body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    color: #333;
}

header {
    background-color: #004080;
    color: white;
    padding: 1rem 2rem;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 1.5rem;
}

nav a {
    color: white;
    text-decoration: none;
    font-weight: bold;
}

.contenedor {
    padding: 2rem;
    max-width: 1000px;
    margin: 0 auto;
}

.grid-productos {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.tarjeta-producto {
    border: 1px solid #ddd;
    border-radius: 8px;
    padding: 1rem;
    background: #f9f9f9;
}

.precio {
    display: block;
    font-weight: bold;
    color: #004080;
    margin: 0.5rem 0;
}

.btn {
    display: inline-block;
    background: #004080;
    color: white;
    padding: 0.5rem 1rem;
    text-decoration: none;
    border-radius: 4px;
}

.alerta {
    background-color: #d4edda;
    color: #155724;
    padding: 1rem;
    border-radius: 4px;
    margin-bottom: 1rem;
}