 <div class="row footer">
   <div class="col text-center">
     <hr>
     </hr>
     <a href="contact_us.php">Contact Us</a>
   </div>
 </div>
 <!-- penutup footer -->

 <!-- Optional JavaScript -->
 <!-- jQuery first, then Popper.js, then Bootstrap JS -->
 <script src="js/jquery-3.4.1.slim.min.js"></script>
 <script src="js/popper.min.js"></script>
 <script src="js/bootstrap.min.js"></script>
 </body>

 </html>