how to create a large rectangle on landing page using bootstrap
<!-- navbar -->
<nav class="navbar navbar-expand-lg fixed-top ">
<a class="navbar-brand" href="#">Home</a>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse " id="navbarSupportedContent"> <ul class="navbar-nav mr-4">
<li class="nav-item">
<a class="nav-link" data-value="about" href="#">About</a> </li>
<li class="nav-item">
<a class="nav-link " data-value="portfolio"href="#">Portfolio</a>
</li>
<li class="nav-item">
<a class="nav-link " data-value="blog" href="#">Blog</a> </li>
<li class="nav-item">
<a class="nav-link " data-value="team" href="#"> Team</a> </li>
<li class="nav-item">
<a class="nav-link " data-value="contact" href="#">Contact</a> </li>
</ul>
</div></nav>