/* roulang page: index */
:root {
            --color-primary: #4A3728;
            --color-primary-dark: #3A2A1C;
            --color-secondary: #5A6B4D;
            --color-bg-primary: #FAF7F2;
            --color-bg-secondary: #F3EFE8;
            --color-text-primary: #2C241E;
            --color-text-secondary: #7A7068;
            --color-accent: #B8863F;
            --color-accent-light: #C9A050;
            --color-border: #E5DFD8;
            --color-white: #FFFFFF;
            --font-cn: "PingFang SC", "Noto Sans SC", "Microsoft YaHei", "Hiragino Sans GB", sans-serif;
            --font-mono: "SF Mono", "Consolas", "Monaco", "Menlo", monospace;
            --container-max: 1200px;
            --card-radius: 12px;
            --btn-radius: 8px;
            --transition-fast: 0.25s ease-out;
            --transition-smooth: 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
            --shadow-card: 0 1px 3px rgba(44, 36, 30, 0.06), 0 1px 2px rgba(44, 36, 30, 0.04);
            --shadow-card-hover: 0 8px 24px rgba(44, 36, 30, 0.10), 0 2px 6px rgba(44, 36, 30, 0.06);
            --shadow-nav: 0 1px 6px rgba(44, 36, 30, 0.08);
        }

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

        html {
            scroll-behavior: smooth;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        body {
            font-family: var(--font-cn);
            font-size: 16px;
            font-weight: 400;
            line-height: 1.7;
            color: var(--color-text-primary);
            background-color: var(--color-bg-primary);
            overflow-x: hidden;
        }

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

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

        button {
            cursor: pointer;
            border: none;
            font-family: inherit;
        }

        .container {
            max-width: var(--container-max);
            margin: 0 auto;
            padding-left: 32px;
            padding-right: 32px;
        }

        @media (max-width: 768px) {
            .container {
                padding-left: 16px;
                padding-right: 16px;
            }
        }

        /* Navigation */
        .site-nav {
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            z-index: 1000;
            height: 64px;
            background-color: rgba(250, 247, 242, 0.98);
            transition: box-shadow var(--transition-smooth), background-color var(--transition-smooth);
            display: flex;
            align-items: center;
        }

        .site-nav.scrolled {
            box-shadow: var(--shadow-nav);
            background-color: rgba(255, 255, 255, 1);
        }

        .nav-inner {
            display: flex;
            align-items: center;
            justify-content: space-between;
            width: 100%;
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 32px;
        }

        .nav-logo {
            font-size: 20px;
            font-weight: 700;
            color: var(--color-primary);
            letter-spacing: 0.02em;
            display: flex;
            align-items: center;
            gap: 8px;
            flex-shrink: 0;
            z-index: 1001;
        }

        .nav-logo-icon {
            width: 24px;
            height: 24px;
            display: flex;
            align-items: center;
            justify-content: center;
            flex-shrink: 0;
        }

        .nav-logo-icon svg {
            width: 100%;
            height: 100%;
        }

        .nav-links {
            display: flex;
            align-items: center;
            gap: 32px;
            list-style: none;
        }

        .nav-links a {
            font-size: 14px;
            font-weight: 500;
            color: var(--color-text-secondary);
            position: relative;
            padding-bottom: 4px;
            transition: color var(--transition-fast);
        }

        .nav-links a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%) scaleX(0);
            width: 100%;
            height: 1.5px;
            background-color: var(--color-primary);
            border-radius: 1px;
            transition: transform var(--transition-smooth);
            transform-origin: center;
        }

        .nav-links a:hover,
        .nav-links a.active {
            color: var(--color-primary);
        }

        .nav-links a:hover::after,
        .nav-links a.active::after {
            transform: translateX(-50%) scaleX(1);
        }

        /* Hamburger */
        .hamburger {
            display: none;
            flex-direction: column;
            gap: 6px;
            cursor: pointer;
            z-index: 1001;
            padding: 8px;
            background: none;
            border: none;
        }

        .hamburger span {
            display: block;
            width: 26px;
            height: 2px;
            background-color: var(--color-primary);
            border-radius: 2px;
            transition: all var(--transition-smooth);
            transform-origin: center;
        }

        .hamburger.active span:nth-child(1) {
            transform: translateY(8px) rotate(45deg);
        }
        .hamburger.active span:nth-child(2) {
            opacity: 0;
            transform: scaleX(0);
        }
        .hamburger.active span:nth-child(3) {
            transform: translateY(-8px) rotate(-45deg);
        }

        .mobile-menu {
            display: none;
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background-color: rgba(250, 247, 242, 0.99);
            z-index: 999;
            flex-direction: column;
            align-items: center;
            justify-content: center;
            gap: 28px;
            opacity: 0;
            pointer-events: none;
            transition: opacity var(--transition-smooth);
        }

        .mobile-menu.open {
            opacity: 1;
            pointer-events: auto;
        }

        .mobile-menu a {
            font-size: 20px;
            font-weight: 600;
            color: var(--color-text-primary);
            transition: color var(--transition-fast);
        }
        .mobile-menu a:hover {
            color: var(--color-primary);
        }

        @media (max-width: 768px) {
            .nav-links {
                display: none;
            }
            .hamburger {
                display: flex;
            }
            .mobile-menu {
                display: flex;
            }
            .nav-inner {
                padding: 0 16px;
            }
            .site-nav {
                height: 56px;
            }
        }

        /* Hero */
        #hero {
            min-height: 100vh;
            display: flex;
            align-items: center;
            background-color: var(--color-bg-primary);
            position: relative;
            overflow: hidden;
            padding-top: 64px;
        }

        @media (max-width: 768px) {
            #hero {
                padding-top: 56px;
                min-height: auto;
                padding-bottom: 48px;
            }
        }

        .hero-bg-texture {
            position: absolute;
            inset: 0;
            pointer-events: none;
            opacity: 0.04;
            background-image:
                linear-gradient(var(--color-primary) 0.5px, transparent 0.5px),
                linear-gradient(90deg, var(--color-primary) 0.5px, transparent 0.5px);
            background-size: 48px 48px;
            z-index: 0;
        }

        .hero-inner {
            display: flex;
            align-items: center;
            gap: 60px;
            width: 100%;
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 32px;
            position: relative;
            z-index: 1;
        }

        @media (max-width: 1024px) {
            .hero-inner {
                gap: 36px;
            }
        }

        @media (max-width: 768px) {
            .hero-inner {
                flex-direction: column;
                gap: 40px;
                padding: 0 16px;
                text-align: center;
            }
        }

        .hero-text {
            flex: 0 0 48%;
            max-width: 48%;
        }

        @media (max-width: 768px) {
            .hero-text {
                flex: 1 1 auto;
                max-width: 100%;
                order: 2;
            }
        }

        .hero-visual {
            flex: 0 0 48%;
            max-width: 48%;
            position: relative;
        }

        @media (max-width: 768px) {
            .hero-visual {
                flex: 1 1 auto;
                max-width: 100%;
                order: 1;
                max-height: 280px;
                overflow: hidden;
                border-radius: 12px;
            }
        }

        .hero-tag {
            display: inline-block;
            font-size: 12px;
            font-weight: 600;
            letter-spacing: 0.08em;
            color: var(--color-accent);
            text-transform: uppercase;
            margin-bottom: 16px;
        }

        .hero-title {
            font-size: clamp(36px, 4.5vw, 54px);
            font-weight: 700;
            line-height: 1.15;
            letter-spacing: -0.02em;
            color: var(--color-text-primary);
            margin-bottom: 16px;
        }

        .hero-subtitle {
            font-size: 18px;
            color: var(--color-text-secondary);
            line-height: 1.6;
            max-width: 460px;
            margin-bottom: 32px;
        }

        @media (max-width: 768px) {
            .hero-subtitle {
                max-width: 100%;
                margin-left: auto;
                margin-right: auto;
            }
        }

        .hero-cta-group {
            display: flex;
            gap: 16px;
            flex-wrap: wrap;
        }

        @media (max-width: 768px) {
            .hero-cta-group {
                justify-content: center;
            }
            .hero-cta-group .btn {
                width: 100%;
                justify-content: center;
                text-align: center;
            }
        }

        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 14px 32px;
            font-size: 15px;
            font-weight: 600;
            border-radius: var(--btn-radius);
            transition: all var(--transition-fast);
            cursor: pointer;
            text-decoration: none;
            line-height: 1.4;
            white-space: nowrap;
        }

        .btn-primary {
            background-color: var(--color-primary);
            color: #fff;
            border: 1.5px solid var(--color-primary);
        }
        .btn-primary:hover {
            background-color: var(--color-primary-dark);
            border-color: var(--color-primary-dark);
            transform: scale(1.03);
            box-shadow: 0 4px 16px rgba(74, 55, 40, 0.25);
        }
        .btn-primary:active {
            transform: scale(0.98);
        }

        .btn-ghost {
            background-color: transparent;
            color: var(--color-primary);
            border: 1.5px solid var(--color-primary);
        }
        .btn-ghost:hover {
            background-color: var(--color-primary);
            color: #fff;
            transform: scale(1.03);
        }
        .btn-ghost:active {
            transform: scale(0.98);
        }

        .btn-accent {
            background-color: var(--color-accent);
            color: #fff;
            border: 1.5px solid var(--color-accent);
        }
        .btn-accent:hover {
            background-color: var(--color-accent-light);
            border-color: var(--color-accent-light);
            transform: scale(1.03);
            box-shadow: 0 4px 16px rgba(184, 134, 63, 0.3);
        }
        .btn-accent:active {
            transform: scale(0.98);
        }

        .hero-visual-inner {
            width: 100%;
            aspect-ratio: 4 / 3;
            border-radius: 16px;
            overflow: hidden;
            position: relative;
            background-color: var(--color-bg-secondary);
            border: 1px solid var(--color-border);
        }

        .hero-visual-inner img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        .hero-visual-overlay {
            position: absolute;
            inset: 0;
            background: linear-gradient(135deg, rgba(74, 55, 40, 0.06) 0%, transparent 50%, rgba(90, 107, 77, 0.04) 100%);
            pointer-events: none;
        }

        .hero-visual-dots {
            position: absolute;
            bottom: 16px;
            right: 20px;
            display: flex;
            gap: 6px;
            pointer-events: none;
        }
        .hero-visual-dots span {
            width: 5px;
            height: 5px;
            border-radius: 50%;
            background-color: var(--color-accent);
            opacity: 0.5;
            animation: dotPulse 2s ease-in-out infinite;
        }
        .hero-visual-dots span:nth-child(2) {
            animation-delay: 0.3s;
        }
        .hero-visual-dots span:nth-child(3) {
            animation-delay: 0.6s;
        }

        @keyframes dotPulse {
            0%,
            100% {
                opacity: 0.35;
                transform: scale(1);
            }
            50% {
                opacity: 0.8;
                transform: scale(1.5);
            }
        }

        /* Section common */
        .section {
            padding: 120px 0;
        }
        @media (max-width: 768px) {
            .section {
                padding: 72px 0;
            }
        }

        .section-label {
            text-align: center;
            font-size: 13px;
            font-weight: 600;
            letter-spacing: 0.06em;
            color: var(--color-accent);
            text-transform: uppercase;
            margin-bottom: 8px;
        }

        .section-title {
            font-size: clamp(28px, 3.5vw, 40px);
            font-weight: 600;
            line-height: 1.25;
            color: var(--color-text-primary);
            text-align: center;
            margin-bottom: 12px;
        }

        .section-subtitle {
            font-size: 16px;
            color: var(--color-text-secondary);
            text-align: center;
            max-width: 560px;
            margin: 0 auto 48px;
            line-height: 1.6;
        }

        @media (max-width: 768px) {
            .section-subtitle {
                margin-bottom: 32px;
                font-size: 15px;
            }
        }

        /* Features */
        #features {
            background-color: var(--color-white);
        }

        .features-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 28px;
        }

        @media (max-width: 1024px) {
            .features-grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }
        @media (max-width: 768px) {
            .features-grid {
                grid-template-columns: 1fr;
                gap: 18px;
            }
        }

        .feature-card {
            background-color: #fff;
            border-radius: var(--card-radius);
            padding: 32px;
            border: 1px solid var(--color-border);
            box-shadow: var(--shadow-card);
            transition: all var(--transition-smooth);
            text-align: left;
        }

        .feature-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--shadow-card-hover);
        }

        .feature-icon-wrap {
            width: 48px;
            height: 48px;
            border-radius: 50%;
            background-color: rgba(90, 107, 77, 0.1);
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 16px;
            transition: background-color var(--transition-smooth);
        }

        .feature-card:hover .feature-icon-wrap {
            background-color: rgba(90, 107, 77, 0.18);
        }

        .feature-icon-wrap svg {
            width: 22px;
            height: 22px;
            color: var(--color-secondary);
        }

        .feature-card h3 {
            font-size: 22px;
            font-weight: 600;
            color: var(--color-text-primary);
            margin-bottom: 8px;
            line-height: 1.35;
        }

        .feature-card p {
            font-size: 15px;
            color: var(--color-text-secondary);
            line-height: 1.65;
            margin: 0;
            max-width: 100%;
        }

        /* Stats */
        #stats {
            background-color: var(--color-primary);
            position: relative;
            overflow: hidden;
        }

        #stats::before {
            content: '';
            position: absolute;
            inset: 0;
            pointer-events: none;
            opacity: 0.04;
            background-image:
                linear-gradient(rgba(255, 255, 255, 0.3) 0.5px, transparent 0.5px),
                linear-gradient(90deg, rgba(255, 255, 255, 0.3) 0.5px, transparent 0.5px);
            background-size: 40px 40px;
            z-index: 0;
        }

        #stats .section-title {
            color: #fff;
            position: relative;
            z-index: 1;
        }
        #stats .section-subtitle {
            color: rgba(255, 255, 255, 0.7);
            position: relative;
            z-index: 1;
        }

        .stats-grid {
            display: flex;
            justify-content: center;
            gap: 0;
            flex-wrap: wrap;
            position: relative;
            z-index: 1;
        }

        .stat-item {
            flex: 1 1 200px;
            max-width: 240px;
            text-align: center;
            padding: 20px 24px;
            position: relative;
        }

        .stat-item+.stat-item {
            border-left: 1px solid rgba(184, 134, 63, 0.3);
        }

        @media (max-width: 768px) {
            .stats-grid {
                gap: 0;
                display: grid;
                grid-template-columns: 1fr 1fr;
            }
            .stat-item {
                max-width: 100%;
                flex: none;
                padding: 18px 12px;
            }
            .stat-item:nth-child(odd)+.stat-item {
                border-left: none;
            }
            .stat-item:nth-child(3) {
                border-left: 1px solid rgba(184, 134, 63, 0.3);
            }
            .stat-item:nth-child(1),
            .stat-item:nth-child(2) {
                border-bottom: 1px solid rgba(184, 134, 63, 0.3);
            }
        }

        .stat-number {
            font-size: clamp(36px, 4vw, 48px);
            font-weight: 700;
            color: var(--color-accent);
            font-family: var(--font-mono);
            letter-spacing: -0.02em;
            line-height: 1.1;
            margin-bottom: 8px;
        }

        .stat-label {
            font-size: 14px;
            font-weight: 400;
            color: rgba(255, 255, 255, 0.8);
            letter-spacing: 0.03em;
        }

        /* Solutions */
        #solutions {
            background-color: var(--color-bg-primary);
        }

        .solution-row {
            display: flex;
            align-items: center;
            gap: 60px;
            margin-bottom: 100px;
        }

        .solution-row:last-child {
            margin-bottom: 0;
        }

        .solution-row.reverse {
            flex-direction: row-reverse;
        }

        @media (max-width: 768px) {
            .solution-row,
            .solution-row.reverse {
                flex-direction: column;
                gap: 32px;
                margin-bottom: 64px;
            }
        }

        .solution-text {
            flex: 0 0 50%;
            max-width: 50%;
        }

        @media (max-width: 768px) {
            .solution-text {
                flex: 1 1 auto;
                max-width: 100%;
                order: 2;
            }
        }

        .solution-image {
            flex: 0 0 45%;
            max-width: 45%;
            aspect-ratio: 4 / 3;
            border-radius: 12px;
            overflow: hidden;
            border: 1px solid var(--color-border);
            background-color: var(--color-bg-secondary);
            transition: transform var(--transition-smooth), box-shadow var(--transition-smooth);
        }

        .solution-image:hover {
            transform: scale(1.02);
            box-shadow: var(--shadow-card-hover);
        }

        .solution-image img {
            width: 100%;
            height: 100%;
            object-fit: cover;
        }

        @media (max-width: 768px) {
            .solution-image {
                flex: 1 1 auto;
                max-width: 100%;
                order: 1;
                width: 100%;
            }
        }

        .solution-tag {
            display: inline-block;
            font-size: 12px;
            font-weight: 600;
            letter-spacing: 0.06em;
            color: var(--color-accent);
            background-color: rgba(184, 134, 63, 0.08);
            padding: 4px 12px;
            border-radius: 20px;
            margin-bottom: 12px;
            text-transform: uppercase;
        }

        .solution-text h3 {
            font-size: clamp(22px, 2.5vw, 26px);
            font-weight: 600;
            color: var(--color-text-primary);
            margin-bottom: 12px;
            line-height: 1.35;
        }

        .solution-text p {
            font-size: 16px;
            color: var(--color-text-secondary);
            line-height: 1.7;
            margin-bottom: 16px;
            max-width: 520px;
        }

        .solution-features {
            list-style: none;
            padding: 0;
            margin: 0;
        }

        .solution-features li {
            font-size: 15px;
            color: var(--color-text-primary);
            line-height: 1.6;
            padding-left: 22px;
            position: relative;
            margin-bottom: 8px;
        }

        .solution-features li::before {
            content: '';
            position: absolute;
            left: 0;
            top: 9px;
            width: 10px;
            height: 2px;
            background-color: var(--color-accent);
            border-radius: 1px;
        }

        /* FAQ */
        #faq {
            background-color: var(--color-bg-secondary);
        }

        .faq-container {
            max-width: 720px;
            margin: 0 auto;
        }

        .faq-item {
            border-bottom: 1px solid var(--color-border);
            cursor: pointer;
        }

        .faq-question {
            display: flex;
            align-items: center;
            justify-content: space-between;
            padding: 20px 0;
            font-size: 18px;
            font-weight: 500;
            color: var(--color-text-primary);
            transition: color var(--transition-fast);
            user-select: none;
            gap: 16px;
        }

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

        .faq-arrow {
            flex-shrink: 0;
            width: 20px;
            height: 20px;
            transition: transform var(--transition-smooth);
            color: var(--color-text-secondary);
        }

        .faq-item.open .faq-arrow {
            transform: rotate(180deg);
            color: var(--color-primary);
        }

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

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

        .faq-answer p {
            font-size: 15px;
            color: var(--color-text-secondary);
            line-height: 1.7;
            margin: 0;
        }

        /* CTA */
        #cta {
            background-color: var(--color-secondary);
            text-align: center;
            position: relative;
            overflow: hidden;
        }

        #cta::before {
            content: '';
            position: absolute;
            inset: 0;
            pointer-events: none;
            opacity: 0.05;
            background: radial-gradient(circle at 30% 50%, rgba(255, 255, 255, 0.3) 0%, transparent 60%),
                radial-gradient(circle at 70% 50%, rgba(255, 255, 255, 0.2) 0%, transparent 50%);
            z-index: 0;
        }

        #cta .section-title {
            color: #fff;
            position: relative;
            z-index: 1;
            font-size: clamp(26px, 3vw, 36px);
        }

        #cta .section-subtitle {
            color: rgba(255, 255, 255, 0.8);
            position: relative;
            z-index: 1;
            margin-bottom: 32px;
        }

        #cta .btn-accent {
            position: relative;
            z-index: 1;
            font-size: 16px;
            padding: 16px 40px;
        }

        @media (max-width: 768px) {
            #cta .btn-accent {
                width: 100%;
                max-width: 320px;
            }
        }

        /* Footer */
        #footer {
            background-color: var(--color-primary);
            color: #fff;
            padding: 64px 0 32px;
        }

        @media (max-width: 768px) {
            #footer {
                padding: 48px 0 24px;
            }
        }

        .footer-inner {
            display: flex;
            gap: 48px;
            flex-wrap: wrap;
            justify-content: space-between;
            margin-bottom: 40px;
        }

        @media (max-width: 768px) {
            .footer-inner {
                flex-direction: column;
                gap: 32px;
                margin-bottom: 28px;
            }
        }

        .footer-col {
            flex: 1 1 auto;
            min-width: 180px;
        }

        .footer-logo {
            font-size: 20px;
            font-weight: 700;
            color: #fff;
            margin-bottom: 10px;
            letter-spacing: 0.02em;
        }

        .footer-col p {
            font-size: 14px;
            color: rgba(255, 255, 255, 0.6);
            line-height: 1.6;
            margin: 0;
            max-width: 240px;
        }

        .footer-links {
            list-style: none;
            padding: 0;
            margin: 0;
        }

        .footer-links li {
            margin-bottom: 8px;
        }

        .footer-links a {
            font-size: 14px;
            color: rgba(255, 255, 255, 0.7);
            transition: color var(--transition-fast);
            text-decoration: none;
        }

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

        .footer-bottom {
            border-top: 1px solid rgba(255, 255, 255, 0.15);
            padding-top: 20px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            flex-wrap: wrap;
            gap: 12px;
            font-size: 13px;
            color: rgba(255, 255, 255, 0.5);
        }

        @media (max-width: 768px) {
            .footer-bottom {
                flex-direction: column;
                text-align: center;
                gap: 6px;
            }
        }

        /* Fade-in animation */
        .fade-in-up {
            opacity: 0;
            transform: translateY(24px);
            transition: opacity 0.6s ease, transform 0.6s ease;
        }
        .fade-in-up.visible {
            opacity: 1;
            transform: translateY(0);
        }

        .fade-in-up-delay-1 {
            transition-delay: 0.1s;
        }
        .fade-in-up-delay-2 {
            transition-delay: 0.2s;
        }
        .fade-in-up-delay-3 {
            transition-delay: 0.3s;
        }
        .fade-in-up-delay-4 {
            transition-delay: 0.4s;
        }

        @media (prefers-reduced-motion: reduce) {
            .fade-in-up {
                transition: none;
                opacity: 1;
                transform: none;
            }
            .hero-visual-dots span {
                animation: none;
            }
        }

        /* Focus accessibility */
        a:focus-visible,
        button:focus-visible {
            outline: 2px solid var(--color-accent);
            outline-offset: 2px;
            border-radius: 2px;
        }

        /* Skip to content */
        .skip-link {
            position: absolute;
            top: -100px;
            left: 16px;
            background: var(--color-primary);
            color: #fff;
            padding: 8px 16px;
            border-radius: 4px;
            z-index: 9999;
            font-size: 14px;
            transition: top 0.3s;
        }
        .skip-link:focus {
            top: 10px;
        }