body {
    font-family: Arial, sans-serif;
    background-color: #f9f9f9;
    margin: 0;
    padding: 0;
}

header {
    background-color: #4CAF50;
    color: white;
    text-align: center;
    padding: 20px 0;
}

.main-content {
    max-width: 800px;
    margin: 20px auto;
    padding: 20px;
    background-color: #f5f5f5;
    border-radius: 5px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

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