JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.8/themes/dot-luv/jquery-ui.css">
<button>Add Popup</button>
Content<br />
Content<br />

CSS

.popup {
      background-color:#fff;
      border:solid 10px #AE0000;
      -webkit-box-shadow:2px 2px 5px #000;
      -moz-box-shadow:2px 2px 5px #000;
      box-shadow:2px 2px 5px #000;
      z-index:1;
      display:none;
      position:absolute;
      padding:15px;
    }

JavaScript

$("button").click(function() {
    $("<div />", {"class":"popup", text: "This is a popup"}).insertAfter(this).fadeIn();
});