<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css"> <script src="//maxcdn.bootstrapcdn.com/bootstrap/4.1.1/js/bootstrap.min.js"></script> <script src="//cdnjs.cloudflare.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script> <!------ Include the above in your HEAD tag ----------> <div class="container"> <div class="row"> <button onclick="loadit()">Test</button> <div id="modal" class="myModal hidden"> <p>Hi</p> </div> </div> </div>

.myModal:shown { width: 100px; height: 100px; } .myModal:shown { transition: color 4s ease-in; transition-delay: 4s; visibility: visible; } .hidden { visibility: hidden; }

function loadit() { var item = document.querySelector("#modal"); item.className = "myModal shown"; }