/* roulang page: index */
:root {
            --primary-color: #0052CC;
            --text-color: #2D3436;
            --light-bg: #F4F7FB;
            --border-color: #E1E8ED;
            --white: #FFFFFF;
            --transition: all 0.3s ease;
            --container-width: 1200px;
        }

        * { box-sizing: border-box; margin: 0; padding: 0; }
        body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif; line-height: 1.6; color: var(--text-color); background-color: #fff; scroll-behavior: smooth; }
        .container { max-width: var(--container-width); margin: 0 auto; padding: 0 20px; }
        
        /* Header */
        header { position: sticky; top: 0; background: rgba(255,255,255,0.95); backdrop-filter: blur(10px); border-bottom: 1px solid var(--border-color); z-index: 1000; padding: 15px 0; }
        nav { display: flex; justify-content: space-between; align-items: center; }
        .logo { font-size: 20px; font-weight: bold; color: var(--primary-color); text-decoration: none; }
        .nav-links a { margin-left: 25px; text-decoration: none; color: var(--text-color); font-weight: 500; }
        .nav-links a:hover { color: var(--primary-color); }
        .cta-header { background: var(--primary-color); color: #fff; padding: 8px 20px; border-radius: 6px; }

        /* Hero */
        .hero { padding: 120px 0; background-image: linear-gradient(rgba(0,0,0,0.6), rgba(0,0,0,0.6)), url('/assets/images/791ef76310186ca2.png'); background-size: cover; background-position: center; color: #fff; text-align: center; }
        .hero h1 { font-size: 48px; margin-bottom: 20px; }
        .hero p { font-size: 20px; margin-bottom: 40px; max-width: 700px; margin-left: auto; margin-right: auto; }
        .btn-main { display: inline-block; padding: 16px 40px; background: var(--primary-color); color: #fff; text-decoration: none; border-radius: 8px; font-weight: bold; }

        /* Sections */
        section { padding: 80px 0; }
        .section-title { text-align: center; font-size: 36px; margin-bottom: 50px; }
        .bg-light { background-color: var(--light-bg); }

        /* Components */
        .grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; }
        .grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 30px; }
        .card { background: #fff; padding: 30px; border-radius: 12px; box-shadow: 0 4px 12px rgba(0,0,0,0.05); transition: var(--transition); }
        .card:hover { transform: translateY(-5px); }
        .card h3 { margin-bottom: 15px; }
        
        /* Specific Components */
        .stat-card { text-align: center; }
        .stat-num { font-size: 40px; font-weight: bold; color: var(--primary-color); display: block; }

        /* FAQ */
        .faq-item { border-bottom: 1px solid var(--border-color); padding: 20px 0; }
        .faq-item summary { cursor: pointer; font-weight: 600; list-style: none; }

        /* Footer */
        footer { background: #1B1E21; color: #ccc; padding: 60px 0; text-align: center; }

        @media (max-width: 768px) {
            .grid-4, .grid-3 { grid-template-columns: 1fr; }
            .hero { padding: 60px 20px; }
            .hero h1 { font-size: 32px; }
        }