body {
    font-family: Arial, sans-serif;
    background: linear-gradient(to bottom, #0066cc, #ffcc00);
    color: #fff;
    margin: 0;
    padding: 0;
}

header {
    background: #003399;
    padding: 10px;
    text-align: center;
}

header nav a {
    color: #ffcc00;
    margin: 0 10px;
    text-decoration: none;
}

main {
    padding: 20px;
    text-align: center;
}

ul {
    list-style: none;
    padding: 0;
}

ul li {
    background: #0044cc;
    margin: 10px;
    padding: 10px;
    border-radius: 5px;
}