Full Calendar backgroundColor and borderColor

The evernt border and background color are not equal.

HTML

<script src="https://code.jquery.com/jquery-1.12.3.min.js"></script>
<script src="https://code.jquery.com/ui/1.11.2/jquery-ui.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.9.0/moment.min.js"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/fullcalendar/2.2.6/fullcalendar.min.js"></script>
<link rel="stylesheet" href="https://cdnjs.cloudflare.com/ajax/libs/fullcalendar/2.2.6/fullcalendar.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
<link rel="stylesheet" href="//maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<div id='calendar'></div>

CSS

#calendar {
        width: 100%;
    }

JavaScript

/*--------------------------------*/
    /*          CALENDAR              */
    /*--------------------------------*/
    $(document).ready(function() {
		var today = new Date();
            var dd = today.getDate();
            var mm = today.getMonth() + 1; //January is 0!

            var yyyy = today.getFullYear();
            if (dd < 10) {
                dd = '0' + dd;
            }
            if (mm < 10) {
                mm = '0' + mm;
            }
            var today = yyyy + '-' + mm + '-' + dd;
        
        function getRandomColor() {
            var letters = '0123456789ABCDEF';
            var color = '#';
            for (var i = 0; i < 6; i++) {
                color += letters[Math.floor(Math.random() * 16)];
            }
            return color;
        }

            var genColor =getRandomColor();
		$('#calendar').fullCalendar({

            
			header: {
				left: 'prev,next today',
				center: 'title',
				right: 'month,agendaWeek,agendaDay,listWeek'
			},
			defaultDate: today,
			navLinks: true, // can click day/week names to navigate views
			editable: false,
			eventLimit: true, // allow "more" link when too many events
			events: [
				{
					title: 'Philippine Seven Corporation',
					start: '2017-05-01',                    
                    backgroundColor : getRandomColor()		
                },
				{
					/* title: 'Long Event',
					start: '2017-05-07',
					end: '2017-05-10', */
                   // backgroundColor : genColor,
                   // borderColor : genColor	
				},
				{
					id: 999,
					title: 'Repeating Event',
					start: '2017-05-09T16:00:00',
                    backgroundColor : genColor,
                    borderColor : genColor	
				},
				{
					id: 999,
					title: 'Repeating Event',
					start: '2017-05-16T16:00:00',
                    backgroundColor : genColor,
                    borderColor : genColor	
				},
				{
					title: 'Conference',
					start: '2017-05-11',
					end:...