/* roulang page: index */
:root {
            --primary-color: #007bff;
            --secondary-color: #6c757d;
            --light-color: #f8f9fa;
            --dark-color: #343a40;
            --text-color: #212529;
            --muted-text-color: #6c757d;
            --border-color: #dee2e6;
            --border-radius: 0.25rem;
            --shadow: 0 0.125rem 0.25rem rgba(0, 0, 0, 0.075);
            --spacing-sm: 0.5rem;
            --spacing-md: 1rem;
            --spacing-lg: 1.5rem;
            --container-max-width: 1140px;
        }

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

        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(--light-color);
            display: flex;
            flex-direction: column;
            min-height: 100vh;
        }

        .container {
            width: 100%;
            max-width: var(--container-max-width);
            margin-left: auto;
            margin-right: auto;
            padding-left: var(--spacing-md);
            padding-right: var(--spacing-md);
        }

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

        a:hover {
            color: #0056b3;
            text-decoration: underline;
        }

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

        .btn {
            display: inline-block;
            font-weight: 400;
            text-align: center;
            vertical-align: middle;
            cursor: pointer;
            border: 1px solid transparent;
            padding: var(--spacing-sm) var(--spacing-md);
            font-size: 1rem;
            border-radius: var(--border-radius);
            transition: color 0.15s ease-in-out, background-color 0.15s ease-in-out, border-color 0.15s ease-in-out, box-shadow 0.15s ease-in-out;
        }

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

        .btn-primary:hover {
            color: #fff;
            background-color: #0056b3;
            border-color: #004085;
        }

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

        .btn-outline-primary:hover {
            color: #fff;
            background-color: var(--primary-color);
            border-color: var(--primary-color);
        }

        header {
            background-color: var(--dark-color);
            color: #fff;
            padding: var(--spacing-md) 0;
            box-shadow: var(--shadow);
        }

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

        .logo {
            font-size: 1.75rem;
            font-weight: bold;
            color: #fff;
            text-decoration: none;
        }
        .logo:hover {
            color: #fff;
            text-decoration: none;
        }

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

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

        nav ul li a {
            color: #fff;
            font-weight: 500;
            padding: var(--spacing-sm) 0;
            position: relative;
            text-decoration: none;
        }

        nav ul li a:hover,
        nav ul li a.active {
            color: var(--primary-color);
            text-decoration: none;
        }
        nav ul li a.active::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 0;
            width: 100%;
            height: 2px;
            background-color: var(--primary-color);
        }

        .hero {
            background-image: url('/assets/images/backpic/back-1.webp');
            background-size: cover;
            background-position: center;
            color: #fff;
            padding: var(--spacing-lg) 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);
        }
        .hero .container {
            position: relative;
            z-index: 1;
        }

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

        .hero p {
            font-size: 1.25rem;
            margin-bottom: var(--spacing-lg);
        }

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

        .section h2 {
            text-align: center;
            font-size: 2.25rem;
            margin-bottom: var(--spacing-lg);
            color: var(--dark-color);
        }

        .card {
            background-color: #fff;
            border: 1px solid var(--border-color);
            border-radius: var(--border-radius);
            box-shadow: var(--shadow);
            margin-bottom: var(--spacing-md);
            overflow: hidden;
            transition: transform 0.2s ease-in-out, box-shadow 0.2s ease-in-out;
        }

        .card:hover {
            transform: translateY(-5px);
            box-shadow: 0 0.5rem 1rem rgba(0, 0, 0, 0.15);
        }

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

        .card-body {
            padding: var(--spacing-md);
        }

        .card-title {
            font-size: 1.25rem;
            font-weight: 600;
            margin-bottom: var(--spacing-sm);
            color: var(--dark-color);
        }

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

        .card-footer {
            padding: var(--spacing-md);
            background-color: var(--light-color);
            border-top: 1px solid var(--border-color);
            font-size: 0.85rem;
            color: var(--muted-text-color);
        }

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

        .faq-section {
            background-color: #fff;
            padding: var(--spacing-lg) 0;
            border-top: 1px solid var(--border-color);
        }

        .faq-section h2 {
            margin-bottom: var(--spacing-lg);
        }

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

        .faq-question {
            font-weight: 600;
            cursor: pointer;
            position: relative;
            padding-left: var(--spacing-lg);
        }

        .faq-question::before {
            content: '+';
            position: absolute;
            left: 0;
            top: 0;
            font-size: 1.2rem;
            color: var(--primary-color);
            transition: transform 0.2s ease-in-out;
        }

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

        .faq-answer {
            margin-top: var(--spacing-sm);
            margin-left: var(--spacing-lg);
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s ease-out;
            color: var(--muted-text-color);
        }

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

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

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

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

        footer {
            background-color: var(--dark-color);
            color: #ccc;
            padding: var(--spacing-lg) 0;
            margin-top: auto; /* Pushes footer to the bottom */
        }

        footer .container {
            text-align: center;
        }

        .footer-nav ul {
            list-style: none;
            padding: 0;
            margin: 0 0 var(--spacing-md) 0;
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
        }

        .footer-nav ul li {
            margin: 0 var(--spacing-md);
        }

        .footer-nav ul li a {
            color: #ccc;
        }

        .footer-nav ul li a:hover {
            color: #fff;
        }

        .copyright {
            font-size: 0.9rem;
        }

        /* Responsive Design */
        @media (max-width: 992px) {
            .hero h1 {
                font-size: 2.5rem;
            }
        }

        @media (max-width: 768px) {
            header .container {
                flex-direction: column;
            }
            nav ul {
                margin-top: var(--spacing-md);
                flex-direction: column;
                align-items: center;
            }
            nav ul li {
                margin-left: 0;
                margin-bottom: var(--spacing-sm);
            }
            .hero h1 {
                font-size: 2rem;
            }
            .hero p {
                font-size: 1.1rem;
            }
            .section h2 {
                font-size: 2rem;
            }
            .cta-section h2 {
                font-size: 2rem;
            }
        }

        @media (max-width: 576px) {
            .container {
                padding-left: var(--spacing-sm);
                padding-right: var(--spacing-sm);
            }
            .hero h1 {
                font-size: 1.75rem;
            }
            .section h2,
            .cta-section h2 {
                font-size: 1.75rem;
            }
            .card-body, .card-footer {
                padding: var(--spacing-sm);
            }
            .footer-nav ul li {
                margin: 0 var(--spacing-sm);
            }
        }

/* roulang page: article */
:root {
            --primary-color: #007bff;
            --secondary-color: #6c757d;
            --light-color: #f8f9fa;
            --dark-color: #343a40;
            --accent-color: #ffc107;
            --background-color: #ffffff;
            --text-color: #212529;
            --weak-text-color: #6c757d;
            --border-color: #dee2e6;
            --card-background: #ffffff;
            --shadow-color: rgba(0, 0, 0, 0.1);
            --border-radius: 8px;
            --container-max-width: 1200px;
            --spacing-unit: 1rem;
            --section-padding: calc(var(--spacing-unit) * 3);
            --header-height: 70px;
            --footer-height: 100px;
        }

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

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

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            line-height: 1.7;
            color: var(--text-color);
            background-color: var(--background-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 0.3s ease;
        }

        a:hover, a:focus {
            color: var(--accent-color);
            text-decoration: underline;
        }

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

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

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

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

        ul {
            list-style: disc;
            margin-left: calc(var(--spacing-unit) * 1.5);
            margin-bottom: var(--spacing-unit);
        }

        ol {
            list-style: decimal;
            margin-left: calc(var(--spacing-unit) * 1.5);
            margin-bottom: var(--spacing-unit);
        }

        button, .btn {
            display: inline-block;
            padding: calc(var(--spacing-unit) * 0.75) calc(var(--spacing-unit) * 1.5);
            background-color: var(--primary-color);
            color: #fff;
            border: none;
            border-radius: var(--border-radius);
            cursor: pointer;
            font-size: 1rem;
            text-decoration: none;
            transition: background-color 0.3s ease, transform 0.2s ease, box-shadow 0.3s ease;
            border-bottom: 3px solid var(--primary-color);
        }

        button:hover, .btn:hover {
            background-color: var(--accent-color);
            border-bottom-color: var(--accent-color);
            color: #fff;
            text-decoration: none;
            transform: translateY(-2px);
            box-shadow: 0 4px 15px var(--shadow-color);
        }

        button:active, .btn:active {
            transform: translateY(0);
            box-shadow: none;
        }

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

        .btn-secondary:hover {
            background-color: var(--weak-text-color);
            border-bottom-color: var(--weak-text-color);
        }

        header {
            background-color: var(--card-background);
            box-shadow: 0 2px 5px var(--shadow-color);
            padding: calc(var(--spacing-unit) * 0.5) 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(--dark-color);
            transition: color 0.3s ease;
        }

        .logo:hover {
            color: var(--primary-color);
            text-decoration: none;
        }

        nav ul {
            list-style: none;
            margin: 0;
            display: flex;
        }

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

        nav ul li a {
            font-size: 1.1rem;
            font-weight: 500;
            color: var(--weak-text-color);
            padding: calc(var(--spacing-unit) * 0.5) 0;
            position: relative;
            transition: color 0.3s ease;
        }

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

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

        main {
            flex-grow: 1;
            padding-top: var(--section-padding);
            padding-bottom: var(--section-padding);
        }

        .article-content {
            background-color: var(--card-background);
            padding: calc(var(--spacing-unit) * 3);
            border-radius: var(--border-radius);
            box-shadow: 0 0 15px var(--shadow-color);
        }

        .article-content h1 {
            font-size: 2.5rem;
            margin-bottom: calc(var(--spacing-unit) * 1.5);
            color: var(--dark-color);
        }

        .article-meta {
            font-size: 0.9rem;
            color: var(--weak-text-color);
            margin-bottom: calc(var(--spacing-unit) * 2);
        }

        .article-meta span {
            margin-right: calc(var(--spacing-unit) * 2);
        }

        .article-body {
            font-size: 1.1rem;
            color: var(--text-color);
        }

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

        .article-body img {
            margin: var(--spacing-unit) auto;
            border-radius: var(--border-radius);
            box-shadow: 0 4px 10px var(--shadow-color);
        }

        .no-content {
            text-align: center;
            padding: var(--section-padding);
        }

        .no-content h2 {
            color: var(--secondary-color);
            margin-bottom: var(--spacing-unit);
        }

        .no-content p {
            font-size: 1.1rem;
            margin-bottom: var(--spacing-unit);
        }

        .no-content .btn {
            margin-top: var(--spacing-unit);
        }

        footer {
            background-color: var(--dark-color);
            color: #fff;
            padding: calc(var(--spacing-unit) * 2) 0;
            margin-top: auto;
        }

        footer .container {
            text-align: center;
        }

        .footer-nav ul {
            list-style: none;
            padding: 0;
            margin: 0 0 calc(var(--spacing-unit) * 1.5) 0;
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
        }

        .footer-nav ul li {
            margin: 0 var(--spacing-unit) calc(var(--spacing-unit) * 0.5) var(--spacing-unit);
        }

        .footer-nav ul li a {
            color: #ccc;
            font-weight: 500;
            transition: color 0.3s ease;
        }

        .footer-nav ul li a:hover {
            color: var(--accent-color);
            text-decoration: none;
        }

        .copyright {
            font-size: 0.9rem;
            color: #bbb;
            margin-top: var(--spacing-unit);
        }

        .copyright a {
            color: #ccc;
            text-decoration: underline;
        }

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

        /* Mobile Responsive */
        @media (max-width: 768px) {
            :root {
                --header-height: 60px;
                --section-padding: calc(var(--spacing-unit) * 2);
            }
            html {
                font-size: 15px;
            }
            h1 { font-size: 2rem; }
            h2 { font-size: 1.75rem; }
            h3 { font-size: 1.5rem; }

            .container {
                width: 95%;
            }

            header .container {
                flex-wrap: wrap;
                justify-content: center;
            }

            .logo {
                font-size: 1.5rem;
                margin-bottom: var(--spacing-unit);
            }

            nav ul {
                flex-direction: column;
                align-items: center;
            }

            nav ul li {
                margin: calc(var(--spacing-unit) * 0.5) 0;
            }

            .article-content {
                padding: calc(var(--spacing-unit) * 2);
            }

            .article-content h1 {
                font-size: 2rem;
            }

            .article-meta {
                font-size: 0.85rem;
                margin-bottom: calc(var(--spacing-unit) * 1.5);
            }

            .article-body {
                font-size: 1rem;
            }

            .footer-nav ul {
                flex-direction: column;
            }

            .footer-nav ul li {
                margin: 0 0 var(--spacing-unit) 0;
            }
        }

/* roulang page: category1 */
:root {
            --primary-color: #e53637;
            --secondary-color: #f5a623;
            --background-color: #f8f8f8;
            --text-color: #333;
            --text-muted: #777;
            --border-color: #ddd;
            --card-background: #fff;
            --container-width: 1200px;
            --spacing-unit: 16px;
            --border-radius: 8px;
            --box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
            --transition-speed: 0.3s;
        }

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

        body {
            font-family: 'Microsoft YaHei', 'PingFang SC', 'Hiragino Sans GB', sans-serif;
            line-height: 1.6;
            color: var(--text-color);
            background-color: var(--background-color);
            scroll-behavior: smooth;
        }

        .container {
            max-width: var(--container-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(--secondary-color);
        }

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

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

        header .container {
            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 {
            color: var(--secondary-color);
        }

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

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

        nav a {
            font-size: 1.1em;
            color: var(--text-color);
            font-weight: 500;
            padding: calc(var(--spacing-unit) / 2) 0;
            transition: color var(--transition-speed);
        }

        nav a.active,
        nav a:hover {
            color: var(--primary-color);
            border-bottom: 2px solid var(--primary-color);
        }

        .hero-section {
            background-image: url('/assets/images/backpic/back-1.webp');
            background-size: cover;
            background-position: center;
            color: #fff;
            text-align: center;
            padding: calc(var(--spacing-unit) * 6) var(--spacing-unit);
            position: relative;
            display: flex;
            align-items: center;
            justify-content: center;
            min-height: 60vh;
        }

        .hero-section::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(0, 0, 0, 0.5);
        }

        .hero-content {
            position: relative;
            z-index: 1;
        }

        .hero-content h1 {
            font-size: 3em;
            margin-bottom: var(--spacing-unit);
        }

        .hero-content p {
            font-size: 1.3em;
            margin-bottom: calc(var(--spacing-unit) * 3);
            max-width: 800px;
            margin-left: auto;
            margin-right: auto;
        }

        .cta-button {
            display: inline-block;
            background-color: var(--secondary-color);
            color: #fff;
            padding: calc(var(--spacing-unit) * 1.5) calc(var(--spacing-unit) * 3);
            font-size: 1.2em;
            border-radius: var(--border-radius);
            transition: background-color var(--transition-speed), transform var(--transition-speed);
            box-shadow: var(--box-shadow);
        }

        .cta-button:hover {
            background-color: var(--primary-color);
            transform: translateY(-3px);
        }

        .content-section {
            padding: calc(var(--spacing-unit) * 4) 0;
        }

        .content-section h2 {
            text-align: center;
            font-size: 2.5em;
            margin-bottom: calc(var(--spacing-unit) * 3);
            color: var(--text-color);
        }

        .card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
            gap: calc(var(--spacing-unit) * 2);
        }

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

        .video-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
        }

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

        .video-card-content {
            padding: calc(var(--spacing-unit) * 1.5);
            flex-grow: 1;
        }

        .video-card-content h3 {
            font-size: 1.4em;
            margin-bottom: var(--spacing-unit);
            color: var(--text-color);
            overflow: hidden;
            text-overflow: ellipsis;
            white-space: nowrap;
        }

        .video-card-content p {
            font-size: 0.95em;
            color: var(--text-muted);
            margin-bottom: var(--spacing-unit);
            display: -webkit-box;
            -webkit-line-clamp: 3;
            -webkit-box-orient: vertical;
            overflow: hidden;
        }

        .video-card-content .view-more {
            display: inline-block;
            margin-top: auto;
            font-weight: 500;
            color: var(--primary-color);
        }
        .video-card-content .view-more:hover {
            color: var(--secondary-color);
        }

        .features-section {
            background-color: #fff;
            padding: calc(var(--spacing-unit) * 4) 0;
        }

        .features-section .container {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: calc(var(--spacing-unit) * 3);
            text-align: center;
        }

        .feature-item {
            padding: var(--spacing-unit);
        }

        .feature-item i {
            font-size: 3em;
            color: var(--primary-color);
            margin-bottom: var(--spacing-unit);
        }

        .feature-item h3 {
            font-size: 1.5em;
            margin-bottom: var(--spacing-unit);
            color: var(--text-color);
        }

        .feature-item p {
            font-size: 1em;
            color: var(--text-muted);
        }

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

        .faq-section .container {
            max-width: 800px;
        }

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

        .faq-question {
            font-size: 1.2em;
            font-weight: 500;
            color: var(--text-color);
            padding: var(--spacing-unit) 0;
            cursor: pointer;
            position: relative;
        }
        .faq-question::after {
            content: '+';
            position: absolute;
            right: 0;
            font-size: 1.2em;
            color: var(--primary-color);
        }

        .faq-answer {
            font-size: 1em;
            color: var(--text-muted);
            padding-top: var(--spacing-unit);
            padding-bottom: var(--spacing-unit);
            max-height: 0;
            overflow: hidden;
            transition: max-height var(--transition-speed) ease-out;
            opacity: 0;
            transition: opacity var(--transition-speed) ease-out;
        }

        .faq-item.active .faq-question::after {
            content: '-';
        }

        .faq-item.active .faq-answer {
            max-height: 200px; /* Adjust as needed */
            opacity: 1;
        }

        .cta-section {
            background-color: var(--primary-color);
            color: #fff;
            text-align: center;
            padding: calc(var(--spacing-unit) * 4) var(--spacing-unit);
        }

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

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

        footer {
            background-color: #222;
            color: #ccc;
            padding: calc(var(--spacing-unit) * 3) 0;
            text-align: center;
            font-size: 0.9em;
        }

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

        .footer-nav ul {
            list-style: none;
            margin-bottom: var(--spacing-unit);
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
        }

        .footer-nav li {
            margin: 0 calc(var(--spacing-unit) * 1.5);
        }

        .footer-nav a {
            color: #ccc;
            transition: color var(--transition-speed);
        }

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

        .copyright {
            margin-top: var(--spacing-unit);
        }

        .copyright a {
            color: #ccc;
        }
        .copyright a:hover {
            color: var(--secondary-color);
        }

        /* Responsive Design */
        @media (max-width: 992px) {
            .container {
                padding: 0 calc(var(--spacing-unit) / 2);
            }
            .hero-content h1 {
                font-size: 2.5em;
            }
            .hero-content p {
                font-size: 1.1em;
            }
            .features-section .container {
                grid-template-columns: repeat(2, 1fr);
            }
        }

        @media (max-width: 768px) {
            header .container {
                flex-direction: column;
            }
            nav ul {
                margin-top: var(--spacing-unit);
                flex-direction: column;
                align-items: center;
            }
            nav li {
                margin: calc(var(--spacing-unit) / 2) 0;
            }
            .hero-section {
                padding: calc(var(--spacing-unit) * 4) var(--spacing-unit);
                min-height: 40vh;
            }
            .hero-content h1 {
                font-size: 2em;
            }
            .hero-content p {
                font-size: 1em;
            }
            .content-section h2 {
                font-size: 2em;
            }
            .card-grid {
                grid-template-columns: 1fr;
            }
            .features-section .container {
                grid-template-columns: 1fr;
            }
            .cta-section h2 {
                font-size: 2em;
            }
            .footer-nav ul {
                flex-direction: column;
            }
            .footer-nav li {
                margin: calc(var(--spacing-unit) / 2) 0;
            }
        }

        @media (max-width: 520px) {
            .logo {
                font-size: 1.5em;
            }
            .cta-button {
                padding: var(--spacing-unit) calc(var(--spacing-unit) * 2);
                font-size: 1em;
            }
        }

/* roulang page: category2 */
:root {
            --primary-color: #e91e63; /* Pink dominant */
            --secondary-color: #ffc107; /* Amber accent */
            --background-color: #f8f9fa;
            --text-color: #333;
            --muted-text-color: #6c757d;
            --border-color: #dee2e6;
            --card-background: #ffffff;
            --shadow-color: rgba(0, 0, 0, 0.1);
            --container-max-width: 1200px;
            --spacing-unit: 1rem;
            --border-radius: 0.5rem;
            --transition-speed: 0.3s;
        }

        body {
            font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
            margin: 0;
            padding: 0;
            color: var(--text-color);
            background-color: var(--background-color);
            line-height: 1.7;
            box-sizing: border-box;
        }

        *, *::before, *::after {
            box-sizing: inherit;
        }

        .container {
            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) ease;
        }

        a:hover, a:focus {
            color: #c2185b;
            text-decoration: underline;
        }

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

        h1, h2, h3, h4, h5, h6 {
            margin-top: 0;
            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; }

        /* Header & Navigation */
        header {
            background-color: var(--card-background);
            padding: var(--spacing-unit) 0;
            box-shadow: 0 2px 4px rgba(0,0,0,0.05);
            border-bottom: 1px solid var(--border-color);
        }

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

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

        nav ul {
            list-style: none;
            padding: 0;
            margin: 0;
            display: flex;
        }

        nav ul li {
            margin-left: calc(var(--spacing-unit) * 1.5);
        }

        nav ul li a {
            color: var(--text-color);
            font-weight: 500;
            padding: 0.5rem 0;
            position: relative;
            text-decoration: none;
            transition: color var(--transition-speed) ease;
        }

        nav ul li a:hover,
        nav ul li a.active {
            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-1.webp');
            background-size: cover;
            background-position: center;
            color: #fff;
            text-align: center;
            padding: calc(var(--spacing-unit) * 6) calc(var(--spacing-unit) * 2);
            position: relative;
            display: flex;
            flex-direction: column;
            justify-content: center;
            align-items: center;
            min-height: 500px; /* Adjust as needed */
        }

        .hero::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            right: 0;
            bottom: 0;
            background: rgba(0, 0, 0, 0.5); /* Overlay for text readability */
        }

        .hero .hero-content {
            position: relative;
            z-index: 1;
            max-width: 800px;
        }

        .hero h1 {
            font-size: 3.5rem;
            margin-bottom: var(--spacing-unit);
            color: #fff;
        }

        .hero p {
            font-size: 1.3rem;
            color: #e0e0e0;
            margin-bottom: calc(var(--spacing-unit) * 2);
        }

        .cta-button {
            display: inline-block;
            background-color: var(--secondary-color);
            color: var(--text-color);
            padding: calc(var(--spacing-unit) * 1.2) calc(var(--spacing-unit) * 2.5);
            border-radius: var(--border-radius);
            font-size: 1.1rem;
            font-weight: bold;
            transition: background-color var(--transition-speed) ease, transform var(--transition-speed) ease;
            box-shadow: 0 4px 8px rgba(0,0,0,0.2);
            border: none;
            cursor: pointer;
        }

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

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

        .section h2 {
            text-align: center;
            font-size: 2.2rem;
            margin-bottom: calc(var(--spacing-unit) * 2.5);
            position: relative;
            padding-bottom: var(--spacing-unit);
        }

        .section h2::after {
            content: '';
            position: absolute;
            bottom: 0;
            left: 50%;
            transform: translateX(-50%);
            width: 60px;
            height: 4px;
            background-color: var(--primary-color);
            border-radius: 2px;
        }

        /* Card Styling */
        .card {
            background-color: var(--card-background);
            border-radius: var(--border-radius);
            box-shadow: 0 4px 12px var(--shadow-color);
            overflow: hidden;
            transition: transform var(--transition-speed) ease, box-shadow var(--transition-speed) ease;
            margin-bottom: calc(var(--spacing-unit) * 2);
            display: flex;
            flex-direction: column;
        }

        .card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 20px var(--shadow-color);
        }

        .card img {
            width: 100%;
            height: 220px; /* Fixed height for consistency */
            object-fit: cover;
        }

        .card-content {
            padding: var(--spacing-unit) calc(var(--spacing-unit) * 1.2);
            flex-grow: 1;
            display: flex;
            flex-direction: column;
        }

        .card-content h3 {
            font-size: 1.3rem;
            margin-bottom: calc(var(--spacing-unit) * 0.5);
            color: var(--primary-color);
        }

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

        .card-footer {
            padding: var(--spacing-unit) calc(var(--spacing-unit) * 1.2);
            background-color: var(--background-color);
            border-top: 1px solid var(--border-color);
            text-align: right;
        }

        .card-footer a {
            font-weight: 500;
        }

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

        /* FAQ Section */
        .faq-section {
            background-color: var(--card-background);
            border-radius: var(--border-radius);
            padding: calc(var(--spacing-unit) * 3) 0;
            margin-top: calc(var(--spacing-unit) * 4);
        }

        .faq-section h2 {
            margin-bottom: calc(var(--spacing-unit) * 2);
        }

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

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

        .faq-question {
            cursor: pointer;
            font-weight: 500;
            font-size: 1.1rem;
            display: flex;
            justify-content: space-between;
            align-items: center;
            padding: var(--spacing-unit) 0;
        }

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

        .faq-item.open .faq-question::after {
            content: '-';
            transform: rotate(180deg);
        }

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

        .faq-item.open .faq-answer {
            max-height: 150px; /* Adjust based on content */
            padding-top: var(--spacing-unit);
        }

        /* Footer */
        footer {
            background-color: #343a40;
            color: #ccc;
            padding: calc(var(--spacing-unit) * 3) 0;
            text-align: center;
            margin-top: calc(var(--spacing-unit) * 4);
        }

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

        .footer-nav ul {
            list-style: none;
            padding: 0;
            margin: 0 0 var(--spacing-unit) 0;
            display: flex;
            flex-wrap: wrap;
            justify-content: center;
        }

        .footer-nav ul li {
            margin: 0 calc(var(--spacing-unit) * 1.2);
        }

        .footer-nav ul li a {
            color: #ccc;
            transition: color var(--transition-speed) ease;
        }

        .footer-nav ul li a:hover {
            color: #fff;
        }

        .copyright {
            font-size: 0.9rem;
            margin: 0;
        }

        .copyright a {
            color: #ccc;
            margin: 0 0.5rem;
        }

        .copyright a:hover {
            color: #fff;
        }

        /* Responsive Adjustments */
        @media (max-width: 992px) {
            .hero h1 { font-size: 3rem; }
            .hero p { font-size: 1.1rem; }
            .section h2 { font-size: 2rem; }
        }

        @media (max-width: 768px) {
            header .container {
                flex-direction: column;
            }
            nav ul {
                margin-top: var(--spacing-unit);
                flex-wrap: wrap;
                justify-content: center;
            }
            nav ul li {
                margin: 0.5rem calc(var(--spacing-unit) * 1.2);
            }
            .hero {
                min-height: 400px;
                padding: calc(var(--spacing-unit) * 4) var(--spacing-unit);
            }
            .hero h1 { font-size: 2.5rem; }
            .hero p { font-size: 1rem; }
            .card-grid {
                grid-template-columns: 1fr;
            }
            .footer-nav ul {
                flex-direction: column;
            }
            .footer-nav ul li {
                margin: 0.5rem 0;
            }
        }

        @media (max-width: 576px) {
            .logo { font-size: 1.5rem; }
            .hero h1 { font-size: 2rem; }
            .cta-button {
                padding: 0.8rem 1.8rem;
                font-size: 1rem;
            }
            .section {
                padding: calc(var(--spacing-unit) * 3) 0;
            }
            .section h2 {
                font-size: 1.75rem;
                margin-bottom: var(--spacing-unit) * 2;
            }
            .card-content {
                padding: var(--spacing-unit);
            }
            .card-content h3 {
                font-size: 1.15rem;
            }
        }

/* roulang page: category3 */
:root {
            --primary-color: #ff6f61;
            --secondary-color: #f7d08a;
            --background-color: #f4f4f4;
            --text-color: #333;
            --weak-text-color: #777;
            --border-color: #ddd;
            --border-radius: 8px;
            --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
            --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
            --spacing-xs: 8px;
            --spacing-sm: 16px;
            --spacing-md: 24px;
            --spacing-lg: 32px;
        }

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

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

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

        header {
            background-color: #fff;
            box-shadow: var(--shadow-sm);
            padding: var(--spacing-sm) 0;
            border-bottom: 1px solid var(--border-color);
        }

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

        .logo {
            font-size: 24px;
            font-weight: bold;
            color: var(--primary-color);
            text-decoration: none;
        }

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

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

        nav ul li a {
            text-decoration: none;
            color: var(--text-color);
            font-weight: 500;
            transition: color 0.3s ease;
        }

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

        .hero {
            background-image: url('/assets/images/backpic/back-3.webp');
            background-size: cover;
            background-position: center;
            color: #fff;
            text-align: center;
            padding: var(--spacing-lg) 0;
            position: relative;
        }

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

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

        .hero h1 {
            font-size: 40px;
            margin-bottom: var(--spacing-sm);
        }

        .hero p {
            font-size: 18px;
            margin-bottom: var(--spacing-md);
        }

        .btn {
            display: inline-block;
            background-color: var(--primary-color);
            color: #fff;
            padding: var(--spacing-sm) var(--spacing-lg);
            text-decoration: none;
            border-radius: var(--border-radius);
            transition: background-color 0.3s ease, transform 0.2s ease;
            border: none;
            cursor: pointer;
            font-size: 16px;
        }

        .btn:hover {
            background-color: #e65c50;
            transform: translateY(-2px);
        }

        main .container {
            padding: var(--spacing-lg) 0;
        }

        .section-title {
            text-align: center;
            font-size: 32px;
            margin-bottom: var(--spacing-md);
            color: var(--text-color);
        }

        .video-grid {
            display: grid;
            grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
            gap: var(--spacing-md);
        }

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

        .video-card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 12px rgba(0, 0, 0, 0.15);
        }

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

        .video-card-content {
            padding: var(--spacing-sm);
            flex-grow: 1;
        }

        .video-card-title {
            font-size: 18px;
            margin-bottom: var(--spacing-xs);
            color: var(--text-color);
            text-decoration: none;
        }

        .video-card-description {
            font-size: 14px;
            color: var(--weak-text-color);
            margin-bottom: var(--spacing-sm);
        }

        .video-card-meta {
            font-size: 12px;
            color: var(--weak-text-color);
            display: flex;
            justify-content: space-between;
        }

        .features-section {
            background-color: #fff;
            padding: var(--spacing-lg) 0;
        }

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

        .feature-item {
            text-align: center;
        }

        .feature-item i {
            font-size: 36px;
            color: var(--primary-color);
            margin-bottom: var(--spacing-sm);
        }

        .feature-item h3 {
            font-size: 20px;
            margin-bottom: var(--spacing-xs);
        }

        .feature-item p {
            font-size: 14px;
            color: var(--weak-text-color);
        }

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

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

        .faq-question {
            font-size: 18px;
            font-weight: bold;
            cursor: pointer;
            position: relative;
            padding-left: 25px;
        }

        .faq-question::before {
            content: '+';
            position: absolute;
            left: 0;
            font-weight: bold;
            color: var(--primary-color);
        }

        .faq-question.active::before {
            content: '-';
        }

        .faq-answer {
            font-size: 14px;
            color: var(--weak-text-color);
            padding-left: 25px;
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s ease-out;
        }

        .faq-answer p {
            margin-top: var(--spacing-xs);
        }

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

        .cta-section h2 {
            font-size: 36px;
            margin-bottom: var(--spacing-sm);
        }

        .cta-section p {
            font-size: 18px;
            margin-bottom: var(--spacing-md);
        }

        footer {
            background-color: #333;
            color: #ccc;
            padding: var(--spacing-lg) 0;
            text-align: center;
            font-size: 14px;
        }

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

        .footer-nav ul {
            list-style: none;
            display: flex;
            margin-bottom: var(--spacing-sm);
        }

        .footer-nav ul li {
            margin: 0 var(--spacing-md);
        }

        .footer-nav ul li a {
            color: #ccc;
            text-decoration: none;
            transition: color 0.3s ease;
        }

        .footer-nav ul li a:hover {
            color: #fff;
        }

        .copyright {
            margin-top: var(--spacing-sm);
        }

        .copyright a {
            color: #ccc;
            text-decoration: none;
            transition: color 0.3s ease;
        }

        .copyright a:hover {
            color: #fff;
        }

        /* Responsive Styles */
        @media (max-width: 768px) {
            nav ul {
                flex-direction: column;
                align-items: center;
            }
            nav ul li {
                margin: var(--spacing-xs) 0;
            }
            .hero h1 {
                font-size: 32px;
            }
            .hero p {
                font-size: 16px;
            }
            .features-grid {
                grid-template-columns: 1fr;
            }
            .video-grid {
                grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
            }
        }

        @media (max-width: 520px) {
            .logo {
                font-size: 20px;
            }
            .hero h1 {
                font-size: 28px;
            }
            .hero p {
                font-size: 14px;
            }
            .footer-nav ul {
                flex-direction: column;
            }
            .footer-nav ul li {
                margin: var(--spacing-xs) 0;
            }
        }

/* roulang page: category4 */
:root {
            --primary-color: #e91e63;
            --secondary-color: #f50057;
            --background-color: #121212;
            --text-color: #ffffff;
            --subtle-text-color: #bbbbbb;
            --border-color: #333333;
            --card-background: #1e1e1e;
            --button-hover-bg: #d81b60;
            --footer-bg: #1a1a1a;
            --container-max-width: 1200px;
            --spacing-unit: 16px;
            --card-radius: 8px;
            --shadow-card: 0 4px 12px rgba(0, 0, 0, 0.5);
            --transition-base: all 0.3s ease;
        }

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

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

        body {
            font-family: 'Segoe UI', 'Microsoft YaHei', sans-serif;
            background-color: var(--background-color);
            color: var(--text-color);
            margin: 0;
            padding: 0;
            overflow-x: hidden;
        }

        .container {
            max-width: var(--container-max-width);
            margin: 0 auto;
            padding: 0 calc(var(--spacing-unit) * 1.5);
        }

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

        a:hover {
            color: var(--secondary-color);
            text-decoration: underline;
        }

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

        h1, h2, h3, h4, h5, h6 {
            margin-bottom: var(--spacing-unit);
            line-height: 1.3;
            font-weight: 700;
        }

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

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

        .btn {
            display: inline-block;
            padding: calc(var(--spacing-unit) * 0.8) calc(var(--spacing-unit) * 1.6);
            background-color: var(--primary-color);
            color: var(--text-color);
            border: none;
            border-radius: var(--card-radius);
            cursor: pointer;
            font-size: 1rem;
            font-weight: 600;
            text-decoration: none;
            transition: var(--transition-base);
            box-shadow: 0 2px 5px rgba(0,0,0,0.3);
        }

        .btn:hover, .btn:focus {
            background-color: var(--button-hover-bg);
            color: var(--text-color);
            text-decoration: none;
            box-shadow: 0 4px 12px rgba(0,0,0,0.4);
            transform: translateY(-2px);
        }

        .btn.btn-secondary {
            background-color: var(--secondary-color);
        }
        .btn.btn-secondary:hover, .btn.btn-secondary:focus {
            background-color: #d81b60; /* Darker shade for hover */
        }

        /* Header */
        header {
            background-color: var(--card-background);
            padding: var(--spacing-unit) 0;
            border-bottom: 1px solid var(--border-color);
            position: sticky;
            top: 0;
            z-index: 1000;
        }

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

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

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

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

        header nav ul li a {
            color: var(--subtle-text-color);
            font-weight: 500;
            padding: 0.5rem 0;
            position: relative;
            transition: var(--transition-base);
        }

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

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

        /* Hero Section */
        .hero {
            background-image: linear-gradient(rgba(18, 18, 18, 0.8), rgba(18, 18, 18, 0.8)), url('/assets/images/backpic/back-3.webp');
            background-size: cover;
            background-position: center;
            color: var(--text-color);
            padding: calc(var(--spacing-unit) * 8) 0;
            text-align: center;
            position: relative;
            overflow: hidden;
        }

        .hero::before {
            content: '';
            position: absolute;
            top: 0;
            left: 0;
            width: 100%;
            height: 100%;
            background-image: linear-gradient(to top, rgba(18, 18, 18, 0.8), rgba(18, 18, 18, 0.2));
            z-index: 1;
        }

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

        .hero h1 {
            font-size: 3rem;
            margin-bottom: calc(var(--spacing-unit) * 2);
            color: var(--primary-color);
        }

        .hero p {
            font-size: 1.2rem;
            max-width: 700px;
            margin: 0 auto var(--spacing-unit);
            color: var(--subtle-text-color);
        }

        /* Section */
        section {
            padding: calc(var(--spacing-unit) * 6) 0;
        }

        section h2 {
            text-align: center;
            margin-bottom: calc(var(--spacing-unit) * 4);
            font-size: 2.5rem;
        }

        .card-grid {
            display: grid;
            grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
            gap: calc(var(--spacing-unit) * 3);
        }

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

        .card:hover {
            transform: translateY(-5px);
            box-shadow: 0 8px 20px rgba(0, 0, 0, 0.6);
        }

        .card img {
            width: 100%;
            height: 220px;
            object-fit: cover;
            border-bottom: 1px solid var(--border-color);
        }

        .card-content {
            padding: calc(var(--spacing-unit) * 2);
            flex-grow: 1;
            display: flex;
            flex-direction: column;
        }

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

        .card-content p {
            font-size: 0.95rem;
            color: var(--subtle-text-color);
            margin-bottom: calc(var(--spacing-unit) * 1.5);
            flex-grow: 1;
        }

        .card-content .btn {
            margin-top: auto; /* Pushes button to the bottom */
            display: block;
            width: 100%;
            text-align: center;
        }

        /* Category Specific Section */
        .category-description {
            text-align: center;
            margin-bottom: calc(var(--spacing-unit) * 5);
            color: var(--subtle-text-color);
            font-size: 1.1rem;
        }

        .category-features {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: calc(var(--spacing-unit) * 2);
            margin-bottom: calc(var(--spacing-unit) * 6);
        }

        .feature-item {
            text-align: center;
            padding: var(--spacing-unit);
        }

        .feature-item i { /* Assuming Font Awesome or similar for icons, placeholder */
            font-size: 2.5rem;
            color: var(--primary-color);
            margin-bottom: var(--spacing-unit);
        }

        .feature-item h4 {
            font-size: 1.2rem;
            margin-bottom: calc(var(--spacing-unit) / 2);
        }

        .feature-item p {
            font-size: 0.9rem;
            color: var(--subtle-text-color);
        }

        /* FAQ Section */
        .faq-section {
            background-color: var(--card-background);
            padding: calc(var(--spacing-unit) * 6) 0;
        }

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

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

        .faq-question {
            display: flex;
            justify-content: space-between;
            align-items: center;
            cursor: pointer;
            font-size: 1.15rem;
            font-weight: 500;
            padding: var(--spacing-unit) 0;
            color: var(--primary-color);
        }

        .faq-question::after {
            content: '+';
            font-size: 1.5rem;
            color: var(--subtle-text-color);
            transition: transform 0.3s ease;
        }

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

        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.3s ease-out;
            font-size: 0.95rem;
            color: var(--subtle-text-color);
            padding-top: 0;
        }

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

        /* CTA Section */
        .cta-section {
            background-image: linear-gradient(rgba(30, 30, 30, 0.9), rgba(30, 30, 30, 0.9)), url('/assets/images/backpic/back-1.webp');
            background-size: cover;
            background-position: center;
            text-align: center;
            padding: calc(var(--spacing-unit) * 7) 0;
            color: var(--text-color);
            position: relative;
        }

        .cta-section h2 {
            font-size: 2.8rem;
            margin-bottom: calc(var(--spacing-unit) * 2);
        }

        .cta-section p {
            font-size: 1.15rem;
            max-width: 700px;
            margin: 0 auto var(--spacing-unit);
            color: var(--subtle-text-color);
        }

        /* Footer */
        footer {
            background-color: var(--footer-bg);
            padding: calc(var(--spacing-unit) * 4) 0;
            color: var(--subtle-text-color);
            font-size: 0.9rem;
        }

        footer .container {
            text-align: center;
        }

        .footer-nav ul {
            list-style: none;
            display: flex;
            justify-content: center;
            flex-wrap: wrap;
            margin-bottom: calc(var(--spacing-unit) * 2);
        }

        .footer-nav ul li {
            margin: 0 calc(var(--spacing-unit) * 1.5);
        }

        .footer-nav ul li a {
            color: var(--subtle-text-color);
            transition: var(--transition-base);
        }

        .footer-nav ul li a:hover {
            color: var(--text-color);
        }

        .copyright {
            margin-top: var(--spacing-unit);
        }

        .copyright a {
            color: var(--subtle-text-color);
        }
        .copyright a:hover {
            color: var(--text-color);
        }

        /* Responsive Design */
        @media (max-width: 992px) {
            h1 { font-size: 2.2rem; }
            h2 { font-size: 1.8rem; }
            .hero h1 { font-size: 2.5rem; }
            .hero p { font-size: 1.1rem; }
            .card-grid { grid-template-columns: repeat(2, 1fr); }
            .category-features { grid-template-columns: repeat(2, 1fr); }
            header .logo { font-size: 1.5rem; }
            header nav ul { display: none; } /* Hamburger menu needed */
        }

        @media (max-width: 768px) {
            .card-grid { grid-template-columns: 1fr; }
            .category-features { grid-template-columns: 1fr; }
            .hero { padding: calc(var(--spacing-unit) * 5) 0; }
            .hero h1 { font-size: 2.2rem; }
            .cta-section { padding: calc(var(--spacing-unit) * 5) 0; }
            .cta-section h2 { font-size: 2.2rem; }
            .footer-nav ul li { margin: 0 var(--spacing-unit); }
        }

        @media (max-width: 576px) {
            html { font-size: 15px; }
            .hero h1 { font-size: 2rem; }
            .hero p { font-size: 1rem; }
            section { padding: calc(var(--spacing-unit) * 4) 0; }
            .card-content { padding: var(--spacing-unit); }
            .card-content h3 { font-size: 1.2rem; }
            .card-content p { margin-bottom: var(--spacing-unit); }
            .btn { padding: 0.7rem 1.3rem; }
        }