/* ── Reset & Base ── */
        *,
        *::before,
        *::after {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }
        body {
            font-family: 'Inter', -apple-system, system-ui, sans-serif;
            background: #ffffff;  /* 纯白背景 */
            color: #1e1c1a;
            line-height: 1.6;
            -webkit-font-smoothing: antialiased;
        }
        img {
            max-width: 100%;
            height: auto;
            display: block;
        }
        a {
            text-decoration: none;
            color: inherit;
        }
        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 24px;
        }

        /* ── Typography ── */
        .eyebrow {
            font-size: 0.75rem;
            letter-spacing: 0.12em;
            text-transform: uppercase;
            color: #8a7a6a;
            font-weight: 600;
            margin-bottom: 0.5rem;
        }
        .section-title {
            font-family: 'Playfair Display', serif;
            font-size: 2.6rem;
            font-weight: 700;
            letter-spacing: -0.02em;
            line-height: 1.2;
            margin-bottom: 1rem;
        }
        .section-title span {
            color: #5a3e2b;
        }
        .lead {
            font-size: 1.2rem;
            color: #4a3f38;
            max-width: 640px;
            font-weight: 400;
            line-height: 1.7;
        }

        /* ── Button ── */
        .btn-primary {
            display: inline-block;
            padding: 14px 40px;
            background: #3d281b;
            color: #ffffff;
            font-weight: 600;
            font-size: 1rem;
            border-radius: 60px;
            border: none;
            transition: all 0.3s ease;
            cursor: pointer;
            letter-spacing: 0.02em;
            box-shadow: 0 4px 20px rgba(61, 40, 27, 0.15);
        }
        .btn-primary:hover {
            background: #5a3e2b;
            transform: translateY(-3px);
            box-shadow: 0 8px 30px rgba(61, 40, 27, 0.25);
        }
        .btn-outline {
            display: inline-block;
            padding: 14px 40px;
            background: transparent;
            color: #3d281b;
            font-weight: 600;
            font-size: 1rem;
            border-radius: 60px;
            border: 2px solid #3d281b;
            transition: all 0.3s ease;
            cursor: pointer;
        }
        .btn-outline:hover {
            background: #3d281b;
            color: #ffffff;
        }

        /* ── Hero (纯白背景) ── */
        .hero {
            padding: 60px 0 80px;
            background: #ffffff;
            position: relative;
        }
        .hero-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 60px;
            align-items: center;
        }
        .hero-content .badge {
            display: inline-block;
            background: #3d281b;
            color: #ffffff;
            font-size: 0.7rem;
            font-weight: 600;
            letter-spacing: 0.08em;
            padding: 6px 18px;
            border-radius: 40px;
            margin-bottom: 1.2rem;
            text-transform: uppercase;
        }
        .hero-content h1 {
            font-family: 'Playfair Display', serif;
            font-size: 3.8rem;
            font-weight: 700;
            line-height: 1.1;
            letter-spacing: -0.03em;
            margin-bottom: 1rem;
            color: #1e1c1a;
        }
        .hero-content h1 em {
            font-style: italic;
            color: #5a3e2b;
        }
        .hero-content .lead {
            font-size: 1.25rem;
            color: #4a3f38;
            margin-bottom: 1.5rem;
            max-width: 500px;
        }
        .hero-proof {
            display: flex;
            flex-wrap: wrap;
            gap: 20px 32px;
            margin-top: 2rem;
            padding-top: 2rem;
            border-top: 1px solid #e8e0d8;
        }
        .hero-proof span {
            font-size: 0.9rem;
            font-weight: 500;
            color: #3d281b;
            display: flex;
            align-items: center;
            gap: 8px;
        }
        .hero-proof span::before {
            content: '✦';
            color: #8a7a6a;
            font-size: 0.7rem;
        }
        .hero-visual {
            display: flex;
            flex-direction: column;
            align-items: center;
            justify-content: center;
        }
        .hero-visual .frame-mockup {
            width: 100%;
            max-width: 520px;
            border-radius: 12px;
            box-shadow: 0 40px 80px rgba(0, 0, 0, 0.06);
            background: #f5f0eb;
            padding: 16px 16px 20px;
            transition: transform 0.6s ease;
        }
        .hero-visual .frame-mockup:hover {
            transform: perspective(1000px) rotateY(-2deg) rotateX(1deg);
        }
        .hero-visual .frame-mockup img {
            border-radius: 6px;
            background: #d6cbc0;
            aspect-ratio: 4/3;
            object-fit: cover;
            width: 100%;
        }
        .hero-visual .wood-badge {
            margin-top: 20px;
            font-size: 0.85rem;
            color: #5a3e2b;
            font-weight: 500;
            letter-spacing: 0.04em;
            display: flex;
            align-items: center;
            gap: 10px;
        }
        .hero-visual .wood-badge::before {
            content: '';
            width: 32px;
            height: 4px;
            background: #5a3e2b;
            border-radius: 4px;
        }

        /* ── 各区块统一纯白背景，仅用边框或阴影分割 ── */
        .walnut-story,
        .features,
        .specs,
        .compare-section,
        .ai-section,
        .apps,
        .faq,
        .download-section {
            padding: 80px 0;
            background: #ffffff;
            border-bottom: 1px solid #f0ece7;
        }
        .download-section {
            border-bottom: none;
        }

        /* ── Walnut Story ── */
        .walnut-story .grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 70px;
            align-items: center;
        }
        .walnut-story .text-block h2 {
            font-family: 'Playfair Display', serif;
            font-size: 2.8rem;
            font-weight: 700;
            line-height: 1.2;
            margin-bottom: 1.2rem;
        }
        .walnut-story .text-block h2 em {
            font-style: italic;
            color: #5a3e2b;
        }
        .walnut-story .text-block p {
            color: #4a3f38;
            font-size: 1.05rem;
            line-height: 1.8;
            margin-bottom: 1.2rem;
        }
        .walnut-story .grain-gallery {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 16px;
        }
        .walnut-story .grain-gallery .grain-item {
            border-radius: 12px;
            overflow: hidden;
            background: #ede5dc;
            aspect-ratio: 1/1;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 0.75rem;
            color: #8a7a6a;
            font-weight: 500;
            text-transform: uppercase;
            letter-spacing: 0.04em;
            background-size: cover;
            background-position: center;
            transition: transform 0.4s ease;
        }
        .walnut-story .grain-gallery .grain-item:hover {
            transform: scale(1.02);
        }
        .grain-item:nth-child(1) {
            background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 400 400"><rect fill="%235a3e2b" width="400" height="400"/><path d="M0 0L400 400M200 0L400 200M0 200L200 400M0 100L300 400M100 0L400 300" stroke="%237a5a42" stroke-width="2" opacity="0.3"/><path d="M0 300L400 100M50 0L400 350M350 400L0 50" stroke="%234a2a1a" stroke-width="1.5" opacity="0.2"/></svg>');
        }
        .grain-item:nth-child(2) {
            background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 400 400"><rect fill="%236a4e3a" width="400" height="400"/><circle cx="200" cy="200" r="180" fill="%235a3e2b" opacity="0.5"/><circle cx="200" cy="200" r="120" fill="%237a5a42" opacity="0.3"/><circle cx="200" cy="200" r="60" fill="%234a2a1a" opacity="0.2"/><path d="M0 200L400 200M200 0L200 400" stroke="%237a5a42" stroke-width="1.5" opacity="0.2"/></svg>');
        }
        .grain-item:nth-child(3) {
            background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 400 400"><rect fill="%234a2a1a" width="400" height="400"/><path d="M0 100L400 100M0 200L400 200M0 300L400 300M0 400L400 400" stroke="%237a5a42" stroke-width="1.5" opacity="0.15"/><path d="M50 0L50 400M150 0L150 400M250 0L250 400M350 0L350 400" stroke="%237a5a42" stroke-width="1.5" opacity="0.1"/></svg>');
        }
        .grain-item:nth-child(4) {
            background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 400 400"><rect fill="%235a3e2b" width="400" height="400"/><circle cx="200" cy="200" r="160" fill="%234a2a1a" opacity="0.3"/><circle cx="200" cy="200" r="100" fill="%237a5a42" opacity="0.2"/><circle cx="200" cy="200" r="50" fill="%234a2a1a" opacity="0.15"/><path d="M0 0L400 400M0 400L400 0" stroke="%237a5a42" stroke-width="1" opacity="0.1"/></svg>');
        }

        /* ── Features ── */
        .features .grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 30px;
            margin-top: 50px;
        }
        .feature-card {
            padding: 36px 30px;
            border-radius: 16px;
            background: #faf8f5;
            border: 1px solid #ede5dc;
            transition: all 0.3s ease;
        }
        .feature-card:hover {
            transform: translateY(-6px);
            box-shadow: 0 20px 50px rgba(61, 40, 27, 0.05);
            border-color: #d6cbc0;
        }
        .feature-card .icon {
            font-size: 2.2rem;
            margin-bottom: 1rem;
            display: block;
        }
        .feature-card h3 {
            font-family: 'Playfair Display', serif;
            font-size: 1.4rem;
            font-weight: 600;
            margin-bottom: 0.6rem;
            color: #1e1c1a;
        }
        .feature-card p {
            color: #4a3f38;
            font-size: 0.95rem;
            line-height: 1.7;
        }

        /* ── Specs ── */
        .specs-grid {
            display: grid;
            grid-template-columns: repeat(2, 1fr);
            gap: 30px;
            margin-top: 40px;
        }
        .spec-item {
            display: flex;
            justify-content: space-between;
            padding: 14px 0;
            border-bottom: 1px solid #f0ece7;
        }
        .spec-item .label {
            font-weight: 500;
            color: #3d281b;
        }
        .spec-item .value {
            color: #4a3f38;
            text-align: right;
        }

        /* ── Comparison ── */
        .compare-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 40px;
            margin-top: 50px;
        }
        .compare-card {
            padding: 36px 32px;
            border-radius: 16px;
            border: 1px solid #ede5dc;
            background: #faf8f5;
            transition: all 0.3s ease;
        }
        .compare-card.recommended {
            border-color: #3d281b;
            background: #f5f0eb;
            position: relative;
        }
        .compare-card.recommended::before {
            content: '★ Recommended';
            position: absolute;
            top: -12px;
            right: 24px;
            background: #3d281b;
            color: #ffffff;
            font-size: 0.7rem;
            font-weight: 600;
            letter-spacing: 0.04em;
            padding: 4px 16px;
            border-radius: 40px;
        }
        .compare-card h3 {
            font-family: 'Playfair Display', serif;
            font-size: 1.4rem;
            margin-bottom: 1.2rem;
        }
        .compare-card ul {
            list-style: none;
            padding: 0;
        }
        .compare-card ul li {
            padding: 8px 0 8px 28px;
            position: relative;
            color: #4a3f38;
            font-size: 0.95rem;
            border-bottom: 1px solid rgba(61, 40, 27, 0.05);
        }
        .compare-card ul li:last-child {
            border-bottom: none;
        }
        .compare-card ul li::before {
            content: '✓';
            position: absolute;
            left: 0;
            color: #3d281b;
            font-weight: 700;
        }
        .compare-card.conventional ul li::before {
            content: '✕';
            color: #b8a89a;
        }

        /* ── AI + Gallery ── */
        .ai-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 60px;
            align-items: center;
            margin-top: 40px;
        }
        .ai-grid .copy h2 {
            font-family: 'Playfair Display', serif;
            font-size: 2.6rem;
            font-weight: 700;
            line-height: 1.2;
            margin-bottom: 1rem;
        }
        .ai-grid .copy p {
            color: #4a3f38;
            font-size: 1.05rem;
            line-height: 1.8;
            margin-bottom: 1.5rem;
        }
        .ai-grid .steps {
            display: flex;
            flex-direction: column;
            gap: 16px;
        }
        .ai-grid .steps .step {
            display: flex;
            align-items: center;
            gap: 16px;
            padding: 14px 20px;
            background: #ffffff;
            border-radius: 12px;
            border: 1px solid #ede5dc;
        }
        .ai-grid .steps .step .num {
            width: 32px;
            height: 32px;
            background: #3d281b;
            color: #ffffff;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            font-size: 0.9rem;
            flex-shrink: 0;
        }
        .ai-grid .steps .step span {
            font-weight: 500;
            color: #1e1c1a;
        }

        /* ── Applications ── */
        .apps-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 30px;
            margin-top: 40px;
        }
        .app-card {
            border-radius: 16px;
            overflow: hidden;
            background: #faf8f5;
            border: 1px solid #ede5dc;
            transition: all 0.3s ease;
        }
        .app-card:hover {
            transform: translateY(-4px);
            box-shadow: 0 16px 40px rgba(61, 40, 27, 0.05);
        }
        .app-card .app-img {
            height: 200px;
            background: #ede5dc;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 3rem;
            color: #8a7a6a;
        }
        .app-card .app-body {
            padding: 24px 24px 28px;
        }
        .app-card .app-body h4 {
            font-family: 'Playfair Display', serif;
            font-size: 1.2rem;
            margin-bottom: 0.5rem;
        }
        .app-card .app-body p {
            color: #4a3f38;
            font-size: 0.95rem;
            line-height: 1.7;
        }

        /* ── FAQ ── */
        .faq-grid {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 20px 40px;
            margin-top: 40px;
        }
        .faq-item details {
            padding: 20px 0;
            border-bottom: 1px solid #f0ece7;
            cursor: pointer;
        }
        .faq-item details summary {
            font-weight: 600;
            font-size: 1.05rem;
            color: #1e1c1a;
            list-style: none;
            display: flex;
            justify-content: space-between;
            align-items: center;
        }
        .faq-item details summary::after {
            content: '+';
            font-size: 1.4rem;
            color: #3d281b;
            transition: transform 0.3s ease;
        }
        .faq-item details[open] summary::after {
            content: '−';
        }
        .faq-item details p {
            color: #4a3f38;
            padding-top: 12px;
            line-height: 1.7;
            font-size: 0.95rem;
        }

        /* ── Download Section ── */
        .download-grid {
            display: flex;
            flex-wrap: wrap;
            gap: 24px;
            justify-content: center;
            margin-top: 30px;
        }
        .download-card {
            background: #faf8f5;
            border: 1px solid #ede5dc;
            border-radius: 16px;
            padding: 24px 32px;
            display: flex;
            align-items: center;
            gap: 20px;
            transition: all 0.3s ease;
            min-width: 260px;
            flex: 1 0 auto;
            max-width: 400px;
        }
        .download-card:hover {
            transform: translateY(-4px);
            box-shadow: 0 12px 30px rgba(61, 40, 27, 0.06);
            border-color: #d6cbc0;
        }
        .download-card .dl-icon {
            font-size: 2rem;
            color: #3d281b;
        }
        .download-card .dl-info h4 {
            font-weight: 600;
            font-size: 1rem;
            margin-bottom: 0.2rem;
            color: #1e1c1a;
        }
        .download-card .dl-info p {
            font-size: 0.85rem;
            color: #8a7a6a;
        }
        .download-card .dl-link {
            margin-left: auto;
            background: #3d281b;
            color: #fff;
            padding: 8px 18px;
            border-radius: 40px;
            font-size: 0.8rem;
            font-weight: 500;
            transition: 0.3s;
        }
        .download-card .dl-link:hover {
            background: #5a3e2b;
        }

        /* ── CTA (纯白背景，但保留一点装饰) ── */
        .cta-section {
            padding: 80px 0;
            background: #faf8f5;
            text-align: center;
            border-top: 1px solid #f0ece7;
            border-bottom: 1px solid #f0ece7;
        }
        .cta-section h2 {
            font-family: 'Playfair Display', serif;
            font-size: 2.8rem;
            font-weight: 700;
            margin-bottom: 1rem;
        }
        .cta-section h2 em {
            font-style: italic;
            color: #5a3e2b;
        }
        .cta-section .lead {
            color: #4a3f38;
            max-width: 600px;
            margin: 0 auto 2rem;
        }
        .cta-section .btn-primary {
            background: #3d281b;
            color: #ffffff;
        }
        .cta-section .btn-primary:hover {
            background: #5a3e2b;
        }

        /* ── Footer (纯白背景，无黑色框) ── */
        .footer {
            padding: 40px 0;
            background: #ffffff;
            color: #4a3f38;
            font-size: 0.9rem;
            text-align: center;
            border-top: 1px solid #f0ece7;
        }
        .footer a {
            color: #3d281b;
            font-weight: 500;
        }
        .footer .footer-tagline {
            margin-top: 8px;
            font-size: 0.8rem;
            color: #8a7a6a;
            letter-spacing: 0.03em;
        }

        /* ── Responsive ── */
        @media (max-width: 1024px) {
            .hero-grid {
                grid-template-columns: 1fr;
                gap: 40px;
                text-align: center;
            }
            .hero-content .lead {
                max-width: 100%;
                margin-left: auto;
                margin-right: auto;
            }
            .hero-proof {
                justify-content: center;
            }
            .hero-visual .frame-mockup {
                max-width: 400px;
            }
            .walnut-story .grid {
                grid-template-columns: 1fr;
                gap: 40px;
            }
            .walnut-story .grain-gallery {
                grid-template-columns: 1fr 1fr;
            }
            .features .grid {
                grid-template-columns: 1fr 1fr;
            }
            .specs-grid {
                grid-template-columns: 1fr;
            }
            .compare-grid {
                grid-template-columns: 1fr;
            }
            .ai-grid {
                grid-template-columns: 1fr;
                gap: 40px;
            }
            .apps-grid {
                grid-template-columns: 1fr 1fr;
            }
            .faq-grid {
                grid-template-columns: 1fr;
            }
            .download-grid {
                flex-direction: column;
                align-items: center;
            }
            .download-card {
                max-width: 100%;
                width: 100%;
            }
        }
        @media (max-width: 640px) {
            .hero-content h1 {
                font-size: 2.6rem;
            }
            .section-title {
                font-size: 2rem;
            }
            .features .grid {
                grid-template-columns: 1fr;
            }
            .apps-grid {
                grid-template-columns: 1fr;
            }
            .compare-card.recommended::before {
                position: static;
                display: inline-block;
                margin-bottom: 12px;
            }
            .walnut-story .grain-gallery {
                grid-template-columns: 1fr 1fr;
                gap: 10px;
            }
            .walnut-story .text-block h2 {
                font-size: 2rem;
            }
            .ai-grid .copy h2 {
                font-size: 2rem;
            }
            .cta-section h2 {
                font-size: 2rem;
            }
            .hero-proof {
                gap: 12px 20px;
            }
            .hero-proof span {
                font-size: 0.8rem;
            }
            .btn-primary,
            .btn-outline {
                padding: 12px 28px;
                font-size: 0.9rem;
            }
            .download-card {
                flex-wrap: wrap;
                justify-content: center;
                text-align: center;
            }
            .download-card .dl-link {
                margin-left: 0;
            }
        }