 <link href="navbar.css" rel="stylesheet">
  </head>

  <body>

    <nav class="navbar navbar-dark bg-dark">
      <a class="navbar-brand" href="#">Never expand</a>
      <button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarsExample01" aria-controls="navbarsExample01" aria-expanded="false" aria-label="Toggle navigation">
        <span class="navbar-toggler-icon"></span>
      </button>

      <div class="collapse navbar-collapse" id="navbarsExample01">
        <ul class="n