body {
    font-family: Arial, sans-serif;
    background-color: #f4f4f4;
    margin: 0;
    padding: 20px;
}

header {
    text-align: center;
    color: #333;
}

#calendar {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 5px;
    background-color: white;
    padding: 10px;
    border-radius: 8px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.date {
    text-align: center;
    padding: 15px;
    background-color: #f9f9f9;
    border-radius: 4px;
}

.today {
    background-color: #e6e6ff;
}