CODE EXAMPLE FOR JAVASCRIPT

slicknav cdn

<link rel="https://cdnjs.cloudflare.com/ajax/libs/SlickNav/1.0.10/slicknav.min.css" />
<script src="https://cdnjs.cloudflare.com/ajax/libs/SlickNav/1.0.10/jquery.slicknav.min.js"></script>

// initialize 
<script>
    $(function(){
        $('#menu').slicknav();
    });
</script>