/* roulang page: index */
:root {
            --primary: #004D40;
            --accent: #FF6600;
            --text-dark: #333333;
            --text-light: #ffffff;
            --bg-gray: #f8f9fa;
            --border: #e0e0e0;
            --font-main: 'Helvetica Neue', Arial, sans-serif;
            --container-max: 1200px;
        }

        * { margin: 0; padding: 0; box-sizing: border-box; }
        body { font-family: var(--font-main); color: var(--text-dark); line-height: 1.7; background: #fff; }
        
        /* Layout */
        .container { max-width: var(--container-max); margin: 0 auto; padding: 0 20px; }
        section { padding: 80px 0; }
        
        /* Header */
        header { position: sticky; top: 0; z-index: 1000; background: rgba(255,255,255,0.95); backdrop-filter: blur(10px); border-bottom: 1px solid var(--border); }
        .top-bar { display: flex; justify-content: space-between; padding: 10px 0; font-size: 12px; border-bottom: 1px solid var(--bg-gray); }
        .nav-bar { display: flex; justify-content: space-between; align-items: center; padding: 20px 0; }
        .logo { font-size: 24px; font-weight: 700; color: var(--primary); text-decoration: none; }
        nav a { margin-left: 30px; text-decoration: none; color: var(--text-dark); font-weight: 500; transition: color 0.3s; }
        nav a:hover { color: var(--accent); }

        /* Hero */
        .hero { position: relative; padding: 120px 0; background: var(--primary); color: #fff; text-align: center; overflow: hidden; }
        .hero-bg { position: absolute; top: 0; left: 0; width: 100%; height: 100%; object-fit: cover; opacity: 0.2; }
        .hero-content { position: relative; z-index: 2; max-width: 800px; margin: 0 auto; }
        .hero h1 { font-size: 64px; margin-bottom: 20px; }
        .hero p { font-size: 20px; margin-bottom: 40px; opacity: 0.9; }
        .btn { display: inline-block; padding: 15px 35px; border-radius: 5px; text-decoration: none; font-weight: 600; cursor: pointer; transition: 0.3s; }
        .btn-accent { background: var(--accent); color: #fff; }
        .btn-white { background: transparent; border: 2px solid #fff; color: #fff; margin-left: 15px; }

        /* Sections */
        .section-title { text-align: center; margin-bottom: 60px; }
        .section-title h2 { font-size: 40px; color: var(--primary); }
        .grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
        .card { padding: 40px; border: 1px solid var(--border); border-radius: 10px; transition: transform 0.3s; background: #fff; }
        .card:hover { transform: translateY(-10px); box-shadow: 0 20px 40px rgba(0,0,0,0.1); }
        
        /* Stats Bar */
        .stats-bar { background: var(--primary); color: #fff; padding: 60px 0; }
        .stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); text-align: center; }
        .stat-item h3 { font-size: 48px; }

        /* Dark Section */
        .dark-section { background: #222; color: #fff; padding: 100px 0; }

        /* Footer */
        footer { background: var(--text-dark); color: #ccc; padding: 60px 0; font-size: 14px; }
        .footer-links { display: flex; justify-content: space-between; }

        @media (max-width: 768px) {
            .grid-3 { grid-template-columns: 1fr; }
            .stats-grid { grid-template-columns: 1fr 1fr; gap: 40px; }
            .hero h1 { font-size: 40px; }
            nav { display: none; }
        }