How to change all-day panel background color in Flutter Calendar?

child: SfCalendar(
  allowedViews: const [CalendarView.day,CalendarView.workWeek,CalendarView.week],
  timeSlotViewSettings: const TimeSlotViewSettings(allDayPanelColor: Colors.deepPurple),
  dataSource: _getCalendarDataSource(),
  view: CalendarView.day,
)
 
_DataSource _getCalendarDataSource() {
  List<Meeting> appointments = <Meeting>[];
  appointments.add(Meeting(
      from: DateTime.now(),
      to: DateTime.now().add(const Duration(minutes: 20)),
      content: 'Meeting',
      background: Colors.greenAccent,
      isAllDay: true
  ));
  appointments.add(Meeting(
    from: DateTime.now().add(const Duration(days: 1)),
    to: DateTime.now().add(const Duration(hours: 2, days: 1)),
    content: 'Planning',
    background: Colors.deepPurple,
  ));
 
  appointments.add(Meeting(
    from: DateTime.now().add(const Duration(days: -2, hours: 2)),
    to: DateTime.now().add(const Duration(hours: 3, days: -2)),
    content: 'Retrospective',
    background: Colors.amber,
  ));
 
  appointments.add(Meeting(
      from: DateTime.now().add(const Duration(days: -5, hours: 2)),
      to: DateTime.now().add(const Duration(hours: 3, days: -5)),
      content: 'Anniversary',
      background: Colors.green,
      isAllDay: true));
 
  appointments.add(Meeting(
    from: DateTime.now().add(const Duration(days: -2, hours: 5)),
    to: DateTime.now().add(const Duration(hours: 6, days: -2)),
    content: 'Sprint planning',
    background: Colors.red,
  ));
 
  return _DataSource(appointments);
}