var getScrollItems = function () {
    if (window.innerWidth <= 1025) {
	return $(".sectionBlock:visible");
    }
    return $("section:visible");
};
var scrollItems = getScrollItems();
var animating = false;
var lastScrollTop = 0;
var isUp = 0;
$(document).scroll(function () {
    var st = $(this).scrollTop();
    if (st > lastScrollTop) {
	isUp = 0;
    } else {
	// upscroll code
	isUp = 1;
    }
    lastScrollTop = st;
    clearTimeout($.data(this, 'scrollTimer'));
    if (!animating) {
	$.data(this, 'scrollTimer', setTimeout(function () {
	    var l = scrollItems.length;
	    var i = 0;
	    for (; i < l; i++) {
		if (i === 0) {
		    var item = isUp ? $('header') : scrollItems[i];
		} else {
		    var item = isUp ? scrollItems[i - 1] : scrollItems[i];
		}
		if ($(window).scrollTop() > 0 && $(scrollItems[i]).offset().top > $(window).scrollTop()) {
		    animating = true;
		    $('html, body').animate({scrollTop: $(item).offset().top + 'px'}, 250);
		    setTimeout(function () {
			animating = false;
		    }, 500);
		    return false;
		}
	    }

	}, 200));
    }
});