<link href="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" rel="stylesheet" id="bootstrap-css">
<script src="//maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
<script src="//code.jquery.com/jquery-1.11.1.min.js"></script>
<!------ Include the above in your HEAD tag ---------->
<div class="container me">
<div class="row">
<header>
<div id="topbar" class="fixed-top clearHeader">
<div class="container">
<div class="row">
<div class="col-sm-12">
<nav class="navbar navbar-expand-lg navbar-dark">
<a class="navbar-brand" href="#">Logo</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 ml-auto mr-3">
<li class="nav-item active">
<a class="nav-link text-uppercase" href="#">Home <span class="sr-only">(current)</span></a>
</li>
<li class="nav-item">
<a class="nav-link text-uppercase" href="#">About</a>
</li>
<li class="nav-item">
<a class="nav-link text-uppercase" href="#">Apps</a>
</li>
<li class="nav-item">
<a class="nav-link text-uppercase" href="#">subscription</a>
</li>
<li class="nav-item">
<a class="nav-link text-uppercase" href="#">contact us</a>
</li>
<li class="nav-item">
<a class="nav-link text-uppercase" href="#">mini desert</a>
</li>
</ul>
<button type="button" class="btn btn-link">Login/Register</button>
</div>
</nav>
</div>
</div>
</div>
</div>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p><p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p>
<p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p><p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p><p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p><p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p><p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p><p>Lorem ipsum dolor sit amet, consectetur adipiscing elit. Sed lobortis pretium enim, ut accumsan ligula faucibus eget. Proin et lobortis orci, at vestibulum nisi. Pellentesque consectetur mollis...</p>
</header>
</div>
</div>
.me {
background-color:orange;
}
header .bg-black {
background-color:#000;
transition:1s;
}
header #topbar .navbar-brand {
font: 400 42px/54px open sans;
}
header #topbar .nav-link {
color: #fff;
}
header #topbar .nav-link:hover {
color:#ed6806;
}
p {
margin: 80px 0 0 0;
}
$(function() {
var header = $(".clearHeader");
$(window).scroll(function() {
var scroll = $(window).scrollTop();
if (scroll >= 100) {
header.removeClass('clearHeader').addClass("bg-black");
} else {
header.removeClass("bg-black").addClass('clearHeader');
}
});
});