/* roulang page: index */
:root {
            --primary: #00F2FF;
            --secondary: #1A1A1A;
            --accent: #FF6B35;
            --bg-body: #0A0A0A;
            --text-main: #ffffff;
            --text-muted: #a0a0a0;
            --card-bg: #1f1f1f;
            --radius: 12px;
            --shadow: 0 10px 30px rgba(0,0,0,0.3);
        }

        * { margin: 0; padding: 0; box-sizing: border-box; }
        body { font-family: 'Inter', -apple-system, sans-serif; background: var(--bg-body); color: var(--text-main); line-height: 1.6; }
        .container { max-width: 1200px; margin: 0 auto; padding: 0 20px; }
        a { text-decoration: none; color: inherit; transition: 0.3s; }
        ul { list-style: none; }
        button { cursor: pointer; border: none; outline: none; }

        /* Header */
        header { padding: 20px 0; background: rgba(26,26,26,0.95); position: sticky; top: 0; z-index: 1000; border-bottom: 1px solid #333; }
        nav { display: flex; justify-content: space-between; align-items: center; }
        .logo { font-size: 1.5rem; font-weight: 800; color: var(--primary); }
        .nav-links a { margin-left: 30px; font-weight: 500; font-size: 0.95rem; }
        .nav-links a:hover { color: var(--primary); }

        /* Sections */
        section { padding: 80px 0; }
        .section-title { font-size: 2.5rem; margin-bottom: 20px; text-align: center; }
        .section-desc { text-align: center; color: var(--text-muted); max-width: 700px; margin: 0 auto 50px; }

        /* Hero */
        .hero { min-height: 80vh; display: flex; align-items: center; background: linear-gradient(rgba(0,0,0,0.7), rgba(0,0,0,0.7)), url('/assets/images/What-is-Data-Analytics-in-Sports---Defined_-1.jpg') no-repeat center center/cover; }
        .hero-content { max-width: 800px; }
        .hero h1 { font-size: 4rem; margin-bottom: 20px; line-height: 1.1; }
        .hero p { font-size: 1.25rem; margin-bottom: 30px; color: #ddd; }
        .btn { padding: 15px 30px; background: linear-gradient(to right, var(--primary), #00aaff); color: #000; font-weight: 700; border-radius: var(--radius); display: inline-block; transition: 0.3s; }
        .btn:hover { transform: translateY(-3px); box-shadow: 0 5px 15px rgba(0,242,255,0.3); }

        /* Grid Cards */
        .grid-3 { display: grid; grid-template-columns: repeat(auto-fit, minmax(350px, 1fr)); gap: 30px; }
        .card { background: var(--card-bg); padding: 30px; border-radius: var(--radius); transition: 0.3s; border: 1px solid #333; }
        .card:hover { transform: translateY(-10px); border-color: var(--primary); }
        .card h3 { margin-bottom: 15px; color: var(--primary); }

        /* Data Strip */
        .data-strip { background: linear-gradient(90deg, #1A1A1A, #252525); padding: 40px 0; border-top: 1px solid #333; border-bottom: 1px solid #333; }
        .data-grid { display: flex; justify-content: space-around; text-align: center; }
        .data-item h4 { font-size: 2.5rem; color: var(--primary); }

        /* Dark Section */
        .bg-dark { background: #000; }

        /* Footer */
        footer { padding: 60px 0; background: #050505; color: var(--text-muted); font-size: 0.9rem; }
        .footer-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 40px; }

        @media (max-width: 768px) {
            .hero h1 { font-size: 2.5rem; }
            .grid-3 { grid-template-columns: 1fr; }
            .footer-grid { grid-template-columns: 1fr; }
        }