:root {
            --color-text: #222;
            --color-heading: #1a1a1a;
            --color-border: #e0e0e0;
            --color-card-border: #e8e8e8;
            --color-bg-light: #f8f8f8;
            --color-bg-img: #f5f5f5;
            --color-white: #fff;
            --color-border-hover: #ccc;
            --color-icon: #888;
            --color-shadow: rgba(0, 0, 0, 0.04);
            --font-family: 'Poppins', sans-serif;
            --radius: 6px;
            --shadow-card: 0 4px 12px var(--color-shadow);
            --transition: 0.2s ease;
            --max-width: 1440px;
            --gap-lg: 50px;
            --gap-md: 30px;
            --gap-sm: 20px;
        }

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

        body {
            font-family: var(--font-family);
            font-weight: 400;
            font-size: 16px;
            line-height: 1.6;
            color: var(--color-text);
            background: var(--color-white);
            -webkit-font-smoothing: antialiased;
        }

        .page-wrap {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 40px 24px 60px;
        }

        h2 {
            font-family: var(--font-family);
            font-weight: 700;
            font-size: 28px;
            line-height: 1.3;
            color: var(--color-heading);
            margin: 0 0 12px 0;
            letter-spacing: -0.01em;
        }

        h3 {
            font-family: var(--font-family);
            font-weight: 400;
            font-size: 20px;
            line-height: 1.4;
            color: var(--color-heading);
            margin: 0 0 10px 0;
        }

        p {
            font-family: var(--font-family);
            font-size: 16px;
            line-height: 1.7;
            color: var(--color-text);
            margin: 0 0 14px 0;
        }

        .module {
            margin-bottom: 60px;
        }
        .module:last-child {
            margin-bottom: 0;
        }

        .structure-wrap {
            display: flex;
            flex-wrap: wrap;
            align-items: flex-start;
            gap: 40px var(--gap-lg);
        }

        .structure-text {
            flex: 1 1 52%;
            min-width: 280px;
        }

        .structure-text .layer {
            margin-bottom: 20px;
        }
        .structure-text .layer:last-child {
            margin-bottom: 0;
        }

        .structure-text .layer h3 {
            font-size: 18px;
            font-weight: 400;
            margin-bottom: 6px;
        }

        .structure-text .layer p {
            margin-bottom: 0;
        }

        .structure-image {
            flex: 0 1 38%;
            min-width: 240px;
        }

        .structure-image img {
            width: 100%;
            max-width: 420px;
            display: block;
            border-radius: var(--radius);
            background: var(--color-bg-img);
        }

        .spec-table-wrap {
            overflow-x: auto;
            -webkit-overflow-scrolling: touch;
            margin-top: 6px;
            border-radius: var(--radius);
        }

        .spec-table {
            width: 100%;
            border-collapse: collapse;
            font-size: 16px;
            background: var(--color-white);
        }

        .spec-table thead th {
            padding: 12px 18px;
            text-align: left;
            font-weight: 700;
            background: var(--color-bg-light);
            border-bottom: 2px solid var(--color-border);
            color: var(--color-heading);
        }

        .spec-table td,
        .spec-table th {
            padding: 12px 18px;
            border: 1px solid var(--color-border);
            vertical-align: middle;
            text-align: left;
        }

        .spec-table .label-cell {
            font-weight: 700;
            background: var(--color-bg-light);
            width: 32%;
            min-width: 140px;
        }

        .features-text ul {
            list-style: disc;
            padding-left: 20px;
            margin: 0;
        }

        .features-text ul li {
            font-size: 16px;
            line-height: 1.7;
            color: var(--color-text);
            margin-bottom: 4px;
            padding: 0;
        }

        .app-intro {
            margin-bottom: 28px;
        }
        .app-intro p {
            margin-bottom: 0;
        }

        .app-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: var(--gap-md);
            margin-top: 10px;
        }

        .app-card {
            background: var(--color-white);
            border: 1px solid var(--color-card-border);
            border-radius: var(--radius);
            padding: 20px 20px 18px;
            display: flex;
            flex-direction: column;
            transition: box-shadow var(--transition), transform var(--transition);
        }

        .app-card:hover {
            box-shadow: var(--shadow-card);
            transform: translateY(-2px);
        }

        .app-card .app-img {
            width: 100%;
            aspect-ratio: 4 / 3;
            object-fit: cover;
            display: block;
            border-radius: 4px;
            background: var(--color-bg-img);
            margin-bottom: 14px;
            transition: transform 0.3s ease;
        }

        .app-card:hover .app-img {
            transform: scale(1.01);
        }

        .app-card h3 {
            font-size: 19px;
            font-weight: 400;
            margin-bottom: 6px;
            color: var(--color-heading);
        }

        .app-card .desc {
            margin-bottom: 10px;
        }

        .app-card .app-list {
            flex-shrink: 0;
        }

        .app-card .app-list p {
            margin-bottom: 2px;
            font-size: 15px;
            font-weight: 400;
            color: var(--color-heading);
        }

        .app-card .app-list ul {
            list-style: disc;
            padding-left: 20px;
            margin: 4px 0 0;
        }

        .app-card .app-list ul li {
            font-size: 15px;
            line-height: 1.8;
            color: var(--color-text);
            margin-bottom: 0;
        }

        .factory-wrap {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: 40px var(--gap-lg);
        }

        .factory-text {
            flex: 1 1 42%;
            min-width: 260px;
            display: flex;
            flex-direction: column;
        }

        .factory-text h3 {
            font-weight: 400;
            margin-bottom: 12px;
        }

        .factory-text p {
            margin-bottom: 14px;
        }

        .factory-text ul {
            list-style: disc;
            padding-left: 20px;
            margin: 4px 0 10px;
        }

        .factory-text ul li {
            font-size: 16px;
            line-height: 1.7;
            margin-bottom: 2px;
        }
        .factory-text ul li:last-child {
            margin-bottom: 0;
        }

        .factory-gallery {
            flex: 1 1 48%;
            min-width: 280px;
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 12px;
        }

        .factory-gallery img {
            width: 100%;
            height: auto;
            aspect-ratio: 4 / 3;
            display: block;
            border-radius: var(--radius);
            background: var(--color-bg-img);
            object-fit: cover;
            transition: transform 0.3s ease;
        }

        .factory-gallery img:hover {
            transform: scale(1.02);
        }

        .qc-grid {
            display: flex;
            flex-wrap: wrap;
            gap: var(--gap-sm);
            margin-top: 4px;
            list-style: none;
            padding: 0;
        }

        .qc-item {
            flex: 1 1 180px;
            background: var(--color-white);
            border: 1px solid var(--color-card-border);
            border-radius: var(--radius);
            padding: 20px 18px;
            text-align: center;
            transition: box-shadow var(--transition), transform var(--transition);
        }

        .qc-item:hover {
            box-shadow: var(--shadow-card);
            transform: translateY(-2px);
        }

        .qc-item p {
            font-size: 16px;
            font-weight: 400;
            margin-bottom: 0;
            color: var(--color-heading);
        }

        .faq-list {
            display: flex;
            flex-direction: column;
            gap: 10px;
        }

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

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

        .faq-item summary {
            font-weight: 700;
            font-size: 16px;
            padding: 16px 20px;
            cursor: pointer;
            list-style: none;
            display: flex;
            align-items: center;
            justify-content: space-between;
            transition: background 0.15s ease;
            user-select: none;
            color: var(--color-heading);
        }

        .faq-item summary::-webkit-details-marker {
            display: none;
        }

        .faq-item summary::after {
            content: "\25B8";
            font-size: 20px;
            line-height: 1;
            color: var(--color-icon);
            transition: transform 0.25s ease;
            margin-left: 12px;
            flex-shrink: 0;
        }

        .faq-item[open] summary::after {
            transform: rotate(90deg);
        }

        .faq-item summary:hover {
            background: var(--color-bg-light);
        }

        .faq-item .faq-answer {
            padding: 0 20px 18px 20px;
            font-size: 16px;
            line-height: 1.7;
            color: var(--color-text);
        }

        .faq-item .faq-answer p {
            margin-bottom: 0;
        }

        @media (max-width: 992px) {
            .page-wrap {
                padding: 32px 20px 48px;
            }
            .structure-wrap,
            .factory-wrap {
                gap: var(--gap-md);
            }
            .factory-gallery {
                gap: 10px;
            }
            .app-grid {
                grid-template-columns: repeat(2, 1fr);
            }
        }

        @media (max-width: 768px) {
            .page-wrap {
                padding: 24px 16px 40px;
            }
            h2 {
                font-size: 24px;
                margin-bottom: 10px;
            }
            h3 {
                font-size: 18px;
            }
            .structure-wrap {
                flex-direction: column;
                gap: 24px;
            }
            .structure-text,
            .structure-image {
                flex: 1 1 auto;
                min-width: 0;
                width: 100%;
            }
            .structure-image img {
                max-width: 100%;
            }
            .factory-wrap {
                flex-direction: column;
                align-items: stretch;
                gap: 24px;
            }
            .factory-text {
                flex: 1 1 auto;
                min-width: 0;
                width: 100%;
            }
            .factory-gallery {
                flex: 1 1 auto;
                min-width: 0;
                width: 100%;
                gap: 8px;
            }
            .factory-gallery img {
                aspect-ratio: 4 / 3; /* consistent with desktop */
            }
            .app-grid {
                grid-template-columns: 1fr;
                gap: var(--gap-sm);
            }
            .spec-table-wrap {
                border-radius: var(--radius);
            }
            .spec-table td,
            .spec-table th {
                padding: 10px 14px;
                font-size: 15px;
            }
            .spec-table .label-cell {
                min-width: 100px;
                width: 28%;
            }
            .qc-item {
                flex: 1 1 140px;
            }
        }

        @media (max-width: 480px) {
            .page-wrap {
                padding: clamp(14px, 4vw, 18px) clamp(10px, 3vw, 12px) 32px;
            }
            h2 {
                font-size: 20px;
                margin-bottom: 8px;
            }
            h3 {
                font-size: 16px;
            }
            .spec-table td,
            .spec-table th {
                padding: 8px 10px;
                font-size: 14px;
            }
            .spec-table .label-cell {
                min-width: 80px;
                width: 26%;
            }
            .factory-gallery {
                gap: 6px;
            }
            .structure-wrap,
            .factory-wrap {
                gap: 18px;
            }
            .module {
                margin-bottom: 40px;
            }
            .faq-item summary {
                padding: 14px 16px;
                font-size: 15px;
            }
            .faq-item .faq-answer {
                padding: 0 16px 14px 16px;
                font-size: 15px;
            }
            .qc-item {
                flex: 1 1 100%;
                padding: 16px;
            }
            .app-card {
                padding: 16px 16px 14px;
            }
            .app-card .app-img {
                aspect-ratio: 16 / 9;
            }
        }