Answers for "button in navbar bootstrap"

bootstrap navbar fixed top

<section id="headnev" class="navbar navbar-fixed-top">

bootstrap navbar

<nav class="navbar navbar-dark bg-dark">
  <!-- Navbar content -->
</nav>

<nav class="navbar navbar-dark bg-primary">
  <!-- Navbar content -->
</nav>

<nav class="navbar navbar-light" style="background-color: #e3f2fd;">
  <!-- Navbar content -->
</nav>