FullCalendar with resourceTimeline draggable events

let calendarEl = document.getElementById(‘calendar’);

let calendar = new FullCalendar.Calendar(calendarEl, {
plugins: [‘interaction’, ‘resourceTimeline’],

with var Draggable = FullCalendarInteraction.Draggable;

my events Draggable have start and end date

like number 7 in this image

my work
change background color to lightgreen

how at move event above Calendar read start and end date
then the duration from 2 dates changes the background color of the Calendar
just duration and above Calendar ?