Fade-in menu a lá MOIA

@media (min-width:768px) {
#navigation {opacity: 0;}
.menu-helper {opacity: 0;}
#navigation.menu-show {opacity: 1;animation: fadeIn 1s;animation-fill-mode: forwards;}
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}
}

<script>
var doit;
$('#header').bind("DOMSubtreeModified", function() {
clearTimeout(doit);
doit = setTimeout(function() {
console.log('render');
$('#navigation').addClass('menu-show');
$('#header').unbind("DOMSubtreeModified");
}, 200);
});
</script>