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

.calendar-container {
    max-width: 1200px;
    margin: 0 auto;
    background-color: white;
    border-radius: 10px;
    padding: 20px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
}

.header {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-bottom: 20px;
}

.header button, .header select {
    background: none;
    border: none;
    font-size: 16px;
    cursor: pointer;
    margin: 0 10px;
}

.header h2 {
    margin: 0 20px;
}

.summary {
    display: flex;
    justify-content: space-around;
    margin-bottom: 20px;
}

.summary-item {
    text-align: center;
}

.summary-item span {
    font-size: 24px;
    font-weight: bold;
    color: #007BFF;
}

.months-container {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
}

.month-card {
    border: 1px solid #ddd;
    border-radius: 5px;
    padding: 10px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.month-card:hover {
    background-color: #f0f0f0;
}

.month-card h3 {
    margin-top: 0;
    text-align: center;
}

.month-info {
    display: flex;
    justify-content: space-between;
    margin-top: 10px;
}

.month-info p {
    font-size: 14px;
    margin: 0;
}

.detailed-view {
    margin-top: 20px;
}

.detailed-header {
    text-align: center;
    margin-bottom: 20px;
}

.detailed-summary {
    display: flex;
    justify-content: space-around;
    margin-bottom: 20px;
}

.detailed-calendar {
    display: grid;
    grid-template-columns: repeat(7, 1fr);
    gap: 1px;
    background-color: #ddd;
    border: 1px solid #ddd;
}

.detailed-calendar-header {
    background-color: #f0f0f0;
    padding: 10px;
    text-align: center;
    font-weight: bold;
}

.day-cell {
    background-color: white;
    padding: 10px;
    min-height: 100px;
    border: 1px solid #eee;
}

.day-number {
    font-weight: bold;
    margin-bottom: 5px;
}

.activity {
    font-size: 12px;
    margin: 2px 0;
    padding: 2px;
    color: #007BFF;
    border-left: 2px solid #007BFF;
}