<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>
<!DOCTYPE html>
<html>
<head>
<title>G-mail Animation</title>
<meta charset="utf-8">
<link rel="stylesheet" type="text/css" href="style.css">
<style>*{
margin: 0;
padding: 0;
font-family: arial;
}
body{
margin: 0;
padding: 0;
text-align: center;
}
.container{
width: 100%;
height: 100%;
position: relative;
}
.box1{
width: 170px;
height: 125px;
position: absolute;