var menu = document.querySelector('.nav__list');
var burger = document.querySelector('.burger');
var doc = $(document);
var l = $('.scrolly');
var panel = $('.panel');
var vh = $(window).height();

var openMenu = function() {
  burger.classList.toggle('burger--active');
  menu.classList.toggle('nav__list--active');
};

// reveal content of first panel by default
panel.eq(0).find('.panel__content').addClass('panel__content--active');

var scrollFx = function() {
  var ds = doc.scrollTop();
  var of = vh / 4;
  
  // if the panel is in the viewport, reveal the content, if not, hide it.
  for (var i = 0; i < panel.length; i++) {
    if (panel.eq(i).offset().top < ds+of) {
     panel
       .eq(i)
       .find('.panel__content')
       .addClass('panel__content--active');
    } else {
      panel
        .eq(i)
        .find('.panel__content')
        .removeClass('panel__content--active')
    }
  }
};

var scrolly = function(e) {
  e.preventDefault();
  var target = this.hash;
  var $target = $(target);

  $('html, body').stop().animate({
      'scrollTop': $target.offset().top
  }, 300, 'swing', function () {
      window.location.hash = target;
  });
}

var init = function() {
  burger.addEventListener('click', openMenu, false);
  window.addEventListener('scroll', scrollFx, false);
  window.addEventListener('load', scrollFx, false);
  $('a[href^="#"]').on('click',scrolly);
};

doc.on('ready', init);

@@ -1411,12 +1411,631 @@
 dy', init);%0A
+%0A%0A%0A%0Awindow.ChatraSetup = %7B%0A    mode: 'frame',%0A    injectTo: 'chatra-wrapper' %0A%7D;%0A    ChatraID = 'tBXJTuu2psNABNcC2';%0A    (function(d, w, c) %7B%0A        var n = d.getElementsByTagName('script')%5B0%5D,%0A            s = d.createElement('script');%0A        w%5Bc%5D = w%5Bc%5D %7C%7C function() %7B%0A            (w%5Bc%5D.q = w%5Bc%5D.q %7C%7C %5B%5D).push(arguments);%0A        %7D;%0A        s.async = true;%0A        s.src = (d.location.protocol === 'https:' ? 'https:': 'http:')%0A            + '//call.chatra.io/chatra.js';%0A        n.parentNode.insertBefore(s, n);%0A    %7D)(document, window, 'Chatra');%0A%09%0A%09   Chatra('setColors', %7B%0A    chatBg: 'transparent' // %D1%84%D0%BE%D0%BD%0A%7D);%0A

Update index.js