/* roulang page: index */
:root {
            --primary: #FF7F50;
            --secondary: #0984E3;
            --dark: #2D3436;
            --light: #F8F9FA;
            --text-main: #2D3436;
            --text-muted: #636E72;
            --bg-section: #FFFFFF;
            --bg-alt: #F1F4F8;
            --border-color: #DFE6E9;
            --radius: 12px;
            --shadow: 0 4px 12px rgba(0,0,0,0.05);
            --font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
        }

        * { box-sizing: border-box; margin: 0; padding: 0; }
        body { font-family: var(--font-family); color: var(--text-main); line-height: 1.7; background-color: #fff; }
        .container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
        
        /* Typography */
        h1, h2, h3 { color: var(--dark); font-weight: 700; line-height: 1.3; }
        h1 { font-size: 3rem; margin-bottom: 20px; }
        h2 { font-size: 2.2rem; margin-bottom: 40px; text-align: center; }
        p { color: var(--text-muted); margin-bottom: 15px; }

        /* Navigation */
        header { position: sticky; top: 0; background: rgba(255,255,255,0.95); z-index: 1000; border-bottom: 1px solid var(--border-color); padding: 15px 0; }
        nav { display: flex; justify-content: space-between; align-items: center; }
        .logo { font-size: 1.5rem; font-weight: 800; color: var(--primary); text-decoration: none; }
        .nav-links { display: flex; gap: 20px; }
        .nav-links a { text-decoration: none; color: var(--dark); font-weight: 500; padding: 5px 10px; transition: color 0.3s; }
        .nav-links a:hover { color: var(--primary); }
        .btn-cta { background: var(--primary); color: #fff; padding: 10px 20px; border-radius: 8px; text-decoration: none; font-weight: 600; }

        /* Hero */
        #hero { padding: 80px 0; background: linear-gradient(135deg, #f8f9fa 0%, #edf2f7 100%); display: flex; align-items: center; }
        .hero-content { flex: 1; padding-right: 40px; }
        .hero-image { flex: 1; border-radius: var(--radius); box-shadow: var(--shadow); overflow: hidden; }
        .hero-image img { width: 100%; height: auto; display: block; }

        /* Sections */
        section { padding: 80px 0; }
        .bg-alt-section { background-color: var(--bg-alt); }
        .grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
        .grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
        
        /* Components */
        .card { background: #fff; padding: 30px; border-radius: var(--radius); box-shadow: var(--shadow); transition: transform 0.3s; }
        .card:hover { transform: translateY(-5px); }
        .btn-primary { display: inline-block; background: var(--primary); color: #fff; padding: 12px 30px; border-radius: 8px; text-decoration: none; font-weight: 600; }

        /* Footer */
        footer { background: var(--dark); color: #fff; padding: 50px 0; text-align: center; }
        .footer-links { display: flex; justify-content: center; gap: 20px; margin-bottom: 20px; }
        .footer-links a { color: #ccc; text-decoration: none; }

        @media (max-width: 768px) {
            .grid-3, .grid-4 { grid-template-columns: 1fr; }
            .hero-content { padding-right: 0; margin-bottom: 40px; }
            #hero { flex-direction: column; text-align: center; }
            nav { flex-direction: column; gap: 15px; }
        }