JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://code.jquery.com/jquery-1.12.3.min.js"></script>
<a href="http://searchengines.guru/showthread.php?t=933508" id="downbutton" download="search">Download</a>
<div class="b-popup" id="popup1">
    <div class="b-popup-content">
        Text in Popup
        <a id="hidePopup" onclick="javascript:$(this).parent().parent().hide();" href="#">Скрыть</a>
    </div>
</div>

CSS

*{
    font-family: Areal;
}
.b-container{
    width:200px;
    height:150px;
    background-color: #ccc;
    margin:0px auto;
    padding:10px;
    font-size:30px;
    color: #fff;
}
.b-popup{
    width:100%;
    min-height:100%;
    background-color: rgba(0,0,0,0.5);
    overflow:hidden;
    position:fixed;
    top:0px;
}
.b-popup .b-popup-content{
    margin:40px auto 0px auto;
    width:100px;
    height: 40px;
    padding:10px;
    background-color: #c5c5c5;
    border-radius:5px;
    box-shadow: 0px 0px 10px #000;
}

JavaScript

function PopUpShow(){
   $("#popup1").show();
}

$(document).ready( function(){
 $("#popup1").hide();
 $('#downbutton').click(function(){
 	PopUpShow();
 });
 
});