* {
    box-sizing: border-box;
    font-family: Arial, sans-serif;
}

body {
    margin: 0;
    background-color: #f4f4f4;
}

header {
    background-color: #003366;
    color: white;
    padding: 15px;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 15px;
    padding: 0;
}

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

main {
    padding: 20px;
}

section {
    background: white;
    margin-bottom: 20px;
    padding: 15px;
    border-radius: 8px;
}

.imagen-responsive {
    max-width: 100%;
    height: auto;
}

footer {
    background-color: #003366;
    color: white;
    text-align: center;
    padding: 10px;
}