<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 d-flex flex-row justify-content-center mt-5"> <div class="col-lg-5"> <div class="card"> <div class="card-body"> <form method="POST" action=""> <div class="form-group"> <input type="text" name="username" class="form-control" placeholder="username"> </div> <div class="form-group"> <input type="password" name="password" class="form-control" placeholder="password"> </div> <div class="form-group"> <button class="btn btn-primary btn-lg btn-block"> login </button> </div> </form> </div> </div> </div> </div> </div>