JSFiddle - React, Tailwind, and code Playground

HTML

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 <title></title>
    <link href="http://www.malsup.com/jquery/block/ui/jquery-ui-1.7.2.redmond.css" rel="stylesheet" type="text/css" />

   <script src="http://malsup.com/jquery/block/jquery.blockUI.js?v2.38" type="text/javascript"></script>

    <script language="javascript" type="text/javascript">

        $(document).ready(function() {

            bindCalerdar();
        
            $('#btnTest').click(function() {
                
                $.blockUI({ message: $('#divAddNew'), css: { border: '0', width: '200px', height: '200px'} });
            });
        
            $('#btnCancel').click(function(){
                $.unblockUI();
            });
        });


        // Bind Calerdar
        function bindCalerdar() {

            $(".calerdar").datepicker({
                showOn: "button",
                buttonText: 'Edit',
                dateFormat: 'yy/mm/dd',
                changeMonth: true,
                changeYear: true,
                showButtonPanel: true,
                closeText: 'Clear'
            });
        }
        
        
    </script>
    <style  type="text/css">
        .ui-datepicker{width:16em;}
        .ui-datepicker TH {padding-top:0.4em;padding-bottom:0.4em;}
        .ui-datepicker table {font-size:0.85em; margin-bottom:0.2em;}
        .ui-datepicker .ui-datepicker-buttonpane{margin-top:0.4em;}
        .ui-datepicker .ui-datepicker-buttonpane button{padding-left:0.4em;padding-right:0.4em; font-size:0.85em;}
        
        #ui-datepicker-div{z-index:1013; font-size:14px;}
        
        .ui-datepicker .ui-datepicker-header{z-index:1014;}
        .ui-datepicker-calendar{z-index:1014;}
        
        .ui-datepicker .ui-datepicker-title{z-index:1015;}
        
       ...