JSFiddle - React, Tailwind, and code Playground

HTML

<html>
    <head>
        <link rel="stylesheet" href="http://code.jquery.com/mobile/1.0/jquery.mobile-1.0.min.css" />
        
<style>
.modalWindow{
    width: 100%;
    height: 100%;
    position: absolute;
    z-index: 1500;
    background: white;
    opacity: 0.7;
}

.ui-loader{
    z-index: 1501;
}
        </style>
<script src="http://code.jquery.com/jquery-1.6.4.min.js"></script>
<script src="http://code.jquery.com/mobile/1.0/jquery.mobile-1.0.min.js"></script>
<script>
function showModal(){
  $("body").append('<div class="modalWindow"/>');
  $.mobile.showPageLoadingMsg();
  setTimeout('hideModal()', 2000);
}

function hideModal(){
 $(".modalWindow").remove();
  $.mobile.hidePageLoadingMsg();

}

</script>

    </head>
        <body>
        <div data-role="page">
            <div data-role="header" data-position="fixed">
                <h1>Header</h1>
            </div>
            <div data-role="content">
                <input type="button" value="Click to show modal loading window" onclick="showModal()"/>
            </div>
            <div data-role="footer" data-position="fixed">
                <h1>Footer</h1>
            </div>
            
        </div>
          
        </body> 
</html>