:root {
            --primary: #162d3d;
            --accent: #1dcaff;
            --text: #333;
            --white: #ffffff;
            --bg: #f9f9f9;
        }

        * { box-sizing: border-box; }
        body { font-family: 'Helvetica Neue', Helvetica, Arial, sans-serif; margin: 0; color: var(--text); line-height: 1.6; }
        
        header { background: var(--white); padding: 1rem; border-bottom: 3px solid var(--primary); display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; }
        .logo { height: 60px; }
        
        nav { display: flex; gap: 15px; flex-wrap: wrap; }
        nav a { color: var(--primary); font-weight: bold; font-size: 0.9rem; text-transform: uppercase; }
        
        .hero { 
            height: 400px; 
            background: linear-gradient(rgba(22, 45, 61, 0.7), rgba(22, 45, 61, 0.7)), url('/assets/Exposicion%20Mujres%20Matem%C3%A1ticas_JPG.jpg');
            background-size: cover;
            background-position: center;
            display: flex;
            align-items: center;
            justify-content: center;
            color: var(--white);
            text-align: center;
            padding: 20px;
        }

        .container { max-width: 1100px; margin: 0 auto; padding: 40px 20px; }
        
        .grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 20px; margin-top: 30px; }
        .card { background: var(--white); border: 1px solid #ddd; padding: 15px; border-radius: 8px; box-shadow: 0 4px 6px rgba(0,0,0,0.1); }
        .card img { width: 100%; height: 200px; object-fit: cover; border-radius: 4px; }
        
        footer { background: var(--primary); color: var(--white); text-align: center; padding: 40px; margin-top: 40px; }

        @media (max-width: 768px) {
            nav { flex-direction: column; align-items: center; }
            .hero { height: 250px; }
        }