CODE EXAMPLE FOR CSS

nav bar in bootstrap

<nav class="navbar navbar-expand-md navbar-dark bg-dark">
      <div class="container">
          <a href="#" class="navbar-brand">brand</a>
          <button class="navbar-toggler bg-white" data-bs-toggle="collapse" data-bs-target="#nav">
            <span class="navbar-toggler-icon"></span>
          </button>
          <div class="collapse navbar-collapse" id="nav">
            <ul class="navbar-nav">
              <li class="nav-item"><a href='#' class="nav-link">Home</a></li>
              <li class="nav-item"><a href='#' class="nav-link">Support</a></li>
            </ul>
          </div>
     </div>
 </nav>