body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    color: #333;
    margin: 0;
    padding: 0;
    line-height: 1.0;
}

header {
    background-color: #007BFF;
    color: white;
    padding: 1rem 0;
    text-align: center;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

main {
    padding: 2rem;
    max-width: 640px;
    margin: 0rem auto;
    background-color: #fff;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

.container {
    display: flex;
    align-items: stretch;
    gap: 10px;
}