How to change the allDayPanel height in day view of SfCalendar?

Question

I use appointmentBuilder and changed color etc. but, the height was not changed.

enter image description here

             SfCalendar(
                view: CalendarView.day,
                dataSource: TestDataSource(controller.tests.value),
                onViewChanged: (ViewChangedDetails details) {
                },
                initialDisplayDate: _initialDate,
                headerHeight: 0,
                todayHighlightColor: AppTheme.colorScheme.secondary,
                appointmentBuilder:
                    (BuildContext context, CalendarAppointmentDetails details) {
                  return Container(
                    height: 300,
                    decoration: BoxDecoration(
                      color: details.appointments.first.background,
                      borderRadius: BorderRadius.circular(4),
                    ),
                    child: Text(
                      details.appointments.first.eventName,
                      style: TextStyle(
                        color: AppTheme.colorScheme.primary,
                        fontSize: 12,
                      ),
                    ),
                  );
               },
              ),