:root {
    --primary: #4361ee;
    --accent: #4cc9f0;
    --dark: #2b2d42;
    --bg: #f8f9fa;
}

body { font-family: 'Outfit', sans-serif; margin: 0; background-color: var(--bg); color: var(--dark); }

.hero {
    background: linear-gradient(45deg, var(--primary), var(--accent));
    color: white;
    padding: 100px 20px;
    text-align: center;
}

.container { max-width: 1100px; margin: auto; padding: 50px 20px; }

.section-title { text-align: center; margin-bottom: 40px; font-size: 2.5rem; }

.grid-niveles {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
}

.card {
    background: white;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: 0 10px 30px rgba(0,0,0,0.08);
    transition: 0.3s;
}

.card:hover { transform: translateY(-10px); }

.card-info { padding: 25px; text-align: center; }

.btn {
    display: inline-block;
    padding: 12px 25px;
    background: var(--primary);
    color: white;
    text-decoration: none;
    border-radius: 30px;
    font-weight: bold;
    transition: 0.3s;
}

.btn:hover { background: var(--dark); }

.retos-section { background: var(--dark); color: white; padding: 60px 20px; text-align: center; }

.btn-reto {
    padding: 15px 35px;
    background: var(--accent);
    border: none;
    border-radius: 30px;
    font-weight: bold;
    cursor: pointer;
}