<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<title>Nav</title>
<style>
a.active
{
background:#000000;
color:#ffffff;
}
</style>
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
</head>
<body>
<div >
<ul>
<li class="active-class"><a href="#" class="active">home</a></li>
<li class="active-class"><a href="#">about</a></li>
<li class="active-class"><a href="#">gallery</a></li>
<li class="active-class"><a href="#">contact us</a></li>
</ul>
</div>
<script>
$(document).ready(function(){
$(".active-class a").click(function() {
$(".active-class a").removeClass("active");
$(this).addClass("active");
});
});
</script>
</body>
</html>