/* roulang page: index */
:root {
            --primary: #1E2D2B;
            --primary-light: #2A3E3B;
            --accent: #C49A6C;
            --accent-hover: #B08550;
            --bg: #F7F5F2;
            --white: #FFFFFF;
            --text-dark: #1A1A1A;
            --text-body: #4A4A4A;
            --text-muted: #7A7A7A;
            --border-light: #E5E2DD;
            --shadow-sm: 0 2px 8px rgba(0,0,0,0.04);
            --shadow-md: 0 8px 24px rgba(0,0,0,0.08);
            --radius-card: 12px;
            --radius-btn: 6px;
            --font-heading: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
            --font-body: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', sans-serif;
            --font-number: 'SF Mono', 'Roboto Mono', 'Menlo', monospace;
            --nav-height: 60px;
            --section-gap: 100px;
            --container-max: 1200px;
            transition: all 0.25s ease;
        }

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

        body {
            font-family: var(--font-body);
            background-color: var(--bg);
            color: var(--text-body);
            line-height: 1.7;
            font-size: 16px;
            -webkit-font-smoothing: antialiased;
        }

        h1, h2, h3, h4, .h1, .h2, .h3 {
            font-family: var(--font-heading);
            color: var(--text-dark);
            font-weight: 700;
            letter-spacing: -0.01em;
        }

        h1 {
            font-size: 42px;
            line-height: 1.2;
            margin-bottom: 16px;
        }

        h2 {
            font-size: 30px;
            margin-bottom: 12px;
        }

        h3 {
            font-size: 22px;
            margin-bottom: 8px;
        }

        a {
            color: var(--primary);
            text-decoration: none;
            transition: color 0.2s;
        }

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

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

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

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

        .bg-white {
            background-color: var(--white);
        }

        .bg-primary {
            background-color: var(--primary);
        }

        .text-white {
            color: #FFFFFF;
        }

        .text-accent {
            color: var(--accent);
        }

        .btn {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            padding: 0 28px;
            height: 48px;
            border-radius: var(--radius-btn);
            font-weight: 600;
            font-size: 16px;
            transition: all 0.25s ease;
            cursor: pointer;
            border: none;
            text-decoration: none;
            line-height: 1;
            background: transparent;
        }

        .btn-primary {
            background-color: var(--primary);
            color: white;
            border: 2px solid var(--primary);
        }

        .btn-primary:hover {
            background-color: #253936;
            border-color: #253936;
            color: white;
            transform: translateY(-2px);
            box-shadow: var(--shadow-md);
        }

        .btn-accent {
            background-color: var(--accent);
            color: white;
            border: 2px solid var(--accent);
        }

        .btn-accent:hover {
            background-color: var(--accent-hover);
            border-color: var(--accent-hover);
            color: white;
            transform: translateY(-2px);
            box-shadow: var(--shadow-md);
        }

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

        .btn-outline:hover {
            background-color: rgba(30,45,43,0.05);
            color: var(--primary);
            transform: translateY(-2px);
        }

        .btn-white-outline {
            background: transparent;
            border: 2px solid white;
            color: white;
        }

        .btn-white-outline:hover {
            background-color: rgba(255,255,255,0.15);
            color: white;
            transform: translateY(-2px);
        }

        /* 导航 */
        .site-header {
            position: fixed;
            top: 0;
            left: 0;
            width: 100%;
            height: var(--nav-height);
            background: rgba(255,255,255,0.96);
            backdrop-filter: blur(12px);
            border-bottom: 1px solid var(--border-light);
            z-index: 100;
            display: flex;
            align-items: center;
        }

        .nav-container {
            display: flex;
            justify-content: space-between;
            align-items: center;
            width: 100%;
            max-width: var(--container-max);
            margin: 0 auto;
            padding: 0 24px;
        }

        .logo {
            font-family: var(--font-heading);
            font-weight: 800;
            font-size: 22px;
            color: var(--primary);
            letter-spacing: -0.5px;
            display: flex;
            align-items: center;
            gap: 8px;
            text-decoration: none;
        }

        .logo i {
            color: var(--accent);
            font-size: 24px;
        }

        .nav-links {
            display: flex;
            gap: 28px;
            align-items: center;
        }

        .nav-links a {
            font-weight: 500;
            color: var(--text-body);
            position: relative;
            padding: 8px 0;
            font-size: 15px;
        }

        .nav-links a:after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            width: 0;
            height: 2px;
            background: var(--accent);
            transition: all 0.25s ease;
            transform: translateX(-50%);
        }

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

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

        .nav-cta {
            margin-left: 20px;
        }

        .menu-toggle {
            display: none;
            background: none;
            border: none;
            font-size: 26px;
            color: var(--text-dark);
            cursor: pointer;
        }

        @media (max-width: 768px) {
            .nav-links {
                display: none;
                position: absolute;
                top: var(--nav-height);
                left: 0;
                width: 100%;
                background: white;
                flex-direction: column;
                padding: 20px;
                box-shadow: var(--shadow-md);
                gap: 16px;
            }

            .nav-links.active {
                display: flex;
            }

            .menu-toggle {
                display: block;
            }

            .nav-cta.desktop {
                display: none;
            }
        }

        /* Hero 分屏 */
        .hero {
            display: flex;
            min-height: 100vh;
            padding-top: var(--nav-height);
            background: var(--bg);
        }

        .hero-content {
            flex: 1 1 50%;
            display: flex;
            align-items: center;
            padding: 60px 40px 60px 60px;
        }

        .hero-text {
            max-width: 560px;
        }

        .hero-text p {
            font-size: 18px;
            color: var(--text-body);
            margin-bottom: 32px;
            line-height: 1.8;
        }

        .hero-visual {
            flex: 1 1 50%;
            background-image: url('/assets/images/backpic/back-1.webp');
            background-size: cover;
            background-position: center;
            position: relative;
            min-height: 400px;
        }

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

        @media (max-width: 1024px) {
            .hero {
                flex-direction: column;
            }
            .hero-content {
                padding: 48px 24px;
                order: 2;
            }
            .hero-visual {
                height: 45vh;
                order: 1;
                min-height: 300px;
            }
            h1 {
                font-size: 36px;
            }
        }

        /* 卡片网格 */
        .card-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 30px;
        }

        .card {
            background: var(--white);
            border-radius: var(--radius-card);
            padding: 32px 24px;
            box-shadow: var(--shadow-sm);
            transition: all 0.3s ease;
            border: 1px solid transparent;
        }

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

        .card-icon {
            font-size: 32px;
            color: var(--accent);
            margin-bottom: 20px;
            display: inline-block;
            transition: transform 0.2s;
        }

        .card:hover .card-icon {
            transform: rotate(4deg) scale(1.05);
        }

        .card h3 {
            margin-bottom: 10px;
        }

        /* 优势数据 */
        .stats-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 40px;
            text-align: center;
        }

        .stat-number {
            font-family: var(--font-number);
            font-size: 50px;
            font-weight: 800;
            color: var(--primary);
            line-height: 1.1;
        }

        .stat-unit {
            font-size: 20px;
            font-weight: 600;
            color: var(--accent);
        }

        .stat-label {
            color: var(--text-muted);
            margin-top: 8px;
        }

        @media (max-width: 768px) {
            .stats-grid {
                grid-template-columns: repeat(2, 1fr);
                gap: 24px;
            }
            .card-grid {
                grid-template-columns: 1fr;
            }
        }

        /* 案例卡片 */
        .case-card {
            background: white;
            border-radius: var(--radius-card);
            overflow: hidden;
            box-shadow: var(--shadow-sm);
            transition: 0.3s;
        }

        .case-card:hover {
            transform: translateY(-8px);
            box-shadow: var(--shadow-md);
        }

        .case-img {
            height: 220px;
            overflow: hidden;
        }

        .case-img img {
            width: 100%;
            height: 100%;
            object-fit: cover;
            transition: transform 0.4s;
        }

        .case-card:hover .case-img img {
            transform: scale(1.04);
        }

        .case-info {
            padding: 24px;
        }

        .tag {
            display: inline-block;
            background: rgba(196,154,108,0.15);
            color: var(--accent);
            padding: 4px 12px;
            border-radius: 20px;
            font-size: 13px;
            font-weight: 600;
            margin-bottom: 10px;
        }

        /* FAQ */
        .accordion-item {
            border-bottom: 1px solid var(--border-light);
        }

        .accordion-title {
            background: none;
            border: none;
            width: 100%;
            text-align: left;
            padding: 18px 16px;
            font-weight: 600;
            font-size: 17px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            cursor: pointer;
            color: var(--text-dark);
            transition: 0.2s;
        }

        .accordion-title i {
            transition: transform 0.3s;
            color: var(--accent);
        }

        .accordion-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease;
            padding: 0 16px;
            color: var(--text-body);
        }

        .accordion-item.active .accordion-content {
            max-height: 200px;
            padding-bottom: 18px;
        }

        .accordion-item.active .accordion-title i {
            transform: rotate(180deg);
        }

        .footer {
            background: #2A2A2A;
            color: #B0B0B0;
            padding: 60px 0 20px;
        }

        .footer-grid {
            display: grid;
            grid-template-columns: 1.5fr 1fr 1fr 1fr;
            gap: 40px;
            margin-bottom: 40px;
        }

        .footer-logo {
            font-weight: 700;
            font-size: 20px;
            color: white;
            margin-bottom: 12px;
        }

        .footer a {
            color: #B0B0B0;
        }

        .footer a:hover {
            color: var(--accent);
        }

        .social-icons i {
            font-size: 20px;
            margin-right: 16px;
            color: #B0B0B0;
            transition: 0.2s;
        }

        .social-icons i:hover {
            color: var(--accent);
        }

        @media (max-width: 768px) {
            .footer-grid {
                grid-template-columns: 1fr 1fr;
            }
            .section {
                padding: 70px 0;
            }
        }

        .solution-steps {
            display: flex;
            justify-content: space-between;
            position: relative;
        }

        .step {
            text-align: center;
            flex: 1;
            position: relative;
        }

        .step-num {
            font-family: var(--font-number);
            font-size: 40px;
            color: rgba(30,45,43,0.2);
            font-weight: 700;
        }

        @media (max-width: 640px) {
            .solution-steps {
                flex-direction: column;
                gap: 30px;
            }
        }