<div class="col-md-6 col-md-offset-3"> <nav class="navbar navbar-default"> <div class="collapse navbar-collapse" id="bs-example-navbar-collapse-1"> <ul class="nav navbar-nav"> <li <?php if(!isset($_GET['admin'])) echo 'class="active"'; ?>><a href="index.php">Configurations</a></li> <li <?php if(isset($_GET['admin'])) echo 'class="active"'; ?>><a href="index.php?admin">Administrator</a></li> </ul> </div> </nav> </div>