Navbar

<nav class="navbar navbar-expand-xl navbar-light bg-light py-0">
  <div class="container-fluid">
    <a class="navbar-brand" href="#">Navbar</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#nav1" aria-controls="nav1" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="nav1">
      <ul class="navbar-nav me-auto">
        <li class="nav-item"><a class="nav-link active" href="#">Home <span class="sr-only">(current)</span></a></li>
        <li class="nav-item dropdown">
          <a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown" aria-haspopup="true" aria-expanded="false" id="dropdown1">Dropdown</a>
          <div class="dropdown-menu" aria-labelledby="dropdown1">
            <a class="dropdown-item" href="#">Action</a>
            <a class="dropdown-item" href="#">Another action</a>
            <a class="dropdown-item" href="#">Something else here</a>
          </div>
        </li>
      </ul>
      <form class="d-flex">
        <input class="form-control form-control-sm me-sm-2" type="search" placeholder="Search" aria-label="Search" />
        <button class="btn btn-sm my-2 my-sm-0 btn-outline-secondary" type="submit">Search</button>
      </form>
    </div>
  </div>
</nav>

<nav class="navbar navbar-expand-xl navbar-dark bg-dark py-0">
  <div class="container-fluid">
    <a class="navbar-brand fw-normal ls-2" href="/">RE<span class="navbar-brand-i">!</span>GN</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#nav2" aria-controls="nav2" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="nav2">
      <ul class="navbar-nav me-auto">
        <li class="nav-item"><a class="nav-link active" href="#">Home <span class="sr-only">(current)</span></a></li>
        <li class="nav-item dropdown">
          <a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown" aria-haspopup="true" aria-expanded="false" id="dropdown2">Dropdown</a>
          <div class="dropdown-menu" aria-labelledby="dropdown2">
            <a class="dropdown-item" href="#">Action</a>
            <a class="dropdown-item" href="#">Another action</a>
            <a class="dropdown-item" href="#">Something else here</a>
          </div>
        </li>
      </ul>
      <form class="d-flex">
        <input class="form-control form-control-sm me-sm-2" type="search" placeholder="Search" aria-label="Search" />
        <button class="btn btn-sm my-2 my-sm-0 btn-outline-secondary" type="submit">Search</button>
      </form>
    </div>
  </div>
</nav>

<nav class="navbar navbar-expand-xl navbar-dark bg-primary py-0">
  <div class="container-fluid">
    <a class="navbar-brand fw-normal ls-2" href="/">RE<span class="navbar-brand-i">!</span>GN</a>
    <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#nav3" aria-controls="nav3" aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
    </button>
    <div class="collapse navbar-collapse" id="nav3">
      <ul class="navbar-nav me-auto">
        <li class="nav-item"><a class="nav-link active" href="#">Home <span class="sr-only">(current)</span></a></li>
        <li class="nav-item dropdown">
          <a class="nav-link dropdown-toggle" href="#" role="button" data-bs-toggle="dropdown" aria-haspopup="true" aria-expanded="false" id="dropdown3">Dropdown</a>
          <div class="dropdown-menu" aria-labelledby="dropdown3">
            <a class="dropdown-item" href="#">Action</a>
            <a class="dropdown-item" href="#">Another action</a>
            <a class="dropdown-item" href="#">Something else here</a>
          </div>
        </li>
      </ul>
      <form class="d-flex">
        <input class="form-control form-control-sm me-sm-2" type="search" placeholder="Search" aria-label="Search" />
        <button class="btn btn-sm my-2 my-sm-0 btn-outline-light" type="submit">Search</button>
      </form>
    </div>
  </div>
</nav>