/* roulang page: index */
:root {
            --primary-color: #4CAF50; /* 嫩草绿 */
            --secondary-color: #FFC107; /* 暖阳黄 */
            --background-color: #f8f9fa;
            --text-color: #343a40;
            --subtle-text-color: #6c757d;
            --border-color: #dee2e6;
            --card-bg: #ffffff;
            --footer-bg: #343a40;
            --footer-text-color: #ffffff;
            --radius-sm: 4px;
            --radius-md: 8px;
            --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
            --spacing-xs: 8px;
            --spacing-sm: 12px;
            --spacing-md: 16px;
            --spacing-lg: 24px;
            --spacing-xl: 32px;
        }

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            line-height: 1.6;
            color: var(--text-color);
            background-color: var(--background-color);
            margin: 0;
            padding: 0;
            box-sizing: border-box;
        }

        a {
            color: var(--primary-color);
            text-decoration: none;
            transition: color 0.3s ease;
        }

        a:hover {
            color: #367c39;
            text-decoration: underline;
        }

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

        .container {
            max-width: 1200px;
            margin: 0 auto;
            padding: 0 var(--spacing-md);
        }

        /* Header & Navigation */
        header {
            background-color: var(--card-bg);
            box-shadow: var(--shadow-md);
            padding: var(--spacing-md) 0;
        }

        nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: 1.8em;
            font-weight: bold;
            color: var(--primary-color);
            text-decoration: none;
        }
        .logo:hover {
            text-decoration: none;
        }

        .nav-links ul {
            list-style: none;
            margin: 0;
            padding: 0;
            display: flex;
            gap: var(--spacing-lg);
        }

        .nav-links a {
            font-weight: 500;
            color: var(--text-color);
            padding: var(--spacing-sm) var(--spacing-md);
            border-radius: var(--radius-sm);
            transition: background-color 0.3s ease, color 0.3s ease;
        }

        .nav-links a:hover,
        .nav-links a.active {
            background-color: var(--primary-color);
            color: #ffffff;
            text-decoration: none;
        }

        /* Hero Section */
        .hero {
            background-image: linear-gradient(rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)), url('/assets/images/backpic/back-1.webp');
            background-size: cover;
            background-position: center;
            color: #ffffff;
            text-align: center;
            padding: var(--spacing-xl) 0;
            position: relative;
        }

        .hero::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, 0.4);
            z-index: 1;
        }

        .hero-content {
            position: relative;
            z-index: 2;
            max-width: 800px;
            margin: 0 auto;
        }

        .hero h1 {
            font-size: 2.8em;
            margin-bottom: var(--spacing-sm);
            line-height: 1.2;
        }

        .hero p {
            font-size: 1.2em;
            margin-bottom: var(--spacing-lg);
            color: rgba(255, 255, 255, 0.9);
        }

        .cta-button {
            display: inline-block;
            background-color: var(--secondary-color);
            color: var(--text-color);
            padding: var(--spacing-sm) var(--spacing-lg);
            border-radius: var(--radius-md);
            font-weight: bold;
            font-size: 1.1em;
            transition: background-color 0.3s ease, transform 0.3s ease;
            box-shadow: var(--shadow-md);
        }

        .cta-button:hover {
            background-color: #e0a800;
            color: var(--text-color);
            text-decoration: none;
            transform: translateY(-2px);
        }

        /* Section Styles */
        .section {
            padding: var(--spacing-xl) 0;
        }

        .section h2 {
            text-align: center;
            font-size: 2.2em;
            margin-bottom: var(--spacing-lg);
            color: var(--text-color);
        }

        .section-description {
            text-align: center;
            max-width: 800px;
            margin: 0 auto var(--spacing-xl);
            font-size: 1.1em;
            color: var(--subtle-text-color);
        }

        /* Content List */
        .content-list {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: var(--spacing-lg);
        }

        .content-card {
            background-color: var(--card-bg);
            border-radius: var(--radius-md);
            box-shadow: var(--shadow-md);
            overflow: hidden;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            display: flex;
            flex-direction: column;
        }

        .content-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
        }

        .content-card img {
            width: 100%;
            height: 200px; /* Fixed height for images */
            object-fit: cover;
        }

        .card-content {
            padding: var(--spacing-md);
            flex-grow: 1;
            display: flex;
            flex-direction: column;
        }

        .card-title {
            font-size: 1.4em;
            font-weight: bold;
            margin-bottom: var(--spacing-sm);
            flex-grow: 1;
        }

        .card-meta {
            font-size: 0.9em;
            color: var(--subtle-text-color);
            margin-bottom: var(--spacing-sm);
            display: flex;
            justify-content: space-between;
        }

        .card-excerpt {
            font-size: 1em;
            color: var(--subtle-text-color);
            margin-bottom: var(--spacing-md);
            display: -webkit-box;
            -webkit-line-clamp: 3;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        .card-link {
            display: inline-block;
            font-weight: 500;
            margin-top: auto; /* Pushes the link to the bottom */
        }

        /* FAQ Section */
        .faq-section {
            background-color: var(--card-bg);
            border-radius: var(--radius-md);
            padding: var(--spacing-lg);
            box-shadow: var(--shadow-md);
        }

        .faq-item {
            border-bottom: 1px solid var(--border-color);
            padding: var(--spacing-md) 0;
        }

        .faq-item:last-child {
            border-bottom: none;
        }

        .faq-question {
            font-weight: bold;
            font-size: 1.2em;
            cursor: pointer;
            position: relative;
            padding-left: 25px; /* Space for icon */
        }

        .faq-question::before {
            content: '+';
            position: absolute;
            left: 0;
            top: 0;
            font-size: 1.2em;
            color: var(--primary-color);
            transition: transform 0.3s ease;
        }

        .faq-item.active .faq-question::before {
            transform: rotate(45deg);
        }

        .faq-answer {
            font-size: 1em;
            color: var(--subtle-text-color);
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s ease, padding 0.3s ease;
            padding: 0;
        }

        .faq-item.active .faq-answer {
            max-height: 200px; /* Adjust as needed */
            padding: var(--spacing-sm) 0;
        }

        /* CTA Section */
        .cta-section {
            background-color: var(--primary-color);
            color: #ffffff;
            text-align: center;
            padding: var(--spacing-xl) 0;
            background-image: linear-gradient(rgba(0, 0, 0, 0.2), rgba(0, 0, 0, 0.2)), url('/assets/images/backpic/back-2.webp');
            background-size: cover;
            background-position: center;
        }

        .cta-section h2 {
            color: #ffffff;
            font-size: 2.5em;
            margin-bottom: var(--spacing-md);
        }

        .cta-section p {
            font-size: 1.2em;
            margin-bottom: var(--spacing-lg);
            opacity: 0.9;
        }

        .cta-button.secondary {
            background-color: var(--secondary-color);
            color: var(--text-color);
        }

        .cta-button.secondary:hover {
            background-color: #e0a800;
        }

        /* Footer */
        footer {
            background-color: var(--footer-bg);
            color: var(--footer-text-color);
            padding: var(--spacing-lg) 0;
            text-align: center;
            font-size: 0.9em;
        }

        .footer-logo {
            font-size: 1.8em;
            font-weight: bold;
            color: var(--secondary-color);
            margin-bottom: var(--spacing-md);
            text-decoration: none;
        }

        .footer-links {
            margin-bottom: var(--spacing-md);
            display: flex;
            justify-content: center;
            gap: var(--spacing-lg);
            flex-wrap: wrap;
        }

        .footer-links a {
            color: var(--footer-text-color);
            opacity: 0.8;
            transition: opacity 0.3s ease;
        }

        .footer-links a:hover {
            opacity: 1;
            text-decoration: underline;
        }

        .copyright {
            opacity: 0.7;
        }

        /* Mobile Responsiveness */
        @media (max-width: 768px) {
            nav {
                flex-direction: column;
                align-items: flex-start;
            }

            .logo {
                margin-bottom: var(--spacing-md);
            }

            .nav-links ul {
                flex-direction: column;
                width: 100%;
                gap: 0;
            }

            .nav-links li {
                border-bottom: 1px solid var(--border-color);
            }

            .nav-links a {
                display: block;
                padding: var(--spacing-md) 0;
                width: 100%;
            }

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

            .hero p {
                font-size: 1em;
            }

            .section h2 {
                font-size: 1.8em;
            }

            .content-list {
                grid-template-columns: 1fr;
            }

            .footer-links {
                flex-direction: column;
                gap: var(--spacing-sm);
            }
        }

/* roulang page: article */
body{font-family:"Microsoft YaHei",system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;line-height:1.7;color:#1f2937;background:#f7f9fc}
  header,footer{background:#0f172a;color:#fff} header a,footer a{color:inherit;text-decoration:none}
  main section{padding:64px 0} .container{max-width:1180px}
  .hero,.site-hero{background:linear-gradient(135deg,#0f172a,#1d4ed8);color:#fff}
  .card,.feature-card,.service-card,.category-card{border:1px solid rgba(15,23,42,.08);box-shadow:0 12px 32px rgba(15,23,42,.08);border-radius:16px}
  .btn,.button,a[class*="btn"]{border-radius:999px;font-weight:700}
  img{max-width:100%;height:auto} @media(max-width:768px){main section{padding:42px 0} h1{font-size:2rem}}

/* roulang page: category1 */
:root {
            --primary-color: #007bff;
            --secondary-color: #6c757d;
            --background-color: #f8f9fa;
            --text-color: #343a40;
            --light-text-color: #6c757d;
            --border-color: #dee2e6;
            --card-background: #ffffff;
            --footer-background: #343a40;
            --footer-text-color: #ffffff;
            --header-background: #ffffff;
            --container-max-width: 1200px;
            --spacing-xs: 8px;
            --spacing-sm: 16px;
            --spacing-md: 24px;
            --spacing-lg: 32px;
            --spacing-xl: 48px;
            --border-radius: 5px;
            --box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
            --transition-speed: 0.3s;
        }

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

        body {
            font-family: 'Helvetica Neue', Arial, sans-serif;
            line-height: 1.6;
            color: var(--text-color);
            background-color: var(--background-color);
            scroll-behavior: smooth;
        }

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

        a {
            color: var(--primary-color);
            text-decoration: none;
            transition: color var(--transition-speed) ease;
        }

        a:hover {
            color: #0056b3;
        }

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

        button, input[type="submit"] {
            background-color: var(--primary-color);
            color: white;
            border: none;
            padding: var(--spacing-sm) var(--spacing-md);
            border-radius: var(--border-radius);
            cursor: pointer;
            transition: background-color var(--transition-speed) ease, transform var(--transition-speed) ease;
            font-size: 1rem;
        }

        button:hover, input[type="submit"]:hover {
            background-color: #0056b3;
            transform: translateY(-2px);
        }

        button:active, input[type="submit"]:active {
            transform: translateY(0);
        }

        /* Header */
        header {
            background-color: var(--header-background);
            padding: var(--spacing-sm) 0;
            box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
            position: sticky;
            top: 0;
            z-index: 1000;
        }

        header .container {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: 1.8rem;
            font-weight: bold;
            color: var(--text-color);
        }
        .logo:hover {
            color: var(--primary-color);
        }

        nav ul {
            list-style: none;
            display: flex;
        }

        nav ul li {
            margin-left: var(--spacing-md);
        }

        nav ul li a {
            color: var(--light-text-color);
            font-weight: 500;
            padding: var(--spacing-sm) 0;
            transition: color var(--transition-speed) ease;
            position: relative;
        }

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

        nav ul li a.active::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 100%;
            height: 2px;
            background-color: var(--primary-color);
        }

        /* Hero Section */
        .hero {
            background-image: url('/assets/images/backpic/back-2.webp');
            background-size: cover;
            background-position: center;
            color: white;
            padding: var(--spacing-xl) 0;
            text-align: center;
            position: relative;
        }

        .hero::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background: rgba(0, 0, 0, 0.5);
            z-index: 1;
        }

        .hero .container {
            position: relative;
            z-index: 2;
        }

        .hero h1 {
            font-size: 3rem;
            margin-bottom: var(--spacing-md);
        }

        .hero p {
            font-size: 1.2rem;
            max-width: 800px;
            margin: 0 auto var(--spacing-lg);
        }

        /* Section Styles */
        section {
            padding: var(--spacing-xl) 0;
        }

        .section-title {
            text-align: center;
            font-size: 2.5rem;
            margin-bottom: var(--spacing-lg);
            color: var(--text-color);
        }

        .section-subtitle {
            text-align: center;
            font-size: 1.2rem;
            color: var(--light-text-color);
            margin-bottom: var(--spacing-xl);
        }

        /* Card Styles */
        .card {
            background-color: var(--card-background);
            border-radius: var(--border-radius);
            box-shadow: var(--box-shadow);
            transition: transform var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
            overflow: hidden;
            display: flex;
            flex-direction: column;
        }

        .card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
        }

        .card img {
            width: 100%;
            height: 200px; /* Fixed height for consistency */
            object-fit: cover; /* Ensure image covers the area */
        }

        .card-content {
            padding: var(--spacing-md);
            flex-grow: 1;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .card-title {
            font-size: 1.4rem;
            margin-bottom: var(--spacing-sm);
            color: var(--text-color);
        }

        .card-text {
            font-size: 0.95rem;
            color: var(--light-text-color);
            margin-bottom: var(--spacing-md);
        }

        .card-link {
            font-weight: 500;
            display: inline-block;
            margin-top: auto; /* Pushes the link to the bottom */
        }

        .card-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: var(--spacing-lg);
        }

        /* Featured Content */
        .featured-content .card-grid {
            grid-template-columns: repeat(2, 1fr);
        }

        .featured-content .card-title {
            font-size: 1.6rem;
        }

        /* Process Section */
        .process-section .container {
            text-align: center;
        }

        .process-steps {
            display: flex;
            justify-content: space-around;
            margin-top: var(--spacing-xl);
            flex-wrap: wrap;
            gap: var(--spacing-lg);
        }

        .process-step {
            max-width: 300px;
        }

        .process-step-icon {
            font-size: 3rem;
            color: var(--primary-color);
            margin-bottom: var(--spacing-sm);
        }

        .process-step-title {
            font-size: 1.3rem;
            font-weight: bold;
            margin-bottom: var(--spacing-sm);
        }

        .process-step-description {
            font-size: 0.95rem;
            color: var(--light-text-color);
        }

        /* FAQ Section */
        .faq-section .container {
            max-width: 800px;
        }

        .faq-item {
            margin-bottom: var(--spacing-sm);
            border: 1px solid var(--border-color);
            border-radius: var(--border-radius);
        }

        .faq-question {
            background-color: var(--card-background);
            padding: var(--spacing-md);
            cursor: pointer;
            font-weight: bold;
            display: flex;
            justify-content: space-between;
            align-items: center;
            transition: background-color var(--transition-speed) ease;
        }

        .faq-question:hover {
            background-color: #f0f0f0;
        }

        .faq-question::after {
            content: '+';
            font-size: 1.5rem;
            transition: transform var(--transition-speed) ease;
        }

        .faq-item.active .faq-question::after {
            transform: rotate(45deg);
        }

        .faq-answer {
            background-color: var(--background-color);
            padding: var(--spacing-md);
            max-height: 0;
            overflow: hidden;
            transition: max-height var(--transition-speed) ease-out, padding var(--transition-speed) ease-out;
        }

        .faq-item.active .faq-answer {
            max-height: 200px; /* Adjust as needed */
            padding: var(--spacing-md);
        }

        /* CTA Section */
        .cta-section {
            background-color: var(--primary-color);
            color: white;
            text-align: center;
            padding: var(--spacing-xl) 0;
        }

        .cta-section h2 {
            font-size: 2.5rem;
            margin-bottom: var(--spacing-md);
        }

        .cta-section p {
            font-size: 1.1rem;
            margin-bottom: var(--spacing-lg);
        }

        .cta-section button {
            background-color: white;
            color: var(--primary-color);
            font-size: 1.1rem;
            padding: var(--spacing-sm) var(--spacing-lg);
        }

        .cta-section button:hover {
            background-color: #e0e0e0;
        }

        /* Footer */
        footer {
            background-color: var(--footer-background);
            color: var(--footer-text-color);
            padding: var(--spacing-xl) 0;
            text-align: center;
        }

        .footer-logo {
            font-size: 1.8rem;
            font-weight: bold;
            color: var(--footer-text-color);
            margin-bottom: var(--spacing-md);
            display: block;
        }

        .footer-links {
            margin-bottom: var(--spacing-lg);
        }

        .footer-links a {
            color: var(--footer-text-color);
            margin: 0 var(--spacing-sm);
            transition: color var(--transition-speed) ease;
        }

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

        .copyright {
            font-size: 0.9rem;
            opacity: 0.8;
        }

        /* Responsive Adjustments */
        @media (max-width: 992px) {
            .card-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .hero h1 {
                font-size: 2.5rem;
            }
            .hero p {
                font-size: 1.1rem;
            }
            .section-title {
                font-size: 2rem;
            }
        }

        @media (max-width: 768px) {
            nav ul {
                flex-direction: column;
                align-items: center;
                width: 100%;
                display: none; /* Hidden by default, shown by JS toggle */
            }
            nav ul li {
                margin: var(--spacing-sm) 0;
            }
            .nav-links {
                display: flex;
                flex-direction: column;
                align-items: center;
                width: 100%;
            }
            .nav-links ul {
                display: none; /* Hidden by default */
                flex-direction: column;
                width: 100%;
                text-align: center;
            }
            .nav-links ul.active {
                display: flex; /* Shown when toggled */
            }
            .menu-toggle {
                display: block;
                font-size: 1.8rem;
                cursor: pointer;
                color: var(--text-color);
            }
            .hero h1 {
                font-size: 2rem;
            }
            .card-grid {
                grid-template-columns: 1fr;
            }
            .process-steps {
                flex-direction: column;
                align-items: center;
            }
            .footer-links {
                display: flex;
                flex-direction: column;
            }
            .footer-links a {
                margin: var(--spacing-xs) 0;
            }
        }

        @media (max-width: 576px) {
            .hero h1 {
                font-size: 1.8rem;
            }
            .hero p {
                font-size: 1rem;
            }
            .section-title {
                font-size: 1.8rem;
            }
            .cta-section h2 {
                font-size: 2rem;
            }
            button, input[type="submit"] {
                padding: var(--spacing-sm) var(--spacing-md);
                font-size: 0.9rem;
            }
        }

        /* Menu Toggle Button (for mobile) */
        .menu-toggle {
            display: none;
            font-size: 2rem;
            cursor: pointer;
            color: var(--text-color);
        }

/* roulang page: category2 */
:root {
            --primary-color: #FF6F61;
            --secondary-color: #4CAF50;
            --accent-color: #FFD700;
            --background-color: #f8f9fa;
            --text-color: #333;
            --light-text-color: #666;
            --border-color: #ddd;
            --card-background: #fff;
            --container-max-width: 1200px;
            --spacing-unit: 1rem;
            --borderRadius: 8px;
            --boxShadow: 0 4px 12px rgba(0, 0, 0, 0.05);
            --transition: all 0.3s ease;
        }

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

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            line-height: 1.6;
            color: var(--text-color);
            background-color: var(--background-color);
        }

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

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

        a:hover {
            color: #e65a50;
            text-decoration: underline;
        }

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

        button {
            display: inline-block;
            padding: 0.8rem 1.5rem;
            background-color: var(--primary-color);
            color: #fff;
            border: none;
            border-radius: var(--borderRadius);
            cursor: pointer;
            font-size: 1rem;
            transition: var(--transition);
        }

        button:hover {
            background-color: #e65a50;
            transform: translateY(-2px);
            box-shadow: var(--boxShadow);
        }

        header {
            background-color: var(--card-background);
            box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
            padding: var(--spacing-unit) 0;
        }

        nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: 1.8rem;
            font-weight: bold;
            color: var(--primary-color);
            text-decoration: none;
        }

        .logo:hover {
            text-decoration: none;
        }

        .nav-links ul {
            list-style: none;
            display: flex;
        }

        .nav-links li {
            margin-left: calc(var(--spacing-unit) * 2);
        }

        .nav-links a {
            color: var(--text-color);
            font-weight: 500;
            padding: 0.5rem 0;
            position: relative;
        }

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

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

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

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

        .hero {
            background-image: linear-gradient(rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)), url('/assets/images/backpic/back-3.webp');
            background-size: cover;
            background-position: center;
            color: #fff;
            text-align: center;
            padding: calc(var(--spacing-unit) * 6) 0;
            margin-bottom: calc(var(--spacing-unit) * 4);
            position: relative;
            overflow: hidden;
        }

        .hero::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(0,0,0,0.4);
            z-index: 1;
        }

        .hero-content {
            position: relative;
            z-index: 2;
        }

        .hero h1 {
            font-size: 3rem;
            margin-bottom: var(--spacing-unit);
            line-height: 1.2;
        }

        .hero p {
            font-size: 1.2rem;
            margin-bottom: calc(var(--spacing-unit) * 2);
            max-width: 800px;
            margin-left: auto;
            margin-right: auto;
        }

        .main-content {
            padding: var(--spacing-unit) 0;
        }

        .section {
            margin-bottom: calc(var(--spacing-unit) * 4);
        }

        .section-title {
            font-size: 2rem;
            text-align: center;
            margin-bottom: calc(var(--spacing-unit) * 3);
            position: relative;
            padding-bottom: calc(var(--spacing-unit) * 1.5);
        }

        .section-title::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            width: 60px;
            height: 3px;
            background-color: var(--primary-color);
            border-radius: 2px;
        }

        .feature-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: calc(var(--spacing-unit) * 2);
        }

        .feature-card {
            background-color: var(--card-background);
            border-radius: var(--borderRadius);
            box-shadow: var(--boxShadow);
            padding: calc(var(--spacing-unit) * 2);
            text-align: center;
            transition: var(--transition);
        }

        .feature-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.1);
        }

        .feature-card img {
            width: 60px;
            height: 60px;
            margin: 0 auto calc(var(--spacing-unit) * 1.5);
        }

        .feature-card h3 {
            font-size: 1.4rem;
            margin-bottom: var(--spacing-unit);
            color: var(--primary-color);
        }

        .feature-card p {
            font-size: 0.95rem;
            color: var(--light-text-color);
        }

        .content-block {
            display: flex;
            align-items: center;
            gap: calc(var(--spacing-unit) * 3);
            margin-bottom: calc(var(--spacing-unit) * 4);
            flex-wrap: wrap;
        }

        .content-block.reverse {
            flex-direction: row-reverse;
        }

        .content-block div {
            flex: 1;
            min-width: 300px;
        }

        .content-block h2 {
            font-size: 2.2rem;
            margin-bottom: var(--spacing-unit);
            line-height: 1.3;
        }

        .content-block p {
            font-size: 1rem;
            color: var(--light-text-color);
            margin-bottom: var(--spacing-unit);
        }

        .content-block ul {
            list-style: none;
            padding-left: 0;
        }

        .content-block li {
            margin-bottom: calc(var(--spacing-unit) * 0.8);
            display: flex;
            align-items: center;
            color: var(--light-text-color);
        }

        .content-block li::before {
            content: '✔';
            color: var(--secondary-color);
            margin-right: var(--spacing-unit);
            font-weight: bold;
        }

        .content-block img {
            border-radius: var(--borderRadius);
            box-shadow: var(--boxShadow);
        }

        .cta-section {
            background-color: var(--primary-color);
            color: #fff;
            text-align: center;
            padding: calc(var(--spacing-unit) * 5) 0;
            border-radius: var(--borderRadius);
        }

        .cta-section h2 {
            font-size: 2.5rem;
            margin-bottom: var(--spacing-unit);
        }

        .cta-section p {
            font-size: 1.1rem;
            margin-bottom: calc(var(--spacing-unit) * 3);
            opacity: 0.9;
        }

        .cta-section button {
            background-color: var(--accent-color);
            color: var(--text-color);
            font-weight: bold;
            padding: 1rem 2rem;
            font-size: 1.1rem;
        }

        .cta-section button:hover {
            background-color: #e6c300;
        }

        .faq-section {
            background-color: var(--card-background);
            padding: calc(var(--spacing-unit) * 3) 0;
            border-radius: var(--borderRadius);
            box-shadow: var(--boxShadow);
        }

        .faq-item {
            margin-bottom: var(--spacing-unit);
        }

        .faq-question {
            font-size: 1.2rem;
            font-weight: bold;
            cursor: pointer;
            padding: var(--spacing-unit);
            background-color: #f1f1f1;
            border-radius: var(--borderRadius) var(--borderRadius) 0 0;
            transition: var(--transition);
            position: relative;
        }

        .faq-question::after {
            content: '+';
            position: absolute;
            right: var(--spacing-unit);
            font-size: 1.5rem;
            transition: var(--transition);
        }

        .faq-question.open::after {
            content: '−';
        }

        .faq-answer {
            max-height: 0;
            overflow: hidden;
            padding: 0 var(--spacing-unit);
            transition: max-height 0.3s ease-out, padding 0.3s ease-out;
            background-color: var(--card-background);
            border-radius: 0 0 var(--borderRadius) var(--borderRadius);
        }

        .faq-answer p {
            padding: var(--spacing-unit) 0;
            color: var(--light-text-color);
        }

        footer {
            background-color: #2c3e50;
            color: #ecf0f1;
            padding: calc(var(--spacing-unit) * 3) 0;
            margin-top: calc(var(--spacing-unit) * 5);
            text-align: center;
        }

        .footer-logo {
            font-size: 1.8rem;
            font-weight: bold;
            color: #fff;
            margin-bottom: var(--spacing-unit);
            display: block;
            text-decoration: none;
        }

        .footer-links {
            margin-bottom: calc(var(--spacing-unit) * 2);
        }

        .footer-links a {
            color: #bdc3c7;
            margin: 0 var(--spacing-unit);
            text-decoration: none;
        }

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

        .copyright {
            font-size: 0.9rem;
            color: #7f8c8d;
        }

        /* Responsive Styles */
        @media (max-width: 768px) {
            nav {
                flex-direction: column;
            }

            .logo {
                margin-bottom: var(--spacing-unit);
            }

            .nav-links ul {
                flex-direction: column;
                align-items: center;
                margin-top: var(--spacing-unit);
            }

            .nav-links li {
                margin: 0.5rem 0;
            }

            .hero h1 {
                font-size: 2.5rem;
            }

            .hero p {
                font-size: 1rem;
            }

            .content-block {
                flex-direction: column;
            }

            .content-block.reverse {
                flex-direction: column;
            }

            .content-block div {
                min-width: unset;
                width: 100%;
            }

            .content-block img {
                margin-top: var(--spacing-unit);
            }

            .section-title {
                font-size: 1.8rem;
            }

            .cta-section h2 {
                font-size: 2rem;
            }

            .cta-section p {
                font-size: 1rem;
                margin-bottom: var(--spacing-unit);
            }

            .cta-section button {
                padding: 0.8rem 1.5rem;
            }
        }

        @media (max-width: 520px) {
            .logo {
                font-size: 1.5rem;
            }

            .hero h1 {
                font-size: 2rem;
            }

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

/* roulang page: category3 */
:root {
            --primary-color: #4CAF50;
            --secondary-color: #FFC107;
            --background-color: #f4f7f6;
            --text-color: #333;
            --light-text-color: #666;
            --border-color: #e0e0e0;
            --card-background: #fff;
            --footer-background: #333;
            --footer-text-color: #fff;
            --button-hover-bg: #45a049;
            --button-hover-text: #fff;
            --container-max-width: 1200px;
            --spacing-unit: 16px;
            --border-radius: 8px;
            --shadow: 0 4px 8px rgba(0,0,0,0.1);
            --card-shadow: 0 2px 4px rgba(0,0,0,0.05);
            --transition-speed: 0.3s;
        }

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

        html {
            font-size: 16px;
            line-height: 1.6;
        }

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            background-color: var(--background-color);
            color: var(--text-color);
            display: flex;
            flex-direction: column;
            min-height: 100vh;
        }

        .container {
            width: 90%;
            max-width: var(--container-max-width);
            margin: 0 auto;
            padding: 0 var(--spacing-unit);
        }

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

        a:hover {
            color: var(--button-hover-bg);
        }

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

        h1, h2, h3, h4, h5, h6 {
            margin-bottom: calc(var(--spacing-unit) * 0.8);
            line-height: 1.3;
        }

        h1 { font-size: 2.5rem; }
        h2 { font-size: 2rem; }
        h3 { font-size: 1.75rem; }
        h4 { font-size: 1.5rem; }
        h5 { font-size: 1.25rem; }
        h6 { font-size: 1rem; }

        p {
            margin-bottom: var(--spacing-unit);
        }

        .btn {
            display: inline-block;
            padding: calc(var(--spacing-unit) * 0.7) calc(var(--spacing-unit) * 1.5);
            background-color: var(--primary-color);
            color: var(--button-hover-text);
            border: none;
            border-radius: var(--border-radius);
            cursor: pointer;
            font-size: 1rem;
            transition: background-color var(--transition-speed), transform var(--transition-speed);
            text-align: center;
        }

        .btn:hover {
            background-color: var(--button-hover-bg);
            transform: translateY(-2px);
        }

        .btn-secondary {
            background-color: var(--secondary-color);
            color: var(--text-color);
        }

        .btn-secondary:hover {
            background-color: #e0a800;
        }

        /* Header and Navigation */
        header {
            background-color: var(--card-background);
            box-shadow: var(--card-shadow);
            padding: calc(var(--spacing-unit) * 0.8) 0;
            position: sticky;
            top: 0;
            z-index: 1000;
        }

        nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: 1.8rem;
            font-weight: bold;
            color: var(--primary-color);
            letter-spacing: 1px;
        }

        .nav-links ul {
            list-style: none;
            display: flex;
            gap: calc(var(--spacing-unit) * 1.5);
        }

        .nav-links a {
            color: var(--text-color);
            font-weight: 500;
            padding: var(--spacing-unit) 0;
            position: relative;
            transition: color var(--transition-speed);
        }

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

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

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

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

        /* Hero Section */
        .hero {
            background-color: var(--card-background);
            background-image: url('/assets/images/backpic/back-3.webp');
            background-size: cover;
            background-position: center;
            color: var(--footer-text-color);
            text-align: center;
            padding: calc(var(--spacing-unit) * 5) calc(var(--spacing-unit) * 2);
            position: relative;
            display: flex;
            align-items: center;
            justify-content: center;
            min-height: 50vh;
            margin-bottom: calc(var(--spacing-unit) * 2);
        }

        .hero::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background-color: rgba(0, 0, 0, 0.6);
            z-index: 1;
        }

        .hero .hero-content {
            position: relative;
            z-index: 2;
            max-width: 800px;
        }

        .hero h1 {
            font-size: 3rem;
            margin-bottom: var(--spacing-unit);
            color: #fff;
        }

        .hero p {
            font-size: 1.2rem;
            color: #e0e0e0;
            margin-bottom: calc(var(--spacing-unit) * 2);
        }

        /* Section Styles */
        .section {
            padding: calc(var(--spacing-unit) * 3) 0;
        }

        .section h2 {
            text-align: center;
            margin-bottom: calc(var(--spacing-unit) * 2);
            color: var(--text-color);
            font-size: 2.2rem;
        }

        .section-content {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: calc(var(--spacing-unit) * 2);
        }

        .card {
            background-color: var(--card-background);
            border-radius: var(--border-radius);
            box-shadow: var(--card-shadow);
            overflow: hidden;
            transition: transform var(--transition-speed), box-shadow var(--transition-speed);
            display: flex;
            flex-direction: column;
        }

        .card:hover {
            transform: translateY(-5px);
            box-shadow: var(--shadow);
        }

        .card img {
            width: 100%;
            height: 200px;
            object-fit: cover;
        }

        .card-body {
            padding: var(--spacing-unit);
            flex-grow: 1;
            display: flex;
            flex-direction: column;
        }

        .card-body h3 {
            font-size: 1.4rem;
            margin-bottom: calc(var(--spacing-unit) * 0.7);
            color: var(--text-color);
        }

        .card-body p {
            font-size: 0.95rem;
            color: var(--light-text-color);
            flex-grow: 1;
            margin-bottom: var(--spacing-unit);
        }

        .card-footer {
            padding: var(--spacing-unit);
            text-align: right;
            border-top: 1px solid var(--border-color);
        }

        .card-footer .btn {
            padding: calc(var(--spacing-unit) * 0.5) calc(var(--spacing-unit) * 1);
            font-size: 0.9rem;
        }

        .card-badge {
            display: inline-block;
            background-color: var(--secondary-color);
            color: var(--text-color);
            padding: 4px 10px;
            border-radius: 4px;
            font-size: 0.8rem;
            margin-bottom: calc(var(--spacing-unit) * 0.7);
        }

        /* FAQ Section */
        .faq-section {
            background-color: var(--card-background);
            padding: calc(var(--spacing-unit) * 3) 0;
            margin-top: calc(var(--spacing-unit) * 2);
            box-shadow: var(--card-shadow);
            border-radius: var(--border-radius);
        }
        .faq-section .container {
            text-align: center;
        }

        .faq-item {
            margin-bottom: var(--spacing-unit);
            border-bottom: 1px solid var(--border-color);
            padding-bottom: var(--spacing-unit);
            text-align: left;
        }
        .faq-item:last-child {
            border-bottom: none;
            padding-bottom: 0;
        }

        .faq-question {
            font-weight: bold;
            cursor: pointer;
            position: relative;
            padding-left: calc(var(--spacing-unit) * 2);
            font-size: 1.1rem;
        }

        .faq-question::before,
        .faq-question::after {
            content: '';
            position: absolute;
            top: 50%;
            right: var(--spacing-unit);
            width: 15px;
            height: 2px;
            background-color: var(--text-color);
            transition: transform var(--transition-speed);
        }

        .faq-question::after {
            transform: rotate(90deg);
        }

        .faq-item.active .faq-question::after {
            transform: rotate(180deg);
        }
        .faq-item.active .faq-question::before {
             transform: rotate(0deg);
        }


        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height var(--transition-speed) ease-out;
            padding-left: var(--spacing-unit);
            font-size: 0.95rem;
            color: var(--light-text-color);
            margin-top: var(--spacing-unit);
        }

        .faq-item.active .faq-answer {
            max-height: 200px; /* Adjust as needed */
        }

        /* CTA Section */
        .cta-section {
            background-color: var(--primary-color);
            color: var(--footer-text-color);
            text-align: center;
            padding: calc(var(--spacing-unit) * 4) 0;
            margin-top: calc(var(--spacing-unit) * 3);
        }

        .cta-section h2 {
            font-size: 2.5rem;
            margin-bottom: var(--spacing-unit);
            color: #fff;
        }

        .cta-section p {
            font-size: 1.2rem;
            margin-bottom: calc(var(--spacing-unit) * 2);
        }

        .cta-section .btn {
            background-color: var(--secondary-color);
            color: var(--text-color);
            font-size: 1.1rem;
            padding: calc(var(--spacing-unit) * 1) calc(var(--spacing-unit) * 2);
        }

        .cta-section .btn:hover {
            background-color: #e0a800;
        }

        /* Footer */
        footer {
            background-color: var(--footer-background);
            color: var(--footer-text-color);
            padding: calc(var(--spacing-unit) * 2.5) 0;
            margin-top: auto; /* Push footer to bottom */
        }

        footer .container {
            display: flex;
            flex-direction: column;
            align-items: center;
            text-align: center;
        }

        .footer-logo {
            font-size: 1.8rem;
            font-weight: bold;
            color: #fff;
            margin-bottom: var(--spacing-unit);
        }

        .footer-links {
            margin-bottom: calc(var(--spacing-unit) * 1.5);
            display: flex;
            gap: calc(var(--spacing-unit) * 1.5);
            flex-wrap: wrap;
            justify-content: center;
        }

        .footer-links a {
            color: var(--footer-text-color);
            font-weight: 500;
            transition: color var(--transition-speed);
        }

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

        .copyright {
            font-size: 0.9rem;
            color: rgba(255, 255, 255, 0.7);
        }

        /* Responsive Design */
        @media (max-width: 1024px) {
            .section-content {
                grid-template-columns: repeat(2, 1fr);
            }
            .nav-links ul {
                gap: calc(var(--spacing-unit) * 1);
            }
            .logo {
                font-size: 1.5rem;
            }
        }

        @media (max-width: 768px) {
            h1 { font-size: 2rem; }
            h2 { font-size: 1.75rem; }

            .hero {
                padding: calc(var(--spacing-unit) * 4) calc(var(--spacing-unit) * 1);
                min-height: 40vh;
            }
            .hero h1 {
                font-size: 2.5rem;
            }
            .hero p {
                font-size: 1rem;
            }

            .section-content {
                grid-template-columns: 1fr;
            }

            nav {
                flex-wrap: wrap;
                justify-content: center;
            }
            .nav-links {
                width: 100%;
                justify-content: center;
                margin-top: var(--spacing-unit);
            }
            .nav-links ul {
                flex-direction: column;
                align-items: center;
                gap: var(--spacing-unit);
            }
            .nav-links a {
                padding: var(--spacing-unit) 0;
            }

            .footer-links {
                flex-direction: column;
                gap: var(--spacing-unit);
            }
        }

        @media (max-width: 520px) {
             .logo {
                font-size: 1.3rem;
            }
            .hero h1 {
                font-size: 2rem;
            }
            .cta-section h2 {
                font-size: 2rem;
            }
            .cta-section p {
                font-size: 1rem;
            }
        }

/* roulang page: category4 */
/* CSS 变量定义 */
        :root {
            --primary-color: #FF6B6B; /* 主色调，活力、吸引 */
            --secondary-color: #4ECDC4; /* 辅助色调，清新、技术感 */
            --tertiary-color: #45B7D1; /* 强调色，专业、信息 */
            --background-color: #F8F9FA; /* 页面背景 */
            --card-background: #FFFFFF; /* 卡片背景 */
            --text-color: #333333; /* 主要文字颜色 */
            --light-text-color: #666666; /* 次要文字颜色 */
            --border-color: #E0E0E0; /* 分隔线/边框颜色 */
            --hover-shadow: rgba(0, 0, 0, 0.1); /* hover 阴影 */
            --card-shadow: 0 4px 15px rgba(0, 0, 0, 0.08); /* 卡片阴影 */
            --container-max-width: 1200px; /* 内容最大宽度 */
            --spacing-unit: 1rem; /* 基本间距单位 */
            --radius-small: 4px; /* 小圆角 */
            --radius-medium: 8px; /* 中等圆角 */
            --radius-large: 16px; /* 大圆角 */
            --transition-speed: 0.3s; /* 过渡动画速度 */
        }

        /* 基础 Reset & Base Styles */
        * {
            box-sizing: border-box;
            margin: 0;
            padding: 0;
        }

        html {
            font-size: 16px;
            scroll-behavior: smooth;
        }

        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            line-height: 1.7;
            color: var(--text-color);
            background-color: var(--background-color);
            display: flex;
            flex-direction: column;
            min-height: 100vh;
        }

        a {
            color: var(--primary-color);
            text-decoration: none;
            transition: color var(--transition-speed) ease;
        }

        a:hover {
            color: #E55B5B;
            text-decoration: underline;
        }

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

        button, input, select, textarea {
            font-family: inherit;
            font-size: inherit;
            color: inherit;
        }

        h1, h2, h3, h4, h5, h6 {
            line-height: 1.3;
            margin-bottom: var(--spacing-unit);
            font-weight: 600;
        }

        h1 { font-size: 2.5rem; }
        h2 { font-size: 2rem; }
        h3 { font-size: 1.75rem; }
        h4 { font-size: 1.5rem; }
        h5 { font-size: 1.25rem; }
        h6 { font-size: 1rem; }

        .container {
            width: 90%;
            max-width: var(--container-max-width);
            margin: 0 auto;
            padding: 0 var(--spacing-unit);
        }

        /* Header & Navigation */
        header {
            background-color: var(--card-background);
            box-shadow: 0 2px 10px var(--hover-shadow);
            padding: var(--spacing-unit) 0;
            position: sticky;
            top: 0;
            z-index: 1000;
        }

        header nav {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: 1.8rem;
            font-weight: 700;
            color: var(--primary-color);
            text-decoration: none;
        }

        .nav-links ul {
            list-style: none;
            display: flex;
            gap: var(--spacing-unit) * 1.5;
        }

        .nav-links li a {
            color: var(--light-text-color);
            font-weight: 500;
            padding: 0.5rem 0.8rem;
            border-radius: var(--radius-small);
            transition: all var(--transition-speed) ease;
            position: relative;
        }

        .nav-links li a.active {
            color: var(--primary-color);
            font-weight: 700;
        }

        .nav-links li a:not(.active):hover {
            color: var(--primary-color);
            background-color: rgba(255, 107, 107, 0.1);
        }

        /* Hero Section */
        .hero {
            background-image: url('/assets/images/backpic/back-2.webp');
            background-size: cover;
            background-position: center;
            color: #FFFFFF;
            text-align: center;
            padding: var(--spacing-unit) * 5 0;
            position: relative;
            display: flex;
            align-items: center;
            justify-content: center;
            min-height: 50vh;
            overflow: hidden;
        }

        .hero::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: linear-gradient(rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.4));
            z-index: 1;
        }

        .hero-content {
            position: relative;
            z-index: 2;
            max-width: 800px;
        }

        .hero h1 {
            font-size: 3rem;
            margin-bottom: var(--spacing-unit) * 0.5;
            font-weight: 800;
            text-shadow: 2px 2px 8px rgba(0,0,0,0.5);
        }

        .hero p {
            font-size: 1.2rem;
            margin-bottom: var(--spacing-unit) * 2;
            opacity: 0.9;
            text-shadow: 1px 1px 5px rgba(0,0,0,0.4);
        }

        .btn {
            display: inline-block;
            background-color: var(--primary-color);
            color: #FFFFFF;
            padding: var(--spacing-unit) * 1.2 var(--spacing-unit) * 2.5;
            border-radius: var(--radius-large);
            font-weight: 700;
            font-size: 1.1rem;
            transition: background-color var(--transition-speed) ease, transform var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
            box-shadow: 0 4px 15px rgba(255, 107, 107, 0.4);
            margin-top: var(--spacing-unit);
        }

        .btn:hover {
            background-color: #E55B5B;
            transform: translateY(-3px);
            box-shadow: 0 6px 20px rgba(255, 107, 107, 0.5);
        }

        /* Main Content Section */
        main {
            flex-grow: 1;
            padding: var(--spacing-unit) * 4 0;
        }

        .section-title {
            text-align: center;
            margin-bottom: var(--spacing-unit) * 3;
            font-size: 2.2rem;
            font-weight: 700;
            color: var(--text-color);
        }

        .section-title span {
            color: var(--primary-color);
        }

        /* Category/Content Cards */
        .card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: var(--spacing-unit) * 2;
        }

        .card {
            background-color: var(--card-background);
            border-radius: var(--radius-large);
            box-shadow: var(--card-shadow);
            overflow: hidden;
            transition: transform var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
            display: flex;
            flex-direction: column;
        }

        .card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 25px rgba(0, 0, 0, 0.15);
        }

        .card-image {
            width: 100%;
            height: 200px; /* Fixed height for consistent look */
            object-fit: cover;
            border-bottom: 1px solid var(--border-color);
        }

        .card-content {
            padding: var(--spacing-unit) * 1.5;
            flex-grow: 1;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .card-title {
            font-size: 1.3rem;
            font-weight: 700;
            margin-bottom: var(--spacing-unit) * 0.5;
            color: var(--text-color);
            display: -webkit-box;
            -webkit-line-clamp: 2; /* Limit title to 2 lines */
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        .card-description {
            font-size: 0.95rem;
            color: var(--light-text-color);
            margin-bottom: var(--spacing-unit);
            display: -webkit-box;
            -webkit-line-clamp: 3; /* Limit description to 3 lines */
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        .card-link {
            color: var(--primary-color);
            font-weight: 600;
            display: inline-flex;
            align-items: center;
            gap: 0.5rem;
            margin-top: auto; /* Push to bottom */
        }

        .card-link:hover {
            text-decoration: none;
        }

        .card-link .icon {
            transition: transform var(--transition-speed) ease;
        }

        .card-link:hover .icon {
            transform: translateX(3px);
        }

        /* About Section */
        .about-section {
            padding: var(--spacing-unit) * 4 0;
            background-color: var(--card-background);
            border-top: 1px solid var(--border-color);
            border-bottom: 1px solid var(--border-color);
        }

        .about-content {
            display: flex;
            flex-wrap: wrap;
            gap: var(--spacing-unit) * 3;
            align-items: center;
            justify-content: center;
        }

        .about-text {
            flex: 1;
            min-width: 300px;
        }

        .about-text h2 {
            font-size: 2rem;
            margin-bottom: var(--spacing-unit) * 1.5;
        }

        .about-text p {
            margin-bottom: var(--spacing-unit);
        }

        .about-image {
            flex: 0 0 40%; /* Fixed width for image */
            min-width: 300px;
            border-radius: var(--radius-large);
            box-shadow: var(--card-shadow);
            overflow: hidden;
        }

        /* FAQ Section */
        .faq-section {
            padding: var(--spacing-unit) * 4 0;
        }

        .faq-item {
            margin-bottom: var(--spacing-unit);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-medium);
            background-color: var(--card-background);
            overflow: hidden;
        }

        .faq-question {
            padding: var(--spacing-unit) * 1.2 var(--spacing-unit) * 1.5;
            cursor: pointer;
            font-weight: 600;
            display: flex;
            justify-content: space-between;
            align-items: center;
            transition: background-color var(--transition-speed) ease;
        }

        .faq-question:hover {
            background-color: rgba(0,0,0,0.03);
        }

        .faq-question::after {
            content: '+';
            font-size: 1.5rem;
            transition: transform var(--transition-speed) ease;
        }

        .faq-item.open .faq-question::after {
            transform: rotate(45deg);
        }

        .faq-answer {
            padding: 0 var(--spacing-unit) * 1.5;
            max-height: 0;
            overflow: hidden;
            transition: max-height var(--transition-speed) ease-out, padding var(--transition-speed) ease-out;
            background-color: var(--background-color);
        }

        .faq-item.open .faq-answer {
            max-height: 200px; /* Adjust as needed */
            padding: var(--spacing-unit) * 1.2 var(--spacing-unit) * 1.5;
        }

        /* Call to Action (CTA) */
        .cta-section {
            background-color: var(--primary-color);
            color: #FFFFFF;
            padding: var(--spacing-unit) * 5 0;
            text-align: center;
            position: relative;
            overflow: hidden;
            display: flex;
            justify-content: center;
            align-items: center;
        }

        .cta-content {
            position: relative;
            z-index: 2;
            max-width: 800px;
        }

        .cta-section h2 {
            font-size: 2.5rem;
            font-weight: 800;
            margin-bottom: var(--spacing-unit);
        }

        .cta-section p {
            font-size: 1.1rem;
            margin-bottom: var(--spacing-unit) * 2;
            opacity: 0.9;
        }

        .cta-section .btn {
            background-color: #FFFFFF;
            color: var(--primary-color);
            box-shadow: 0 4px 15px rgba(255, 255, 255, 0.4);
        }

        .cta-section .btn:hover {
            background-color: #f0f0f0;
            box-shadow: 0 6px 20px rgba(255, 255, 255, 0.5);
        }

        /* Footer */
        footer {
            background-color: #333333;
            color: rgba(255, 255, 255, 0.7);
            padding: var(--spacing-unit) * 3 0;
            text-align: center;
            margin-top: auto; /* Pushes footer to bottom */
        }

        .footer-logo {
            font-size: 1.8rem;
            font-weight: 700;
            color: var(--primary-color);
            text-decoration: none;
            margin-bottom: var(--spacing-unit) * 1.5;
            display: block;
        }

        .footer-links {
            margin-bottom: var(--spacing-unit) * 1.5;
        }

        .footer-links a {
            color: rgba(255, 255, 255, 0.8);
            margin: 0 var(--spacing-unit);
            font-weight: 500;
            transition: color var(--transition-speed) ease;
        }

        .footer-links a:hover {
            color: #FFFFFF;
            text-decoration: underline;
        }

        .copyright {
            font-size: 0.9rem;
        }

        /* Responsive Design */
        @media (max-width: 1024px) {
            html { font-size: 15px; }
            .hero h1 { font-size: 2.5rem; }
            .hero p { font-size: 1.1rem; }
            .card-grid { grid-template-columns: repeat(2, 1fr); }
        }

        @media (max-width: 768px) {
            header nav {
                flex-direction: column;
                gap: var(--spacing-unit);
            }
            .nav-links ul {
                flex-direction: column;
                align-items: center;
                gap: var(--spacing-unit) * 0.5;
            }
            .nav-links li a { padding: 0.5rem 1rem; }

            .hero { padding: var(--spacing-unit) * 4 0; min-height: 40vh; }
            .hero h1 { font-size: 2.2rem; }
            .hero p { font-size: 1rem; }

            .section-title { font-size: 1.8rem; margin-bottom: var(--spacing-unit) * 2; }
            .card-grid { grid-template-columns: 1fr; }

            .about-content { flex-direction: column; }
            .about-image { width: 80%; margin: 0 auto; }

            .cta-section h2 { font-size: 2rem; }
            .cta-section p { font-size: 1rem; }
            .cta-section .btn { padding: var(--spacing-unit) * 1 var(--spacing-unit) * 2; font-size: 1rem; }

            .footer-links { display: flex; flex-direction: column; gap: var(--spacing-unit) * 0.5; }
            .footer-links a { margin: 0; }
        }

        @media (max-width: 520px) {
            .logo { font-size: 1.5rem; }
            .hero h1 { font-size: 1.8rem; }
            .hero p { font-size: 0.95rem; }
            .btn { padding: var(--spacing-unit) * 1 var(--spacing-unit) * 2; font-size: 1rem; }
            .about-image { width: 100%; }
        }

/* roulang page: category5 */
:root {
            --primary-color: #007bff;
            --secondary-color: #6c757d;
            --accent-color: #28a745;
            --background-color: #f8f9fa;
            --card-background: #ffffff;
            --text-color: #333;
            --light-text-color: #666;
            --border-color: #dee2e6;
            --border-radius: 8px;
            --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.05);
            --shadow-md: 0 4px 8px rgba(0, 0, 0, 0.1);
            --container-max-width: 1200px;
            --spacing-xs: 0.5rem;
            --spacing-sm: 1rem;
            --spacing-md: 1.5rem;
            --spacing-lg: 2rem;
            --spacing-xl: 3rem;
            --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            --line-height-base: 1.6;
        }

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

        body {
            font-family: var(--font-family);
            line-height: var(--line-height-base);
            color: var(--text-color);
            background-color: var(--background-color);
            scroll-behavior: smooth;
        }

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

        a {
            color: var(--primary-color);
            text-decoration: none;
            transition: color 0.3s ease;
        }

        a:hover {
            color: #0056b3;
        }

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

        h1, h2, h3, h4, h5, h6 {
            margin-bottom: var(--spacing-sm);
            line-height: 1.3;
            font-weight: 600;
        }

        h1 { font-size: 2.5rem; }
        h2 { font-size: 2rem; }
        h3 { font-size: 1.75rem; }
        h4 { font-size: 1.5rem; }

        .btn {
            display: inline-block;
            padding: var(--spacing-sm) var(--spacing-md);
            border-radius: var(--border-radius);
            border: none;
            cursor: pointer;
            font-weight: 500;
            transition: background-color 0.3s ease, color 0.3s ease, transform 0.2s ease, box-shadow 0.3s ease;
            text-align: center;
        }

        .btn-primary {
            background-color: var(--primary-color);
            color: #ffffff;
        }

        .btn-primary:hover {
            background-color: #0056b3;
            transform: translateY(-2px);
            box-shadow: var(--shadow-md);
        }

        .btn-accent {
            background-color: var(--accent-color);
            color: #ffffff;
        }

        .btn-accent:hover {
            background-color: #218838;
            transform: translateY(-2px);
            box-shadow: var(--shadow-md);
        }

        header {
            background-color: #ffffff;
            box-shadow: var(--shadow-sm);
            padding: var(--spacing-sm) 0;
            position: sticky;
            top: 0;
            z-index: 1000;
        }

        header .container {
            display: flex;
            justify-content: space-between;
            align-items: center;
        }

        .logo {
            font-size: 1.8rem;
            font-weight: bold;
            color: var(--primary-color);
        }

        nav ul {
            list-style: none;
            display: flex;
        }

        nav ul li {
            margin-left: var(--spacing-lg);
        }

        nav ul li a {
            color: var(--text-color);
            font-weight: 500;
            padding: var(--spacing-sm) 0;
            position: relative;
            transition: color 0.3s ease;
        }

        nav ul li a.active {
            color: var(--primary-color);
            font-weight: bold;
        }

        nav ul li a::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 0;
            height: 2px;
            background-color: var(--primary-color);
            transition: width 0.3s ease;
        }

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

        nav ul li a:hover::after,
        nav ul li a.active::after {
            width: 100%;
        }

        .hero {
            background-image: linear-gradient(rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)), url('/assets/images/backpic/back-3.webp');
            background-size: cover;
            background-position: center;
            color: #ffffff;
            text-align: center;
            padding: var(--spacing-xl) 0;
            position: relative;
        }

        .hero h1 {
            font-size: 3rem;
            margin-bottom: var(--spacing-sm);
        }

        .hero p {
            font-size: 1.2rem;
            margin-bottom: var(--spacing-lg);
        }

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

        .section-title {
            text-align: center;
            margin-bottom: var(--spacing-lg);
            font-size: 2.2rem;
            color: var(--primary-color);
        }

        .card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
            gap: var(--spacing-lg);
        }

        .card {
            background-color: var(--card-background);
            border-radius: var(--border-radius);
            box-shadow: var(--shadow-sm);
            overflow: hidden;
            transition: transform 0.3s ease, box-shadow 0.3s ease;
            display: flex;
            flex-direction: column;
        }

        .card:hover {
            transform: translateY(-5px);
            box-shadow: var(--shadow-md);
        }

        .card img {
            width: 100%;
            height: 200px; /* Fixed height for consistent card appearance */
            object-fit: cover;
        }

        .card-content {
            padding: var(--spacing-md);
            flex-grow: 1;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .card-title {
            font-size: 1.5rem;
            margin-bottom: var(--spacing-sm);
            color: var(--text-color);
        }

        .card-description {
            color: var(--light-text-color);
            margin-bottom: var(--spacing-md);
            flex-grow: 1;
        }

        .card-footer {
            margin-top: auto; /* Pushes to bottom */
        }

        .card-footer .btn {
            width: 100%;
        }

        .features-section .card-grid {
            grid-template-columns: repeat(3, 1fr);
        }

        .features-section .card {
            text-align: center;
            border: 1px solid var(--border-color);
        }

        .features-section .card img {
            height: auto; /* Allow image to be natural height within card */
            max-height: 150px;
            width: auto;
            margin: 0 auto var(--spacing-sm);
            object-fit: contain;
        }

        .features-section .card-title {
            font-size: 1.2rem;
        }

        .features-section .card-description {
            font-size: 0.95rem;
        }

        .cta-section {
            background-color: var(--primary-color);
            color: #ffffff;
            text-align: center;
            padding: var(--spacing-xl) 0;
        }

        .cta-section h2 {
            font-size: 2.5rem;
            margin-bottom: var(--spacing-sm);
        }

        .cta-section p {
            font-size: 1.2rem;
            margin-bottom: var(--spacing-lg);
        }

        .cta-section .btn-accent {
            background-color: var(--accent-color);
            color: #ffffff;
            padding: var(--spacing-sm) var(--spacing-xl);
            font-size: 1.1rem;
        }

        .cta-section .btn-accent:hover {
            background-color: #218838;
        }

        footer {
            background-color: var(--card-background);
            color: var(--light-text-color);
            padding: var(--spacing-lg) 0;
            text-align: center;
            border-top: 1px solid var(--border-color);
            margin-top: var(--spacing-xl);
        }

        footer .container {
            display: flex;
            flex-direction: column;
            align-items: center;
        }

        .footer-logo {
            font-size: 1.8rem;
            font-weight: bold;
            color: var(--primary-color);
            margin-bottom: var(--spacing-sm);
        }

        .footer-links {
            margin-bottom: var(--spacing-md);
        }

        .footer-links a {
            margin: 0 var(--spacing-sm);
            color: var(--light-text-color);
        }

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

        .copyright {
            font-size: 0.9rem;
        }

        /* Responsive Design */
        @media (max-width: 992px) {
            .features-section .card-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            nav ul {
                flex-direction: column;
                align-items: center;
                width: 100%;
                margin-top: var(--spacing-sm);
            }
            nav ul li {
                margin: var(--spacing-xs) 0;
            }
            header .container {
                flex-direction: column;
            }
            .logo {
                margin-bottom: var(--spacing-sm);
            }
            .hero h1 {
                font-size: 2.5rem;
            }
            .section-title {
                font-size: 1.8rem;
            }
        }

        @media (max-width: 768px) {
            h1 { font-size: 2rem; }
            h2 { font-size: 1.75rem; }
            .hero { padding: var(--spacing-lg) 0; }
            .hero h1 { font-size: 2.2rem; }
            .hero p { font-size: 1.1rem; }
            .section { padding: var(--spacing-lg) 0; }
            .card-grid {
                grid-template-columns: 1fr;
            }
            .features-section .card-grid {
                grid-template-columns: 1fr;
            }
            .cta-section h2 {
                font-size: 2rem;
            }
            .cta-section p {
                font-size: 1.1rem;
            }
        }

        @media (max-width: 520px) {
             .logo { font-size: 1.5rem; }
             .hero h1 { font-size: 1.8rem; }
             .hero p { font-size: 1rem; }
             .btn { padding: var(--spacing-xs) var(--spacing-md); }
             .footer-links a {
                display: block;
                margin: var(--spacing-xs) 0;
             }
        }