BS5 Basic hover

code.html

<nav class="navbar navbar-expand-lg navbar-dark bg-primary">
 <div class="container-fluid">
  <a class="navbar-brand" href="#">Brand</a>
  <button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#main_nav"  aria-expanded="false" aria-label="Toggle navigation">
      <span class="navbar-toggler-icon"></span>
  </button>
  <div class="collapse navbar-collapse" id="main_nav">
	<ul class="navbar-nav">
		<li class="nav-item active"> <a class="nav-link" href="#">Home </a> </li>
		<li class="nav-item"><a class="nav-link" href="#"> About </a></li>
		<li class="nav-item"><a class="nav-link" href="#"> Services </a></li>
		<li class="nav-item dropdown">
		   <a class="nav-link  dropdown-toggle" href="#" data-bs-toggle="dropdown">  Hover me  </a>
		    <ul class="dropdown-menu">
			  <li><a class="dropdown-item" href="#"> Submenu item 1</a></li>
			  <li><a class="dropdown-item" href="#"> Submenu item 2 </a></li>
			  <li><a class="dropdown-item" href="#"> Submenu item 3 </a></li>
		    </ul>
		</li>
	</ul>
  </div> <!-- navbar-collapse.// -->
 </div> <!-- container-fluid.// -->
</nav>

style.css

/* ============ desktop view ============ */
@media all and (min-width: 992px) {
	.navbar .nav-item .dropdown-menu{ display: none; }
	.navbar .nav-item:hover .nav-link{   }
	.navbar .nav-item:hover .dropdown-menu{ display: block; }
	.navbar .nav-item .dropdown-menu{ margin-top:0; }
}	
/* ============ desktop view .end// ============ */

Wonderful