/* roulang page: index */
:root {
            --color-primary: #0F766E;
            --color-primary-dark: #0B5D56;
            --color-primary-light: #14B8A6;
            --color-accent: #F97316;
            --color-accent-dark: #EA580C;
            --color-bg: #F8FAFC;
            --color-surface: #FFFFFF;
            --color-text: #1E293B;
            --color-text-secondary: #475569;
            --color-text-muted: #94A3B8;
            --color-border: #E2E8F0;
            --color-border-strong: #CBD5E1;
            --radius-sm: 8px;
            --radius-md: 16px;
            --radius-lg: 24px;
            --radius-full: 9999px;
            --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.06);
            --shadow-md: 0 8px 24px rgba(15, 23, 42, 0.08);
            --shadow-lg: 0 16px 48px rgba(15, 23, 42, 0.12);
            --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', 'Noto Sans SC', system-ui, -apple-system, sans-serif;
            --transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
            --max-width: 1200px;
            --section-padding: 80px 0;
        }

        *,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        html {
            scroll-behavior: smooth;
            -webkit-text-size-adjust: 100%;
            -webkit-tap-highlight-color: transparent;
        }

        body {
            font-family: var(--font-sans);
            font-size: 16px;
            line-height: 1.7;
            color: var(--color-text);
            background-color: var(--color-bg);
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            overflow-x: hidden;
        }

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

        a {
            color: inherit;
            text-decoration: none;
            transition: var(--transition);
        }

        a:hover {
            color: var(--color-primary);
        }

        button,
        input,
        textarea,
        select {
            font-family: inherit;
            font-size: inherit;
            line-height: inherit;
            border: none;
            outline: none;
            background: none;
        }

        button {
            cursor: pointer;
        }

        button:focus-visible,
        a:focus-visible,
        input:focus-visible,
        textarea:focus-visible {
            outline: 3px solid rgba(15, 118, 110, 0.4);
            outline-offset: 2px;
            border-radius: 4px;
        }

        ul,
        ol {
            list-style: none;
        }

        .container {
            width: 100%;
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 24px;
        }

        /* ============ Header / Nav ============ */
        .site-header {
            background: rgba(255, 255, 255, 0.92);
            backdrop-filter: blur(12px);
            -webkit-backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--color-border);
            position: sticky;
            top: 0;
            z-index: 100;
            transition: box-shadow 0.3s ease;
        }

        .site-header.scrolled {
            box-shadow: 0 4px 20px rgba(15, 23, 42, 0.08);
        }

        .nav-wrapper {
            display: flex;
            align-items: center;
            justify-content: space-between;
            min-height: 72px;
            gap: 16px;
        }

        .nav-logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 1.35rem;
            font-weight: 800;
            letter-spacing: -0.01em;
            color: var(--color-text);
            flex-shrink: 0;
        }

        .nav-logo:hover {
            color: var(--color-primary);
        }

        .nav-logo .logo-icon {
            width: 38px;
            height: 38px;
            background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-light) 100%);
            border-radius: 10px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: #fff;
            font-weight: 800;
            font-size: 1rem;
            flex-shrink: 0;
            box-shadow: 0 4px 12px rgba(15, 118, 110, 0.3);
        }

        .nav-links {
            display: flex;
            align-items: center;
            gap: 32px;
        }

        .nav-links a {
            font-size: 0.95rem;
            font-weight: 500;
            color: var(--color-text-secondary);
            position: relative;
            padding: 6px 0;
            white-space: nowrap;
        }

        .nav-links a::after {
            content: '';
            position: absolute;
            left: 0;
            bottom: -2px;
            width: 0;
            height: 2px;
            background: var(--color-primary);
            border-radius: 2px;
            transition: width 0.25s ease;
        }

        .nav-links a:hover::after,
        .nav-links a.active::after {
            width: 100%;
        }

        .nav-links a.active {
            color: var(--color-primary);
            font-weight: 600;
        }

        .nav-actions {
            display: flex;
            align-items: center;
            gap: 12px;
            flex-shrink: 0;
        }

        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 10px 22px;
            border-radius: var(--radius-full);
            font-weight: 600;
            font-size: 0.925rem;
            transition: var(--transition);
            white-space: nowrap;
            gap: 8px;
        }

        .btn-primary {
            background: var(--color-primary);
            color: #fff;
            box-shadow: 0 4px 14px rgba(15, 118, 110, 0.3);
        }

        .btn-primary:hover {
            background: var(--color-primary-dark);
            box-shadow: 0 6px 20px rgba(15, 118, 110, 0.4);
            transform: translateY(-2px);
            color: #fff;
        }

        .btn-primary:active {
            transform: translateY(0);
            box-shadow: 0 2px 8px rgba(15, 118, 110, 0.3);
        }

        .btn-outline {
            background: transparent;
            color: var(--color-text);
            border: 2px solid var(--color-border-strong);
        }

        .btn-outline:hover {
            border-color: var(--color-primary);
            color: var(--color-primary);
            background: rgba(15, 118, 110, 0.05);
        }

        .btn-accent {
            background: var(--color-accent);
            color: #fff;
            box-shadow: 0 4px 14px rgba(249, 115, 22, 0.3);
        }

        .btn-accent:hover {
            background: var(--color-accent-dark);
            box-shadow: 0 6px 20px rgba(249, 115, 22, 0.4);
            transform: translateY(-2px);
            color: #fff;
        }

        .btn-lg {
            padding: 14px 32px;
            font-size: 1rem;
        }

        .btn-sm {
            padding: 8px 16px;
            font-size: 0.85rem;
        }

        .mobile-toggle {
            display: none;
            flex-direction: column;
            gap: 5px;
            padding: 8px;
            background: none;
            border: none;
            cursor: pointer;
        }

        .mobile-toggle span {
            display: block;
            width: 26px;
            height: 3px;
            border-radius: 3px;
            background: var(--color-text);
            transition: var(--transition);
        }

        .mobile-toggle.active span:nth-child(1) {
            transform: translateY(8px) rotate(45deg);
        }

        .mobile-toggle.active span:nth-child(2) {
            opacity: 0;
        }

        .mobile-toggle.active span:nth-child(3) {
            transform: translateY(-8px) rotate(-45deg);
        }

        .mobile-menu {
            display: none;
            background: #fff;
            border-top: 1px solid var(--color-border);
            padding: 16px 24px 24px;
            flex-direction: column;
            gap: 12px;
        }

        .mobile-menu.open {
            display: flex;
        }

        .mobile-menu a {
            font-size: 1rem;
            font-weight: 500;
            color: var(--color-text-secondary);
            padding: 8px 0;
            border-bottom: 1px solid var(--color-border);
        }

        .mobile-menu a:last-child {
            border-bottom: none;
        }

        /* ============ Hero ============ */
        .hero {
            padding: 72px 0 64px;
            background: linear-gradient(180deg, #F0FDF9 0%, var(--color-bg) 100%);
            position: relative;
            overflow: hidden;
        }

        .hero::before {
            content: '';
            position: absolute;
            top: -180px;
            right: -120px;
            width: 550px;
            height: 550px;
            border-radius: 50%;
            background: radial-gradient(circle, rgba(20, 184, 166, 0.12) 0%, rgba(20, 184, 166, 0) 70%);
            pointer-events: none;
        }

        .hero::after {
            content: '';
            position: absolute;
            bottom: -150px;
            left: -100px;
            width: 480px;
            height: 480px;
            border-radius: 50%;
            background: radial-gradient(circle, rgba(249, 115, 22, 0.08) 0%, rgba(249, 115, 22, 0) 70%);
            pointer-events: none;
        }

        .hero .container {
            position: relative;
            z-index: 1;
            text-align: center;
            max-width: 860px;
        }

        .hero-tag {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            background: #fff;
            border: 1px solid var(--color-border);
            border-radius: var(--radius-full);
            padding: 8px 18px;
            font-size: 0.85rem;
            font-weight: 500;
            color: var(--color-primary);
            box-shadow: var(--shadow-sm);
            margin-bottom: 24px;
            transition: var(--transition);
        }

        .hero-tag:hover {
            box-shadow: var(--shadow-md);
            transform: translateY(-2px);
        }

        .hero-tag .dot {
            width: 8px;
            height: 8px;
            border-radius: 50%;
            background: var(--color-primary-light);
            animation: pulse-dot 2s ease-in-out infinite;
        }

        @keyframes pulse-dot {
            0%, 100% {
                opacity: 1;
                transform: scale(1);
            }
            50% {
                opacity: 0.5;
                transform: scale(1.4);
            }
        }

        .hero h1 {
            font-size: 2.75rem;
            font-weight: 800;
            line-height: 1.25;
            letter-spacing: -0.02em;
            margin-bottom: 20px;
            color: var(--color-text);
        }

        .hero h1 .highlight {
            color: var(--color-primary);
            position: relative;
            white-space: nowrap;
        }

        .hero h1 .highlight::after {
            content: '';
            position: absolute;
            left: 0;
            bottom: -2px;
            width: 100%;
            height: 6px;
            background: rgba(20, 184, 166, 0.25);
            border-radius: 3px;
        }

        .hero-sub {
            font-size: 1.15rem;
            color: var(--color-text-secondary);
            line-height: 1.8;
            max-width: 680px;
            margin: 0 auto 36px;
            font-weight: 400;
        }

        .hero-search {
            display: flex;
            align-items: center;
            max-width: 560px;
            margin: 0 auto 28px;
            background: #fff;
            border: 2px solid var(--color-border);
            border-radius: var(--radius-full);
            padding: 6px 6px 6px 20px;
            transition: var(--transition);
            box-shadow: var(--shadow-sm);
        }

        .hero-search:focus-within {
            border-color: var(--color-primary);
            box-shadow: 0 8px 28px rgba(15, 118, 110, 0.15);
        }

        .hero-search input {
            flex: 1;
            padding: 10px 12px 10px 0;
            font-size: 0.95rem;
            color: var(--color-text);
        }

        .hero-search input::placeholder {
            color: var(--color-text-muted);
        }

        .hero-search .btn {
            flex-shrink: 0;
        }

        .hero-tags {
            display: flex;
            align-items: center;
            justify-content: center;
            flex-wrap: wrap;
            gap: 10px;
        }

        .hero-tags span.label {
            font-size: 0.85rem;
            color: var(--color-text-muted);
            font-weight: 500;
        }

        .hero-tags .tag-chip {
            display: inline-block;
            padding: 6px 16px;
            border-radius: var(--radius-full);
            background: #fff;
            border: 1px solid var(--color-border);
            font-size: 0.82rem;
            color: var(--color-text-secondary);
            transition: var(--transition);
            cursor: pointer;
            font-weight: 500;
        }

        .hero-tags .tag-chip:hover {
            border-color: var(--color-primary);
            color: var(--color-primary);
            box-shadow: var(--shadow-sm);
            transform: translateY(-1px);
        }

        .hero-stats {
            display: flex;
            align-items: center;
            justify-content: center;
            flex-wrap: wrap;
            gap: 40px;
            margin-top: 44px;
            padding-top: 32px;
            border-top: 1px solid var(--color-border);
        }

        .hero-stat {
            text-align: center;
        }

        .hero-stat .number {
            font-size: 1.8rem;
            font-weight: 800;
            color: var(--color-primary);
            letter-spacing: -0.01em;
        }

        .hero-stat .label {
            font-size: 0.82rem;
            color: var(--color-text-muted);
            margin-top: 2px;
        }

        /* ============ Section 通用 ============ */
        section {
            padding: var(--section-padding);
        }

        .section-head {
            text-align: center;
            max-width: 640px;
            margin: 0 auto 48px;
        }

        .section-head .section-tag {
            display: inline-block;
            padding: 6px 16px;
            background: rgba(15, 118, 110, 0.08);
            color: var(--color-primary);
            border-radius: var(--radius-full);
            font-size: 0.82rem;
            font-weight: 600;
            letter-spacing: 0.03em;
            margin-bottom: 14px;
        }

        .section-head h2 {
            font-size: 2rem;
            font-weight: 800;
            letter-spacing: -0.015em;
            line-height: 1.3;
            color: var(--color-text);
            margin-bottom: 12px;
        }

        .section-head p {
            font-size: 1rem;
            color: var(--color-text-secondary);
            line-height: 1.75;
        }

        /* ============ Features Section ============ */
        .features {
            background: var(--color-surface);
        }

        .features-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
        }

        .feature-card {
            background: var(--color-bg);
            border: 1px solid var(--color-border);
            border-radius: var(--radius-md);
            padding: 28px 24px;
            transition: var(--transition);
            position: relative;
            overflow: hidden;
        }

        .feature-card::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            height: 4px;
            background: var(--color-primary);
            opacity: 0;
            transition: opacity 0.3s ease;
        }

        .feature-card:hover {
            transform: translateY(-6px);
            box-shadow: var(--shadow-md);
            border-color: var(--color-primary-light);
        }

        .feature-card:hover::before {
            opacity: 1;
        }

        .feature-icon {
            width: 48px;
            height: 48px;
            border-radius: 12px;
            background: rgba(15, 118, 110, 0.1);
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 18px;
            font-size: 1.4rem;
            transition: var(--transition);
        }

        .feature-card:hover .feature-icon {
            background: var(--color-primary);
            transform: scale(1.05);
        }

        .feature-card h3 {
            font-size: 1.1rem;
            font-weight: 700;
            margin-bottom: 10px;
            color: var(--color-text);
        }

        .feature-card p {
            font-size: 0.9rem;
            color: var(--color-text-secondary);
            line-height: 1.7;
        }

        .feature-card.accent .feature-icon {
            background: rgba(249, 115, 22, 0.1);
        }

        .feature-card.accent:hover .feature-icon {
            background: var(--color-accent);
        }

        /* ============ Latest Section ============ */
        .latest {
            background: var(--color-bg);
        }

        .latest-list {
            display: grid;
            grid-template-columns: 1fr;
            gap: 16px;
            max-width: 800px;
            margin: 0 auto;
        }

        .latest-item {
            display: flex;
            align-items: flex-start;
            gap: 18px;
            background: var(--color-surface);
            border: 1px solid var(--color-border);
            border-radius: var(--radius-md);
            padding: 22px 24px;
            transition: var(--transition);
            cursor: pointer;
        }

        .latest-item:hover {
            border-color: var(--color-primary-light);
            box-shadow: var(--shadow-md);
            transform: translateX(4px);
        }

        .latest-index {
            font-size: 1.6rem;
            font-weight: 800;
            color: var(--color-border-strong);
            min-width: 48px;
            line-height: 1.3;
            transition: var(--transition);
            flex-shrink: 0;
        }

        .latest-item:hover .latest-index {
            color: var(--color-primary);
        }

        .latest-content {
            flex: 1;
            min-width: 0;
        }

        .latest-meta {
            display: flex;
            align-items: center;
            flex-wrap: wrap;
            gap: 10px;
            margin-bottom: 8px;
        }

        .latest-badge {
            display: inline-block;
            padding: 3px 10px;
            border-radius: var(--radius-full);
            font-size: 0.72rem;
            font-weight: 600;
            letter-spacing: 0.02em;
            background: rgba(15, 118, 110, 0.1);
            color: var(--color-primary);
        }

        .latest-badge.hot {
            background: rgba(249, 115, 22, 0.12);
            color: var(--color-accent);
        }

        .latest-badge.new {
            background: rgba(59, 130, 246, 0.1);
            color: #3B82F6;
        }

        .latest-date {
            font-size: 0.8rem;
            color: var(--color-text-muted);
        }

        .latest-content h3 {
            font-size: 1.05rem;
            font-weight: 700;
            color: var(--color-text);
            margin-bottom: 6px;
            transition: var(--transition);
        }

        .latest-item:hover .latest-content h3 {
            color: var(--color-primary);
        }

        .latest-content p {
            font-size: 0.88rem;
            color: var(--color-text-secondary);
            line-height: 1.65;
        }

        .latest-arrow {
            align-self: center;
            flex-shrink: 0;
            width: 36px;
            height: 36px;
            border-radius: 50%;
            background: var(--color-bg);
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--color-text-muted);
            font-weight: 700;
            transition: var(--transition);
        }

        .latest-item:hover .latest-arrow {
            background: var(--color-primary);
            color: #fff;
            transform: translateX(4px);
        }

        /* ============ Topics Section ============ */
        .topics {
            background: var(--color-surface);
        }

        .topics-wrapper {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 20px;
        }

        .topic-card {
            background: var(--color-bg);
            border: 1px solid var(--color-border);
            border-radius: var(--radius-md);
            padding: 28px 24px;
            transition: var(--transition);
            text-align: center;
        }

        .topic-card:hover {
            border-color: var(--color-primary-light);
            box-shadow: var(--shadow-md);
            transform: translateY(-4px);
        }

        .topic-card .topic-num {
            font-size: 2.2rem;
            font-weight: 800;
            color: var(--color-primary);
            opacity: 0.25;
            line-height: 1;
            margin-bottom: 10px;
        }

        .topic-card h3 {
            font-size: 1.05rem;
            font-weight: 700;
            color: var(--color-text);
            margin-bottom: 8px;
        }

        .topic-card p {
            font-size: 0.88rem;
            color: var(--color-text-secondary);
            line-height: 1.65;
        }

        .topic-tags {
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
            gap: 10px;
            margin-top: 32px;
            padding-top: 26px;
            border-top: 1px solid var(--color-border);
        }

        .topic-tag {
            display: inline-block;
            padding: 8px 18px;
            border-radius: var(--radius-full);
            background: #fff;
            border: 1px solid var(--color-border);
            font-size: 0.85rem;
            color: var(--color-text-secondary);
            transition: var(--transition);
            cursor: pointer;
            font-weight: 500;
        }

        .topic-tag:hover {
            border-color: var(--color-primary);
            color: var(--color-primary);
            box-shadow: var(--shadow-sm);
            transform: translateY(-2px);
        }

        /* ============ FAQ Section ============ */
        .faq {
            background: var(--color-bg);
        }

        .faq-list {
            max-width: 760px;
            margin: 0 auto;
            display: flex;
            flex-direction: column;
            gap: 14px;
        }

        .faq-item {
            background: var(--color-surface);
            border: 1px solid var(--color-border);
            border-radius: var(--radius-md);
            overflow: hidden;
            transition: var(--transition);
        }

        .faq-item:hover {
            border-color: var(--color-border-strong);
        }

        .faq-item.open {
            border-color: var(--color-primary);
            box-shadow: var(--shadow-md);
        }

        .faq-question {
            display: flex;
            align-items: center;
            justify-content: space-between;
            gap: 16px;
            padding: 20px 24px;
            cursor: pointer;
            background: none;
            width: 100%;
            text-align: left;
            font-weight: 600;
            font-size: 0.98rem;
            color: var(--color-text);
            transition: var(--transition);
        }

        .faq-question:hover {
            color: var(--color-primary);
        }

        .faq-question .faq-icon {
            flex-shrink: 0;
            width: 28px;
            height: 28px;
            border-radius: 50%;
            background: var(--color-bg);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 1.1rem;
            transition: var(--transition);
            color: var(--color-text-muted);
            font-weight: 700;
        }

        .faq-item.open .faq-question .faq-icon {
            background: var(--color-primary);
            color: #fff;
            transform: rotate(45deg);
        }

        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease, padding 0.35s ease;
            padding: 0 24px;
        }

        .faq-item.open .faq-answer {
            max-height: 300px;
            padding: 0 24px 20px;
        }

        .faq-answer p {
            font-size: 0.9rem;
            color: var(--color-text-secondary);
            line-height: 1.7;
        }

        /* ============ CTA Section ============ */
        .cta-section {
            background: var(--color-surface);
            padding: 60px 0;
        }

        .cta-box {
            background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
            border-radius: var(--radius-lg);
            padding: 56px 48px;
            text-align: center;
            color: #fff;
            position: relative;
            overflow: hidden;
        }

        .cta-box::before {
            content: '';
            position: absolute;
            top: -60%;
            right: -20%;
            width: 400px;
            height: 400px;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.06);
            pointer-events: none;
        }

        .cta-box::after {
            content: '';
            position: absolute;
            bottom: -50%;
            left: -15%;
            width: 350px;
            height: 350px;
            border-radius: 50%;
            background: rgba(255, 255, 255, 0.04);
            pointer-events: none;
        }

        .cta-box h2 {
            font-size: 1.9rem;
            font-weight: 800;
            letter-spacing: -0.015em;
            margin-bottom: 14px;
            position: relative;
            z-index: 1;
        }

        .cta-box p {
            font-size: 1rem;
            color: rgba(255, 255, 255, 0.85);
            max-width: 540px;
            margin: 0 auto 28px;
            line-height: 1.7;
            position: relative;
            z-index: 1;
        }

        .cta-box .btn {
            position: relative;
            z-index: 1;
            background: #fff;
            color: var(--color-primary);
            box-shadow: 0 8px 24px rgba(0, 0, 0, 0.2);
        }

        .cta-box .btn:hover {
            transform: translateY(-3px);
            box-shadow: 0 12px 32px rgba(0, 0, 0, 0.3);
            color: var(--color-primary-dark);
        }

        .cta-box .cta-note {
            margin-top: 16px;
            font-size: 0.82rem;
            color: rgba(255, 255, 255, 0.6);
            position: relative;
            z-index: 1;
        }

        /* ============ Footer ============ */
        .site-footer {
            background: #0F172A;
            color: #CBD5E1;
            padding: 56px 0 28px;
            margin-top: auto;
        }

        .footer-grid {
            display: grid;
            grid-template-columns: 2fr 1fr 1fr;
            gap: 40px;
            margin-bottom: 36px;
        }

        .footer-brand .footer-logo {
            display: flex;
            align-items: center;
            gap: 10px;
            font-size: 1.2rem;
            font-weight: 800;
            color: #fff;
            margin-bottom: 14px;
        }

        .footer-brand .footer-logo .logo-icon {
            width: 32px;
            height: 32px;
            border-radius: 8px;
            background: var(--color-primary);
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 0.85rem;
            color: #fff;
        }

        .footer-brand p {
            font-size: 0.88rem;
            color: #94A3B8;
            line-height: 1.7;
            max-width: 340px;
        }

        .footer-col h4 {
            font-size: 0.92rem;
            font-weight: 700;
            color: #fff;
            margin-bottom: 16px;
            letter-spacing: 0.02em;
        }

        .footer-col ul {
            display: flex;
            flex-direction: column;
            gap: 10px;
        }

        .footer-col ul a {
            font-size: 0.88rem;
            color: #94A3B8;
            transition: var(--transition);
        }

        .footer-col ul a:hover {
            color: #fff;
            padding-left: 4px;
        }

        .footer-bottom {
            border-top: 1px solid rgba(148, 163, 184, 0.15);
            padding-top: 22px;
            display: flex;
            align-items: center;
            justify-content: space-between;
            flex-wrap: wrap;
            gap: 12px;
            font-size: 0.82rem;
            color: #64748B;
        }

        .footer-bottom a {
            color: #94A3B8;
            transition: var(--transition);
        }

        .footer-bottom a:hover {
            color: #fff;
        }

        /* ============ 响应式 ============ */
        @media screen and (max-width: 1024px) {
            .features-grid {
                grid-template-columns: repeat(2, 1fr);
            }

            .topics-wrapper {
                grid-template-columns: repeat(2, 1fr);
            }

            .footer-grid {
                grid-template-columns: 1fr 1fr;
            }

            .hero h1 {
                font-size: 2.2rem;
            }
        }

        @media screen and (max-width: 768px) {
            :root {
                --section-padding: 56px 0;
            }

            .nav-links {
                display: none;
            }

            .nav-actions .btn-outline {
                display: none;
            }

            .mobile-toggle {
                display: flex;
            }

            .hero {
                padding: 48px 0 40px;
            }

            .hero h1 {
                font-size: 1.8rem;
                line-height: 1.35;
            }

            .hero-sub {
                font-size: 1rem;
                margin-bottom: 24px;
            }

            .hero-stats {
                gap: 24px;
                margin-top: 32px;
                padding-top: 24px;
            }

            .hero-stat .number {
                font-size: 1.4rem;
            }

            .section-head h2 {
                font-size: 1.6rem;
            }

            .features-grid {
                grid-template-columns: 1fr;
                gap: 16px;
            }

            .topics-wrapper {
                grid-template-columns: 1fr;
                gap: 16px;
            }

            .latest-item {
                align-items: flex-start;
                padding: 18px 16px;
                gap: 12px;
            }

            .latest-index {
                font-size: 1.2rem;
                min-width: 32px;
            }

            .latest-content h3 {
                font-size: 0.95rem;
            }

            .cta-box {
                padding: 36px 24px;
                border-radius: var(--radius-md);
            }

            .cta-box h2 {
                font-size: 1.5rem;
            }

            .footer-grid {
                grid-template-columns: 1fr;
                gap: 28px;
            }

            .hero-search {
                flex-direction: row;
                flex-wrap: nowrap;
                padding: 4px 4px 4px 16px;
            }

            .hero-search input {
                font-size: 0.85rem;
                padding: 8px 8px 8px 0;
            }

            .hero-search .btn {
                padding: 8px 16px;
                font-size: 0.82rem;
            }
        }

        @media screen and (max-width: 520px) {
            .container {
                padding: 0 16px;
            }

            .hero h1 {
                font-size: 1.5rem;
            }

            .hero h1 .highlight {
                white-space: normal;
            }

            .hero-sub {
                font-size: 0.92rem;
            }

            .hero-tags {
                gap: 6px;
            }

            .hero-tags .tag-chip {
                font-size: 0.75rem;
                padding: 5px 12px;
            }

            .hero-stats {
                flex-direction: row;
                flex-wrap: wrap;
                gap: 16px;
                justify-content: center;
            }

            .hero-stat .number {
                font-size: 1.2rem;
            }

            .hero-stat .label {
                font-size: 0.72rem;
            }

            .section-head h2 {
                font-size: 1.4rem;
            }

            .section-head {
                margin-bottom: 32px;
            }

            .nav-logo {
                font-size: 1.1rem;
            }

            .nav-logo .logo-icon {
                width: 30px;
                height: 30px;
                font-size: 0.8rem;
                border-radius: 8px;
            }

            .btn-lg {
                padding: 12px 24px;
                font-size: 0.9rem;
            }

            .cta-box h2 {
                font-size: 1.3rem;
            }

            .cta-box p {
                font-size: 0.88rem;
            }

            .faq-question {
                font-size: 0.88rem;
                padding: 16px 18px;
            }

            .faq-answer {
                padding: 0 18px;
            }

            .faq-item.open .faq-answer {
                padding: 0 18px 16px;
            }

            .footer-bottom {
                flex-direction: column;
                text-align: center;
                justify-content: center;
            }
        }