JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="https://code.htmlhifive.com/h5.css">
<script src="https://code.htmlhifive.com/ejs-h5mod.js"></script>
<script src="https://hifive.github.io/hifive-res/fw/current/h5.dev.js"></script>
<script src="https://hifive.github.io/hifive-ui-library/hifive-ui-library/WebContent/components/calendar/src/CalendarController.js"></script>
<link rel="stylesheet" href="https://hifive.github.io/hifive-ui-library/hifive-ui-library/WebContent/components/calendar/src/CalendarController.css">
<div id="container"></div>
<p>
  <button id="marker">マーカーをつける</button>
</p>

JavaScript

$(function(){
  var disableDates = [];
	var mainController = {
		__name : 'h5.ui.container.MainController',
		calendarController: h5.ui.components.Calendar,
		__meta : {
			calendarController: {
				rootElement: '#container'
			},
		},

		__init: function(){
    	this.$find(".select:first").attr("checked", true);
		},
    
    '#marker click': function(context, $el) {
      var dates = this.calendarController.getSelectedDate();
      for (var i=0; i<dates.length; i++) {
				this.calendarController.setMarker(dates[i], true);
			}
    },
};

	h5.core.controller('body', mainController);

});