body {
    font-family: Arial, sans-serif;
    background: #f3f3f3;
    margin: 0;
}

header {
    background: #111;
    color: white;
    padding: 20px;
}

main {
    padding: 30px;
}

footer {
    background: #222;
    color: white;
    padding: 20px;
}