Here's a minimal example: (the js links are from bootstrap, https://getbootstrap.com/docs/4.4/getting-started/download/ you can recopy-paste them if you don't trust them).
body {
background-color: black;
}
#nav {
background-color: blue;
margin: 0;
padding: 0;
height: fit-content;
}
#nav a {
background-color: white;
height: 75px;
}
<html>
<head>
<script src="https://code.jquery.com/jquery-3.4.1.slim.min.js" integrity="sha384-J6qa4849blE2+poT4WnyKhv5vZF5SrPo0iEjwBvKU7imGFAV0wwj1yYfoRSJoZ+n" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/popper.js@1.16.0/dist/umd/popper.min.js" integrity="sha384-Q6E9RHvbIyZFJoft+2mJbHaEWldlvI9IOYy5n3zV9zzTtmI3UksdQRVvoxMfooAo" crossorigin="anonymous"></script>
<link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css" integrity="sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh" crossorigin="anonymous">
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/js/bootstrap.min.js" integrity="sha384-wfSDF2E50Y2D1uUdj0O3uMBJnjuUD4Ih7YwaYd1iqfktj0Uod8GCExl3Og8ifwB6" crossorigin="anonymous"></script>
</head>
<body>
<div id="nav" class="navbar fixed-bottom nav-fill">
<a class="nav-item nav-link" href="#">test</a>
</div>
</body>
</html>
The reason I want the to be big and the text in the center of it is because I want to change the background color of it when the user hovers over it and also when the mouse is down on the link, so covering it in a isn't an option. Thanks!