body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
}

header {
    background: #333;
    color: #fff;
    padding: 10px 0;
    text-align: center;
}

nav {
    margin: 15px 0;
}

nav a {
    color: #fff;
    margin: 0 15px;
    text-decoration: none;
}

section {
    padding: 20px;
}

footer {
    text-align: center;
    padding: 10px 0;
    background: #333;
    color: #fff;
    position: fixed;
    width: 100%;
    bottom: 0;
}

@media (max-width: 600px) {
    nav a {
        display: block;
        margin: 5px 0;
    }
}