admin calender(weekAgenda)

Hi, I’m trying to customize admin-calender for limited hours.

in fullcalender.js(and fullcalender.min.js),

setDefaults({
	allDaySlot: false,
	allDayText: 'all-day',
	scrollTime: '11:00:00',
	slotDuration: '00:30:00',
	minTime: '11:00:00',
	maxTime: '20:00:00',
	slotEventOverlap: true
});

so the following calender is displayed.

I want to delete the below blank and change the height of each line.what should I do?