view/index.html

<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="utf-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1">

    <title>DNS Manager</title>

    <meta name="description" content="DNS Manager">
    <meta name="author" content="Kroy">
         <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous">
     <script src="https://code.jquery.com/jquery-3.4.1.min.js" integrity="sha256-CSXorXvZcTkaix6Yvo6HppcZGetbYMGWSFlBw8HfCJo=" crossorigin="anonymous"></script>
     <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>


  </head>
  <body>

    <div class="container-fluid body-content">
	<div class="row">
		<div class="col-md-12">
			<nav class="navbar navbar-default" role="navigation">
				
				<div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1">
					<ul class="nav navbar-nav">
                        <li class="<?php if ($tab=='dns') echo 'active'; ?>">
							<a href="/dns">DNS</a>
						</li>
					</ul>
				</div>
				
			</nav>
            <?php require_once("{$tab}.html") ?>
		</div>
	</div>
</div>

  </body>
</html>