/* When the user scrolls down, hide the navbar. When the user scrolls up, show the navbar */
$(document).ready(function() {
    var instance = $('body').overlayScrollbars(); 
    var prevScrollpos = instance.scroll().position.y;

    console.log(prevScrollpos);

    window.onscroll = function() {

        var currentScrollPos = instance.scroll().position.y;
        console.log(currentScrollPos);
        if (prevScrollpos > currentScrollPos) {
                $("#header").css({"top" : "0"});
        } else {
                $("#header").css({"top" : "-50px"});
        }

        prevScrollpos = currentScrollPos;
    }

});