index.html

<!doctype html>
<html lang="en">
  <head>
    <!-- Required meta tags -->
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
   

    <!-- Bootstrap CSS -->

    <link rel="stylesheet" href="stye.css">

    <title>Number Counter</title>
  </head>
  <body>


     <main>
         
     <div class="container">
    
        <h1>COUNTER</h1>
     </div>
     <span id="value">0</span>
     <div class="button-container">

        <button class="btn decrease">Decrease</button>
        <button class="btn reset">reset</button>
        <button class="btn increase ">Increase</button>
     </div>
     

     </main>

      </div>


      <script src="app.js"></script>
    

    <!-- Optional JavaScript -->
    <!-- jQuery first, then Popper.js, then Bootstrap JS -->
  
  </body>
</html>