.calendar { width: 100%; } 
.calendar-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 5px; } 
.calendar-header button { background: #0074e0; border: none; color: #fff; padding: 5px 10px; cursor: pointer; border-radius: 4px; } 
.calendar-header span { font-weight: bold; } 
.calendar table { width: 100%; border-collapse: collapse; text-align: center; font-size: 14px; }
.calendar th,
.calendar td { padding: 6px; height: 30px; } 
.calendar td.active { background: #0074e0; color: #fff; border-radius: 4px; font-weight: bold; }