body {
    font-family: Arial, sans-serif;
    margin: 20px;
}

header {
    background-color: #f0f0f0;
    padding: 10px;
    text-align: center;
}

main {
    margin-top: 20px;
}

table {
    width: 100%;
    border-collapse: collapse;
}

th, td {
    border: 1px solid #ccc;
    padding: 8px;
    text-align: left;
}

th {
    background-color: #4CAF50;
    color: white;
}

.error {
    color: red;
}