JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://arshaw.com/js/fullcalendar-1.5.3/fullcalendar/fullcalendar.css">
<script src="http://www.arshaw.com/js/fullcalendar-1.5.3/fullcalendar/fullcalendar.min.js"></script>
<script src="http://arshaw.com/js/fullcalendar-1.5.4/fullcalendar/gcal.js"></script>
<div style="border:solid 2px red;">
    <div id='calendar'></div>
</div>

CSS

.fc-widget-content-custom {
    position: absolute;
}
.fc-day-number-custom {
    position: absolute;
    right: 0;
    bottom: 0;
}

JavaScript

$(document).ready(function () {
    $('#calendar').fullCalendar({
        header: {
            left: 'prev,next today',
            center: 'title',
            right: 'month,agendaWeek,agendaDay'
        }
    });

    $('.fc-widget-content').addClass('fc-widget-content-custom');
    $('.fc-day-number').addClass('fc-day-number-custom');
});