translateY(-50%); }
        .nav-logo {
            font-size: 1.25rem; font-weight: 800; color: var(--primary);
            letter-spacing: 0.5px; white-space: nowrap;
            transition: var(--transition);
        }
        .nav-logo:hover { color: var(--primary-dark); transform: scale(1.02); }
        .nav-link {
            font-size: 0.95rem; font-weight: 500; color: #555;
            padding: 0.5rem 1rem; border-radius: var(--radius-sm);
            transition: var(--transition); position: relative;
        }
        .nav-link:hover { color: var(--primary); background: var(--primary-light); }
        .nav-link.active { color: var(--primary); font-weight: 600; }
        .nav-link.active::after {
            content: ''; position: absolute; bottom: 2px; left: 1rem; right: 1rem;
            height: 2px; background: var(--primary); border-radius: 2px;
        }
        .nav-cta {
            background: var(--primary); color: #fff !important;
            padding: 0.5rem 1.5rem; border-radius: 50px;
            font-weight: 600; font-size: 0.9rem;
        }
        .nav-cta:hover { background: var(--primary-dark); transform: translateY(-1px); box-shadow: 0 4px 12px rgba(30,144,255,0.35); }
        .hamburger {
            display: none; background: none; border: none; font-size: 1.5rem;
            color: var(--primary); cursor: pointer; padding: 0.5rem;
            position: absolute; left: 16px; top: 50%; transform: translateY(-50%);
            z-index: 1001;
        }
        .hamburger:focus { outline: 2px solid var(--primary); outline-offset: 2px; }

        /* ===== Hero ===== */
        .hero-section {
            position: relative; min-height: 70vh;
            display: flex; align-items: center; justify-content: center;
            background: linear-gradient(135deg, #0b1a2e 0%, #1a2d44 50%, #0d1f33 100%);
            overflow: hidden; margin-top: var(--header-height);
        }
        .hero-section::before {
            content: ''; position: absolute; inset: 0;
            background: url('/assets/images/backpic/back-2.webp') center center / cover no-repeat;
            opacity: 0.25; z-index: 0;
        }
        .hero-section::after {
            content: ''; position: absolute; inset: 0;
            background: linear-gradient(135deg, rgba(26,30,44,0.85) 0%, rgba(26,30,44,0.65) 100%);
            z-index: 1;
        }
        .hero-overlay {
            position: absolute; inset: 0;
            background: radial-gradient(ellipse at 30% 50%, rgba(30,144,255,0.15) 0%, transparent 70%);
            z-index: 1;
        }
        .hero-content { position: relative; z-index: 2; text-align: center; max-width: 850px; padding: 2rem 24px; }
        .hero-content .badge {
            display: inline-block; background: rgba(255,107,53,0.2); color: var(--accent);
            padding: 0.4rem 1.2rem; border-radius: 50px; font-size: 0.85rem; font-weight: 600;
            margin-bottom: 1.5rem; border: 1px solid rgba(255,107,53,0.3);
            backdrop-filter: blur(4px);
        }
        .hero-content h1 {
            font-size: 3.2rem; font-weight: 800; color: #fff;
            line-height: 1.2; margin-bottom: 1.2rem;
            text-shadow: 0 2px 20px rgba(0,0,0,0.3);
        }
        .hero-content h1 span { color: var(--primary); }
        .hero-content .subtitle {
            font-size: 1.15rem; color: rgba(255,255,255,0.8);
            max-width: 650px; margin: 0 auto 2rem; line-height: 1.8;
        }
        .hero-actions { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }
        .btn-primary, .btn-outline {
            display: inline-flex; align-items: center; gap: 0.5rem;
            padding: 0.9rem 2.2rem; border-radius: 50px;
            font-size: 1rem; font-weight: 600; border: none;
            cursor: pointer; transition: var(--transition);
            text-decoration: none;
        }
        .btn-primary {
            background: var(--primary); color: #fff;
            box-shadow: 0 4px 16px rgba(30,144,255,0.35);
        }
        .btn-primary:hover { background: var(--primary-dark); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(30,144,255,0.45); color: #fff; }
        .btn-outline {
            background: transparent; color: #fff;
            border: 2px solid rgba(255,255,255,0.6);
        }
        .btn-outline:hover { background: rgba(255,255,255,0.1); border-color: #fff; transform: translateY(-2px); color: #fff; }

        /* ===== Security Features ===== */
        .features-section { background: #fff; }
        .features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 2rem; }
        .feature-card {
            background: var(--bg-light); border-radius: var(--radius);
            padding: 2.5rem 2rem; text-align: center;
            transition: var(--transition); border: 1px solid var(--border);
            position: relative; overflow: hidden;
        }
        .feature-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); border-color: var(--primary); }
        .feature-card .icon {
            width: 64px; height: 64px; border-radius: 16px;
            background: var(--primary-light); color: var(--primary);
            display: flex; align-items: center; justify-content: center;
            font-size: 1.8rem; margin: 0 auto 1.2rem;
            transition: var(--transition);
        }
        .feature-card:hover .icon { background: var(--primary); color: #fff; transform: scale(1.05); }
        .feature-card h3 { font-size: 1.25rem; font-weight: 700; color: var(--text-dark); margin-bottom: 0.6rem; }
        .feature-card p { font-size: 0.95rem; color: var(--text-muted); line-height: 1.7; }

        /* ===== Security Architecture ===== */
        .architecture-section { background: var(--bg-light); }
        .arch-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 2rem; }
        .arch-item {
            display: flex; gap: 1.5rem; align-items: flex-start;
            background: #fff; border-radius: var(--radius);
            padding: 2rem; border: 1px solid var(--border);
            transition: var(--transition);
        }
        .arch-item:hover { box-shadow: var(--shadow-hover); transform: translateY(-2px); }
        .arch-item .num {
            flex-shrink: 0; width: 48px; height: 48px;
            border-radius: 50%; background: var(--primary-light);
            color: var(--primary); font-size: 1.2rem; font-weight: 700;
            display: flex; align-items: center; justify-content: center;
        }
        .arch-item h4 { font-size: 1.1rem; font-weight: 700; color: var(--text-dark); margin-bottom: 0.4rem; }
        .arch-item p { font-size: 0.92rem; color: var(--text-muted); line-height: 1.7; }

        /* ===== Data Protection ===== */
        .protection-section {
            background: linear-gradient(135deg, var(--bg-dark) 0%, #0f1a2e 100%);
            color: #fff;
        }
        .protection-section .section-title h2 { color: #fff; }
        .protection-section .section-title p { color: rgba(255,255,255,0.7); }
        .protection-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.5rem; }
        .protection-card {
            background: rgba(255,255,255,0.06);
            backdrop-filter: blur(8px);
            border: 1px solid rgba(255,255,255,0.08);
            border-radius: var(--radius); padding: 2rem 1.5rem;
            text-align: center; transition: var(--transition);
        }
        .protection-card:hover { background: rgba(255,255,255,0.1); transform: translateY(-4px); }
        .protection-card .icon { font-size: 2.2rem; color: var(--accent); margin-bottom: 1rem; }
        .protection-card h4 { font-size: 1.1rem; font-weight: 700; margin-bottom: 0.5rem; }
        .protection-card p { font-size: 0.9rem; color: rgba(255,255,255,0.7); line-height: 1.6; }

        /* ===== Stats ===== */
        .stats-section { background: #fff; padding: 4rem 0; }
        .stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 2rem; text-align: center; }
        .stat-item .num { font-size: 2.8rem; font-weight: 800; color: var(--primary); line-height: 1.2; }
        .stat-item .num span { font-size: 1.6rem; }
        .stat-item .label { font-size: 0.95rem; color: var(--text-muted); margin-top: 0.4rem; }

        /* ===== FAQ ===== */
        .faq-section { background: #fff; }
        .faq-list { max-width: 800px; margin: 0 auto; }
        .faq-item {
            border: 1px solid var(--border); border-radius: var(--radius);
            margin-bottom: 0.75rem; overflow: hidden;
            transition: var(--transition);
        }
        .faq-item:hover { border-color: var(--primary); }
        .faq-question {
            display: flex; align-items: center; justify-content: space-between;
            padding: 1.2rem 1.5rem; cursor: pointer;
            font-size: 1.05rem; font-weight: 600; color: var(--text-dark);
            background: var(--bg-light); transition: var(--transition);
            border: none; width: 100%; text-align: left;
            font-family: var(--font-sans);
        }
        .faq-question:hover { background: var(--primary-light); }
        .faq-question .arrow { transition: var(--transition); font-size: 1.1rem; color: var(--text-muted); }
        .faq-item.active .faq-question .arrow { transform: rotate(180deg); color: var(--primary); }
        .faq-answer {
            max-height: 0; overflow: hidden;
            transition: max-height 0.4s ease, padding 0.4s ease;
            padding: 0 1.5rem; background: #fff;
        }
        .faq-item.active .faq-answer {
            max-height: 300px; padding: 1.2rem 1.5rem 1.5rem;
        }
        .faq-answer p { font-size: 0.95rem; color: var(--text-muted); line-height: 1.8; }

        /* ===== CTA ===== */
        .cta-section {
            background: linear-gradient(135deg, var(--primary) 0%, #1a7de6 100%);
            padding: 4.5rem 0; text-align: center;
        }
        .cta-section h2 { font-size: 2.2rem; font-weight: 800; color: #fff; margin-bottom: 0.8rem; }
        .cta-section p { font-size: 1.1rem; color: rgba(255,255,255,0.85); margin-bottom: 2rem; max-width: 600px; margin-left: auto; margin-right: auto; }
        .cta-section .btn-primary {
            background: #fff; color: var(--primary);
            box-shadow: 0 4px 16px rgba(0,0,0,0.15);
            font-size: 1.1rem; padding: 1rem 2.8rem;
        }
        .cta-section .btn-primary:hover { background: var(--accent); color: #fff; transform: translateY(-3px); box-shadow: 0 8px 24px rgba(0,0,0,0.25); }

        /* ===== Footer ===== */
        .site-footer {
            background: var(--bg-dark); color: rgba(255,255,255,0.7);
            padding: 4rem 0 0;
        }
        .footer-grid { display: grid; grid-template-columns: 1.5fr 1fr 1.5fr 1.5fr; gap: 2.5rem; margin-bottom: 2.5rem; }
        .footer-logo { font-size: 1.3rem; font-weight: 800; color: #fff !important; display: block; margin-bottom: 0.8rem; }
        .footer-grid p { font-size: 0.9rem; line-height: 1.7; margin-bottom: 0.6rem; }
        .footer-grid h4 { font-size: 1rem; font-weight: 700; color: #fff; margin-bottom: 1rem; }
        .footer-grid a { color: rgba(255,255,255,0.65); font-size: 0.9rem; display: block; margin-bottom: 0.5rem; }
        .footer-grid a:hover { color: var(--primary); }
        .footer-social { display: flex; gap: 0.8rem; margin-top: 1rem; }
        .footer-social a {
            width: 38px; height: 38px; border-radius: 50%;
            background: rgba(255,255,255,0.08); color: rgba(255,255,255,0.7);
            display: flex; align-items: center; justify-content: center;
            font-size: 1rem; transition: var(--transition);
        }
        .footer-social a:hover { background: var(--primary); color: #fff; transform: translateY(-2px); }
        .footer-bottom {
            border-top: 1px solid rgba(255,255,255,0.08);
            padding: 1.5rem 0; text-align: center;
            font-size: 0.85rem; color: rgba(255,255,255,0.5);
        }
        .footer-bottom a { color: var(--primary); font-weight: 500; display: inline; }
        .footer-bottom a:hover { color: var(--accent); }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .features-grid { grid-template-columns: repeat(2, 1fr); }
            .protection-grid { grid-template-columns: repeat(2, 1fr); }
            .stats-grid { grid-template-columns: repeat(2, 1fr); }
            .footer-grid { grid-template-columns: repeat(2, 1fr); }
        }
        @media (max-width: 768px) {
            .hamburger { display: block; }
            .nav-left, .nav-right {
                display: none; position: fixed; top: var(--header-height);
                left: 0; right: 0; background: rgba(255,255,255,0.98);
                backdrop-filter: blur(12px); flex-direction: column;
                padding: 1rem; gap: 0.25rem;
                box-shadow: 0 8px 24px rgba(0,0,0,0.1);
                transform: none;
            }
            .nav-left { top: var(--header-height); bottom: auto; }
            .nav-right { top: calc(var(--header-height) + 220px); bottom: auto; }
            .nav-open .nav-left, .nav-open .nav-right { display: flex; }
            .nav-open .nav-right { top: auto; bottom: auto; position: static; }
            .nav-open .site-header .container { flex-direction: column; align-items: flex-start; }
            .nav-open .nav-left, .nav-open .nav-right {
                position: static; transform: none; width: 100%;
                flex-direction: column; align-items: stretch;
                background: transparent; box-shadow: none; padding: 0.5rem 0;
            }
            .nav-link { padding: 0.7rem 1rem; border-radius: var(--radius-sm); }
            .nav-link.active::after { display: none; }
            .nav-link.active { background: var(--primary-light); }
            .nav-cta { text-align: center; }
            .hero-content h1 { font-size: 2.2rem; }
            .hero-content .subtitle { font-size: 1rem; }
            .features-grid { grid-template-columns: 1fr; }
            .arch-grid { grid-template-columns: 1fr; }
            .protection-grid { grid-template-columns: 1fr; }
            .stats-grid { grid-template-columns: repeat(2, 1fr); }
            .stat-item .num { font-size: 2rem; }
            .footer-grid { grid-template-columns: 1fr; gap: 1.5rem; }
            section { padding: 3rem 0; }
            .section-title h2 { font-size: 1.8rem; }
            .faq-question { font-size: 0.95rem; padding: 1rem 1.2rem; }
        }
        @media (max-width: 520px) {
            .hero-content h1 { font-size: 1.8rem; }
            .hero-actions { flex-direction: column; align-items: center; }
            .btn-primary, .btn-outline { width: 100%; justify-content: center; }
            .stats-grid { grid-template-columns: 1fr 1fr; gap: 1rem; }
            .stat-item .num { font-size: 1.8rem; }
            .footer-grid { grid-template-columns: 1fr; }
        }

        /* ===== Utility ===== */
        .badge-tag {
            display: inline-block; background: var(--accent-light);
            color: var(--accent); padding: 0.2rem 0.8rem;
            border-radius: 50px; font-size: 0.8rem; font-weight: 600;
        }
        .gap-1 { gap: 1rem; }
        .gap-2 { gap: 2rem; }
        .mb-3 { margin-bottom: 3rem; }

        /* ===== Floating animation ===== */
        @keyframes float { 0%, 100% { transform: translateY(0); } 50% { transform: translateY(-8px); } }
        .float-anim { animation: float 4s ease-in-out infinite; }
        .float-anim-delay { animation: float 5s ease-in-out 1s infinite; }

/* roulang page: category1 */
/* ===== Design Variables ===== */
        :root {
            --primary: #1E90FF;
            --primary-dark: #1a7fe6;
            --primary-light: #4da8ff;
            --secondary: #FF6B35;
            --secondary-dark: #e85d2c;
            --bg-light: #F8F9FA;
            --bg-dark: #1A1E2C;
            --bg-card: #ffffff;
            --text-dark: #222;
            --text-body: #333;
            --text-light: #666;
            --text-muted: #888;
            --border-color: #e8e8e8;
            --radius: 12px;
            --radius-sm: 8px;
            --shadow: 0 4px 12px rgba(0,0,0,0.06);
            --shadow-hover: 0 8px 24px rgba(0,0,0,0.12);
            --shadow-input: 0 0 0 3px rgba(30,144,255,0.2);
            --transition: all 0.3s ease;
            --font-sans: 'Segoe UI', 'PingFang SC', 'Microsoft YaHei', sans-serif;
            --container-max: 1200px;
            --header-h: 70px;
        }

        /* ===== Reset / Base ===== */
        *, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
        html { scroll-behavior: smooth; }
        body {
            font-family: var(--font-sans);
            font-size: 1rem;
            line-height: 1.7;
            color: var(--text-body);
            background: var(--bg-light);
            -webkit-font-smoothing: antialiased;
        }
        a { color: var(--primary); text-decoration: none; transition: var(--transition); }
        a:hover { color: var(--primary-dark); }
        img { max-width: 100%; height: auto; display: block; }
        ul, ol { list-style: none; }
        h1, h2, h3, h4, h5, h6 { font-weight: 700; line-height: 1.2; color: var(--text-dark); }
        input, button, textarea, select { font-family: inherit; font-size: inherit; outline: none; }
        button { cursor: pointer; border: none; background: none; }

        /* ===== Container ===== */
        .container {
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 24px;
        }

        /* ===== Header / Navigation ===== */
        .site-header {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: var(--header-h);
            background: #fff;
            box-shadow: 0 2px 12px rgba(0,0,0,0.06);
            z-index: 1000;
            display: flex;
            align-items: center;
        }
        .site-header .container {
            display: flex;
            align-items: center;
            justify-content: center;
            width: 100%;
            position: relative;
        }
        .nav-left, .nav-right {
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .nav-left { margin-right: auto; }
        .nav-right { margin-left: auto; }
        .nav-logo {
            font-size: 1.3rem;
            font-weight: 700;
            color: var(--primary);
            letter-spacing: 0.5px;
            white-space: nowrap;
            padding: 0 20px;
            transition: var(--transition);
        }
        .nav-logo:hover { color: var(--primary-dark); }
        .nav-link {
            font-size: 0.95rem;
            color: #555;
            padding: 8px 16px;
            border-radius: var(--radius-sm);
            transition: var(--transition);
            font-weight: 500;
        }
        .nav-link:hover { color: var(--primary); background: rgba(30,144,255,0.06); }
        .nav-link.active { color: var(--primary); background: rgba(30,144,255,0.10); font-weight: 600; }
        .nav-cta {
            background: var(--primary);
            color: #fff !important;
            padding: 8px 20px;
            border-radius: var(--radius-sm);
            font-weight: 600;
        }
        .nav-cta:hover { background: var(--primary-dark); color: #fff !important; transform: translateY(-1px); box-shadow: 0 4px 12px rgba(30,144,255,0.3); }

        .hamburger {
            display: none;
            font-size: 1.5rem;
            color: var(--primary);
            background: rgba(30,144,255,0.10);
            width: 44px;
            height: 44px;
            border-radius: 50%;
            align-items: center;
            justify-content: center;
            position: absolute;
            left: 16px;
            top: 50%;
            transform: translateY(-50%);
            z-index: 1100;
            transition: var(--transition);
        }
        .hamburger:hover { background: rgba(30,144,255,0.20); }

        /* Mobile Nav Overlay */
        .mobile-nav-overlay {
            display: none;
            position: fixed;
            top: 0; left: 0; width: 100%; height: 100%;
            background: rgba(0,0,0,0.5);
            z-index: 900;
            opacity: 0;
            transition: opacity 0.3s ease;
        }
        .mobile-nav-overlay.open { opacity: 1; }

        .mobile-nav-panel {
            position: fixed;
            top: 0; left: -280px;
            width: 280px;
            height: 100%;
            background: #fff;
            z-index: 950;
            box-shadow: 4px 0 20px rgba(0,0,0,0.10);
            padding: 24px 20px;
            display: flex;
            flex-direction: column;
            gap: 8px;
            transition: left 0.3s ease;
        }
        .mobile-nav-panel.open { left: 0; }
        .mobile-nav-panel .mnav-logo {
            font-size: 1.2rem;
            font-weight: 700;
            color: var(--primary);
            padding: 12px 0 20px 0;
            border-bottom: 1px solid var(--border-color);
            margin-bottom: 12px;
        }
        .mobile-nav-panel .mnav-link {
            font-size: 1rem;
            color: #444;
            padding: 12px 16px;
            border-radius: var(--radius-sm);
            transition: var(--transition);
            font-weight: 500;
        }
        .mobile-nav-panel .mnav-link:hover { background: rgba(30,144,255,0.06); color: var(--primary); }
        .mobile-nav-panel .mnav-link.active { color: var(--primary); background: rgba(30,144,255,0.10); font-weight: 600; }
        .mobile-nav-panel .mnav-cta {
            background: var(--primary);
            color: #fff;
            text-align: center;
            padding: 12px;
            border-radius: var(--radius-sm);
            font-weight: 600;
            margin-top: 12px;
        }
        .mobile-nav-panel .mnav-cta:hover { background: var(--primary-dark); color: #fff; }
        .mobile-nav-panel .close-btn {
            align-self: flex-end;
            font-size: 1.5rem;
            color: #888;
            padding: 4px 8px;
            transition: var(--transition);
        }
        .mobile-nav-panel .close-btn:hover { color: #333; }

        /* ===== Hero ===== */
        .hero-section {
            min-height: 100vh;
            display: flex;
            align-items: center;
            justify-content: center;
            text-align: center;
            position: relative;
            background: url('/assets/images/backpic/back-1.webp') center center / cover no-repeat;
            padding: 120px 24px 80px;
        }
        .hero-section::before {
            content: '';
            position: absolute;
            inset: 0;
            background: rgba(0,0,0,0.55);
        }
        .hero-content {
            position: relative;
            z-index: 2;
            max-width: 820px;
        }
        .hero-content h1 {
            font-size: 3rem;
            color: #fff;
            margin-bottom: 16px;
            letter-spacing: 1px;
            text-shadow: 0 2px 8px rgba(0,0,0,0.3);
        }
        .hero-content h1 span { color: var(--secondary); }
        .hero-content p {
            font-size: 1.2rem;
            color: rgba(255,255,255,0.85);
            margin-bottom: 32px;
            line-height: 1.8;
            max-width: 680px;
            margin-left: auto;
            margin-right: auto;
        }
        .hero-btns {
            display: flex;
            gap: 16px;
            justify-content: center;
            flex-wrap: wrap;
        }
        .btn-primary, .btn-outline {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 14px 32px;
            border-radius: var(--radius-sm);
            font-size: 1rem;
            font-weight: 600;
            transition: var(--transition);
            border: 2px solid transparent;
        }
        .btn-primary {
            background: var(--primary);
            color: #fff;
            border-color: var(--primary);
        }
        .btn-primary:hover { background: var(--primary-dark); border-color: var(--primary-dark); color: #fff; transform: translateY(-2px); box-shadow: 0 6px 20px rgba(30,144,255,0.35); }
        .btn-outline {
            background: transparent;
            color: #fff;
            border-color: rgba(255,255,255,0.7);
        }
        .btn-outline:hover { background: rgba(255,255,255,0.15); border-color: #fff; color: #fff; transform: translateY(-2px); }

        /* ===== Section通用 ===== */
        .section {
            padding: 80px 0;
        }
        .section-title {
            text-align: center;
            margin-bottom: 56px;
        }
        .section-title h2 {
            font-size: 2.25rem;
            margin-bottom: 12px;
        }
        .section-title p {
            font-size: 1.05rem;
            color: var(--text-light);
            max-width: 640px;
            margin: 0 auto;
        }
        .section-bg-alt { background: #fff; }
        .section-bg-dark {
            background: var(--bg-dark);
            color: rgba(255,255,255,0.85);
        }
        .section-bg-dark .section-title h2 { color: #fff; }
        .section-bg-dark .section-title p { color: rgba(255,255,255,0.7); }

        /* ===== Advantage Cards ===== */
        .advantage-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
        }
        .advantage-card {
            background: #fff;
            border-radius: var(--radius);
            padding: 32px 24px;
            box-shadow: var(--shadow);
            transition: var(--transition);
            text-align: center;
            border: 1px solid rgba(0,0,0,0.03);
        }
        .advantage-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-4px); }
        .advantage-card .icon {
            font-size: 2.2rem;
            color: var(--primary);
            margin-bottom: 16px;
            display: inline-block;
            width: 64px;
            height: 64px;
            line-height: 64px;
            border-radius: 50%;
            background: rgba(30,144,255,0.08);
        }
        .advantage-card h3 { font-size: 1.25rem; margin-bottom: 8px; }
        .advantage-card p { font-size: 0.95rem; color: var(--text-light); line-height: 1.6; }

        /* ===== Login Methods ===== */
        .methods-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
        }
        .method-card {
            background: #fff;
            border-radius: var(--radius);
            overflow: hidden;
            box-shadow: var(--shadow);
            transition: var(--transition);
            border: 1px solid rgba(0,0,0,0.03);
        }
        .method-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-4px); }
        .method-card .card-img {
            height: 200px;
            background: var(--bg-light) center center / cover no-repeat;
        }
        .method-card .card-body {
            padding: 24px;
        }
        .method-card .card-body h3 { font-size: 1.15rem; margin-bottom: 8px; }
        .method-card .card-body p { font-size: 0.95rem; color: var(--text-light); line-height: 1.6; }
        .method-card .badge {
            display: inline-block;
            background: rgba(30,144,255,0.10);
            color: var(--primary);
            font-size: 0.8rem;
            font-weight: 600;
            padding: 4px 12px;
            border-radius: 20px;
            margin-bottom: 12px;
        }

        /* ===== Steps ===== */
        .steps-grid {
            display: grid;
            grid-template-columns: repeat(5, 1fr);
            gap: 16px;
            counter-reset: step;
        }
        .step-item {
            background: rgba(255,255,255,0.06);
            border-radius: var(--radius);
            padding: 28px 16px;
            text-align: center;
            transition: var(--transition);
            border: 1px solid rgba(255,255,255,0.08);
            counter-increment: step;
        }
        .step-item:hover { background: rgba(255,255,255,0.10); transform: translateY(-4px); }
        .step-item .step-num {
            font-size: 2rem;
            font-weight: 700;
            color: var(--secondary);
            margin-bottom: 12px;
            display: block;
        }
        .step-item .step-num::before { content: "0" counter(step); }
        .step-item h4 { font-size: 1.05rem; color: #fff; margin-bottom: 6px; }
        .step-item p { font-size: 0.85rem; color: rgba(255,255,255,0.7); line-height: 1.5; }

        /* ===== Safety Tips ===== */
        .tips-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 20px;
        }
        .tip-card {
            background: #fff;
            border-radius: var(--radius);
            padding: 28px 20px;
            box-shadow: var(--shadow);
            transition: var(--transition);
            border-left: 4px solid var(--primary);
        }
        .tip-card:hover { box-shadow: var(--shadow-hover); transform: translateY(-3px); }
        .tip-card .tip-icon {
            font-size: 1.5rem;
            color: var(--primary);
            margin-bottom: 12px;
        }
        .tip-card h4 { font-size: 1.05rem; margin-bottom: 6px; }
        .tip-card p { font-size: 0.9rem; color: var(--text-light); line-height: 1.5; }

        /* ===== FAQ ===== */
        .faq-list {
            max-width: 800px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 12px;
        }
        .faq-item {
            background: #fff;
            border-radius: var(--radius-sm);
            box-shadow: 0 2px 8px rgba(0,0,0,0.04);
            border: 1px solid var(--border-color);
            overflow: hidden;
            transition: var(--transition);
        }
        .faq-item:hover { box-shadow: var(--shadow); }
        .faq-question {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 18px 24px;
            font-size: 1rem;
            font-weight: 600;
            color: var(--text-dark);
            cursor: pointer;
            transition: var(--transition);
            background: none;
            width: 100%;
            text-align: left;
        }
        .faq-question:hover { color: var(--primary); }
        .faq-question .faq-icon {
            transition: transform 0.3s ease;
            color: var(--text-muted);
            font-size: 1.1rem;
        }
        .faq-item.active .faq-question .faq-icon { transform: rotate(180deg); color: var(--primary); }
        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.4s ease, padding 0.3s ease;
            padding: 0 24px;
        }
        .faq-item.active .faq-answer {
            max-height: 300px;
            padding: 0 24px 20px 24px;
        }
        .faq-answer p { font-size: 0.95rem; color: var(--text-light); line-height: 1.7; }

        /* ===== CTA ===== */
        .cta-section {
            padding: 80px 0;
            text-align: center;
            background: linear-gradient(135deg, var(--primary) 0%, #0d6efd 100%);
            color: #fff;
        }
        .cta-section h2 {
            font-size: 2.25rem;
            color: #fff;
            margin-bottom: 12px;
        }
        .cta-section p {
            font-size: 1.1rem;
            color: rgba(255,255,255,0.85);
            margin-bottom: 32px;
            max-width: 600px;
            margin-left: auto;
            margin-right: auto;
        }
        .cta-section .btn-primary {
            background: #fff;
            color: var(--primary);
            border-color: #fff;
        }
        .cta-section .btn-primary:hover { background: rgba(255,255,255,0.9); color: var(--primary-dark); border-color: rgba(255,255,255,0.9); box-shadow: 0 6px 24px rgba(0,0,0,0.15); }

        /* ===== Footer ===== */
        .site-footer {
            background: var(--bg-dark);
            color: rgba(255,255,255,0.7);
            padding: 60px 0 0 0;
            font-size: 0.9rem;
        }
        .footer-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 32px;
            padding-bottom: 40px;
            border-bottom: 1px solid rgba(255,255,255,0.08);
        }
        .footer-grid h4 {
            color: #fff;
            font-size: 1.05rem;
            margin-bottom: 16px;
        }
        .footer-grid a {
            color: rgba(255,255,255,0.65);
            display: block;
            margin-bottom: 8px;
            transition: var(--transition);
        }
        .footer-grid a:hover { color: var(--primary-light); }
        .footer-grid p { line-height: 1.6; margin-bottom: 6px; }
        .footer-logo {
            font-size: 1.2rem;
            font-weight: 700;
            color: #fff !important;
            margin-bottom: 12px;
            display: inline-block;
        }
        .footer-social {
            display: flex;
            gap: 12px;
            margin-top: 16px;
        }
        .footer-social a {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            width: 40px;
            height: 40px;
            border-radius: 50%;
            background: rgba(255,255,255,0.08);
            color: rgba(255,255,255,0.7);
            font-size: 1.1rem;
            transition: var(--transition);
        }
        .footer-social a:hover { background: var(--primary); color: #fff; transform: translateY(-2px); }
        .footer-bottom {
            padding: 24px 0;
            text-align: center;
            font-size: 0.85rem;
            color: rgba(255,255,255,0.5);
            margin-top: 0;
        }
        .footer-bottom a { color: rgba(255,255,255,0.6); display: inline; margin: 0; }
        .footer-bottom a:hover { color: var(--primary-light); }

        /* ===== Responsive ===== */
        @media (max-width: 1024px) {
            .advantage-grid { grid-template-columns: repeat(2, 1fr); }
            .methods-grid { grid-template-columns: repeat(2, 1fr); }
            .steps-grid { grid-template-columns: repeat(3, 1fr); }
            .tips-grid { grid-template-columns: repeat(2, 1fr); }
            .footer-grid { grid-template-columns: repeat(2, 1fr); }
        }

        @media (max-width: 768px) {
            .site-header .container { justify-content: center; }
            .nav-left, .nav-right { display: none; }
            .hamburger { display: flex; }
            .hero-content h1 { font-size: 2rem; }
            .hero-content p { font-size: 1rem; }
            .section-title h2 { font-size: 1.75rem; }
            .advantage-grid { grid-template-columns: 1fr; }
            .methods-grid { grid-template-columns: 1fr; }
            .steps-grid { grid-template-columns: 1fr; }
            .tips-grid { grid-template-columns: 1fr; }
            .footer-grid { grid-template-columns: 1fr; }
            .section { padding: 48px 0; }
            .cta-section h2 { font-size: 1.75rem; }
            .site-footer { padding: 40px 0 0 0; }
            .hero-section { min-height: 80vh; padding: 100px 20px 60px; }
            .hero-btns { flex-direction: column; align-items: center; }
            .btn-primary, .btn-outline { width: 100%; max-width: 300px; justify-content: center; }
        }

        @media (max-width: 520px) {
            .hero-content h1 { font-size: 1.6rem; }
            .hero-content p { font-size: 0.9rem; }
            .section-title h2 { font-size: 1.4rem; }
            .nav-logo { font-size: 1rem; padding: 0 12px; }
            .footer-grid { gap: 24px; }
            .method-card .card-img { height: 160px; }
        }

        /* ===== Smooth scroll offset ===== */
        .scroll-offset { scroll-margin-top: 80px; }