document.addEventListener('DOMContentLoaded', function() {
  if (!document.querySelector('.blog_page')) return;
/* 2.2 Blog page fixed header */
if($('.main').hasClass('blog_page')){
    var header = $('.header');
	var classes = 'active';
	var headerHeight = header.outerHeight();
	var scroll = $(window).scrollTop();
	var isScroll = false;

	$(window).on('scroll', function() {
		scroll = $(window).scrollTop();

		if (scroll >= headerHeight) {
			isScroll = true;
			headerHeight = isScroll ? header.outerHeight() : null;
			header.addClass(classes);

			if (!header.hasClass('is-fixed')) {
				header.css({'top': -headerHeight + 'px', 'transform': 'translateY(' + headerHeight + 'px)'}).addClass('is-fixed');
			}
		} else {
			isScroll = false;
			header.removeClass(classes + ' is-fixed').removeAttr('style');
		}
	});
    
}


/* 2.3 Noise animation */
});