body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f4f4f4;
    color: #333;
}
header {
    background: #008080;
    color: white;
    padding: 20px;
    text-align: center;
}
main {
    padding: 20px;
    max-width: 800px;
    margin: auto;
}
footer {
    background: #222;
    color: white;
    text-align: center;
    padding: 10px;
    margin-top: 20px;
}