https://js03-public.ca-proteine.fr/animatedHeader/cbpAnimatedHeader.js

1/**
2 * cbpAnimatedHeader.js v1.0.0
3 * http://www.codrops.com
4 *
5 * Licensed under the MIT license.
6 * http://www.opensource.org/licenses/mit-license.php
7 *
8 * Copyright 2013, Codrops
9 * http://www.codrops.com
10 */
11var cbpAnimatedHeader = (function() {
12
13    var docElem = document.documentElement,
14        header = document.querySelector( '.navbar-default' ),
15        didScroll = false,
16        changeHeaderOn = 200;
17
18    function init() {
19        window.addEventListener( 'scroll', function( event ) {
20            if( !didScroll ) {
21                didScroll = true;
22                setTimeout( scrollPage, 250 );
23            }
24        }, false );
25    }
26
27    function scrollPage() {
28        var sy = scrollY();
29        if ( sy >= changeHeaderOn ) {
30            classie.add( header, 'navbar-scroll' );
31        }
32        else {
33            classie.remove( header, 'navbar-scroll' );
34        }
35        didScroll = false;
36    }
37
38    function scrollY() {
39        return window.pageYOffset || docElem.scrollTop;
40    }
41
42    init();
43
44})();