https://www.gmpopcorn.com/js/gmph.js

1$(document).ready(function () {
2  $(document).on("scroll", onScroll);
3
4  //smoothscroll
5  $('#gmph-scroll-down a[href^="#"]').on('click', function (e) {
6      e.preventDefault();
7      $(document).off("scroll");
8      
9      $('#gmph-scroll-down a').each(function () {
10          $(this).removeClass('active');
11      })
12      $(this).addClass('active');
13    
14      var target = this.hash,
15          menu = target;
16      $target = $(target);
17      $('html, body').stop().animate({
18          'scrollTop': $target.offset().top
19      }, 500, 'swing', function () {
20          window.location.hash = target;
21          $(document).on("scroll", onScroll);
22      });
23  });
24});
25
26$(document).ready(function () {
27  $(document).on("scroll", onScroll);
28
29  //smoothscroll
30  $('#gmph-nav-menu a[href^="#"]').on('click', function (e) {
31      e.preventDefault();
32      $(document).off("scroll");
33      
34      $('#gmph-nav-menu a').each(function () {
35          $(this).removeClass('active');
36          $(this).attr('aria-current','false');
37      })
38      $(this).addClass('active');
39      $(this).attr('aria-current','true');
40    
41      var target = this.hash,
42          menu = target;
43      $target = $(target);
44      $('html, body').stop().animate({'scrollTop': $target.offset().top}, 500, 'swing', function () {
45          window.location.hash = target;
46          $(document).on("scroll", onScroll);
47      });
48  });
49});
50
51/*
52var offset = $(':target').offset();
53var scrollto = offset.top - 60; // minus fixed header height
54$('html, body').animate({scrollTop:scrollto}, 0);
55*/
56
57function onScroll(event) {
58  var scrollPos = $(document).scrollTop();
59  $('#gmph-nav-menu a').each(function () {
60    var currLink = $(this);
61    var refElement = $(currLink.attr("href"));
62    if (scrollPos > ($('.sub-footer').position().top - $(window).height())) {
63      //$('#gmph-nav-wrapper').addClass("gmph-nav-hide");
64      console.log('1');
65    }
66    else if (($('#gmph-intro-wrapper').position().top - 2) < scrollPos) {
67      //$('#gmph-nav-wrapper').addClass("gmph-nav-hide");
68      //$('#gmph-nav-wrapper').removeClass("gmph-nav-hide");
69      console.log('2');
70    }
71    else {
72      //$('#gmph-nav-wrapper').addClass("gmph-nav-hide");
73      console.log('3');
74    }
75    if ((refElement.position().top - 53) <= scrollPos && refElement.position().top + refElement.height() > scrollPos) {
76      $('#gmph-nav-menu ul li a').removeClass("active");
77      currLink.addClass("active");
78    }
79    else if (scrollPos > ($('#gmph-header').height() - 2) && scrollPos < ($('#gmph-intro-wrapper').position().top) + $('#gmph-intro-wrapper').height()) {
80      $('#gmph-nav-menu ul li a').removeClass("active");
81      $('.empty').addClass("active");
82    }
83    else {
84      currLink.removeClass("active");
85    }
86  });
87}
88
89var $gmphbg1 = $('#gmph-timeline-wrapper');
90$gmphbg1.waypoint(function (direction) {
91    if (direction === 'down') {
92        $('#gmph-bg-container-0').removeClass('fadeIn');
93        $( "#gmph-bg-container-0" ).addClass( "fadeOut" );
94      } else if (direction === 'up') {
95        $('#gmph-bg-container-0').removeClass('fadeOut');
96        $( "#gmph-bg-container-0" ).addClass( "fadeIn" );
97      }
98}, { offset: '20%'});
99
100var $gmphbg2 = $('#gmph-1950');
101$gmphbg2.waypoint(function (direction) {
102    if (direction === 'down') {
103        $('#gmph-bg-container-1').removeClass('fadeIn');
104        $( "#gmph-bg-container-1" ).addClass( "fadeOut" );
105      } else if (direction === 'up') {
106        $('#gmph-bg-container-1').removeClass('fadeOut');
107        $( "#gmph-bg-container-1" ).addClass( "fadeIn" );
108      }
109}, { offset: '50%'});
110
111var $gmphbg3 = $('#gmph-1970');
112$gmphbg3.waypoint(function (direction) {
113    if (direction === 'down') {
114        $('#gmph-bg-container-2').removeClass('fadeIn');
115        $( "#gmph-bg-container-2" ).addClass( "fadeOut" );
116      } else if (direction === 'up') {
117        $('#gmph-bg-container-2').removeClass('fadeOut');
118        $( "#gmph-bg-container-2" ).addClass( "fadeIn" );
119      }
120}, { offset: '50%'});

121
122var $gmphbg3 = $('#gmph-1990');
123$gmphbg3.waypoint(function (direction) {
124    if (direction === 'down') {
125        $('#gmph-bg-container-3').removeClass('fadeIn');
126        $( "#gmph-bg-container-3" ).addClass( "fadeOut" );
127      } else if (direction === 'up') {
128        $('#gmph-bg-container-3').removeClass('fadeOut');
129        $( "#gmph-bg-container-3" ).addClass( "fadeIn" );
130      }
131}, { offset: '20%'});