$(document).ready(function(){

$("#countdown").countdown("06/11/2016 10:00:00", function(event) {

$(this).text(

event.strftime('%D:%H:%M:%S')

);

});

var $mainNavLinks = $('#main-nav a');

$('a[href^="/#"]').on('click', function (e) {

e.preventDefault();

$(document).off("scroll");

if($(e.target).closest('#main-nav').length) {

$mainNavLinks.each(function () {

$(this).removeClass('active');

})

$(this).addClass('active');

}

var target = this.hash,

menu = target;

$target = $(target);

$('html, body').stop().animate({

'scrollTop': $target.offset().top

}, 500, 'swing', function () {

window.location.hash = target;

$(document).on("scroll", onScroll);

});

});

var running = 0;

function onScroll(event){

var scrollPos = $(document).scrollTop();

var headerHeight = $('header').height();

var $mainNav = $('#main-nav');

var mainNavHeight = $mainNav.height();

var $mainNavLinks = $('#main-nav a');

if(scrollPos > headerHeight) {

if(!$mainNav.hasClass('fixed')) {

$mainNav.addClass('fixed').css('top', (-1) * mainNavHeight);

$mainNav.stop().animate({

'top':0

}, 150, 'swing');

}

} else if($mainNav.hasClass('fixed')) {

if(running != 1) {

running = 1;

$mainNav.stop().animate({

'top':(-1) * mainNavHeight

}, 150, 'swing', function() {

$mainNav.removeClass('fixed').css('top', 0);

running = 0;

});

}

}

$mainNavLinks.each(function () {

var currLink = $(this);

var refElement = $('#' + currLink.data("target"));

if (refElement.position().top <= scrollPos + 1 && refElement.position().top + refElement.height() > scrollPos + 1) {

$mainNavLinks.removeClass("active");

currLink.addClass("active");

} else {

currLink.removeClass("active");

}

});

}

$(document).on("scroll", onScroll);

});