https://basecamp.com/assets/js/modules/menu.js?v=1.6.0

1function ready() {
2
3  const menuToggle = document.querySelector('.menu-toggle');
4  const menu = document.getElementById('menu');
5
6  if(!menuToggle || !menu) return;
7
8  function inert(value) {
9
10    document.querySelectorAll('main.main, footer.footer, .signup').forEach((el) => el.inert = value);
11
12  }
13
14  function open() {
15
16    document.documentElement.classList.add('menu-open');
17    menuToggle.setAttribute('aria-expanded', 'true');
18    menuToggle.setAttribute('aria-label', 'Close navigation');
19
20    inert(true);
21
22  }
23
24  function close() {
25
26    const wasOpen = document.documentElement.classList.contains('menu-open');
27    const hadFocus = menu.contains(document.activeElement);
28
29    document.documentElement.classList.remove('menu-open');
30    menuToggle.setAttribute('aria-expanded', 'false');
31    menuToggle.setAttribute('aria-label', 'Open navigation');
32
33    inert(false);
34
35    if(wasOpen && hadFocus) menuToggle.focus();
36
37  }
38
39  menuToggle.addEventListener('click', () => {
40
41    document.documentElement.classList.contains('menu-open') ? close() : open();
42
43  });
44
45  menu.addEventListener('click', (e) => {
46
47    if(e.target !== menu) return;
48
49    close();
50
51    menuToggle.focus();
52
53  });
54
55  document.addEventListener('focusin', (e) => {
56
57    if(menu.contains(e.target) || menuToggle.contains(e.target)) return;
58
59    close();
60
61  });
62
63  addEventListener('pageshow', close);
64
65  matchMedia('(min-width: 64em)').addEventListener('change', (e) => {
66
67    if(e.matches) close();
68
69  });
70
71  document.addEventListener('keydown', (e) => {
72
73    if(e.key === 'Escape') close();
74
75  });
76
77}
78
79export { ready };