JSFiddle - React, Tailwind, and code Playground

HTML

<div id="loadingDiv">
    <div>
        <h7>Please wait...</h7>
    </div>
</div>
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CSS

#loadingDiv{position:fixed;top:0px;right:0px;width:100%;height:100%;background-color:#666;background-image:url('http://pulse.sindlab.com.pk//images/ajax-loading.gif'); background-repeat:no-repeat;background-position:center;z-index:10000000;  opacity: 0.4;
filter: alpha(opacity=40); /* For IE8 and earlier */}