https://liwoli.at/themes/custom/amro_tw_26/js/readability-toggle.js?v=11.3.7

1/**
2 * @file
3 * Readable / Unreadable font toggle for AMRO 26.
4 *
5 * Readable:   Headlines in League Mono Bold
6 * Unreadable: Headlines in AMRO26 Fingerprint Mono
7 */
8(function (Drupal, once) {
9  'use strict';
10
11  var STORAGE_KEY = 'amro26_readability';
12
13  function applyMode(mode) {
14    if (mode === 'unreadable') {
15      document.body.classList.add('amro-unreadable');
16      document.body.classList.remove('amro-readable');
17    } else {
18      document.body.classList.add('amro-readable');
19      document.body.classList.remove('amro-unreadable');
20    }
21  }
22
23  function getStoredMode() {
24    try {
25      return localStorage.getItem(STORAGE_KEY) || 'unreadable';
26    } catch (e) {
27      return 'readable';
28    }
29  }
30
31  function storeMode(mode) {
32    try {
33      localStorage.setItem(STORAGE_KEY, mode);
34    } catch (e) {
35      // Storage not available.
36    }
37  }
38
39  // Apply stored mode immediately to avoid flash of wrong font.
40  applyMode(getStoredMode());
41
42  Drupal.behaviors.amroReadabilityToggle = {
43    attach: function (context) {
44      once('readability-toggle', '[data-readability-toggle]', context).forEach(function (btn) {
45        var currentMode = getStoredMode();
46        applyMode(currentMode);
47        updateButton(btn, currentMode);
48
49        btn.addEventListener('click', function () {
50          var mode = document.body.classList.contains('amro-unreadable') ? 'readable' : 'unreadable';
51          applyMode(mode);
52          storeMode(mode);
53          updateButton(btn, mode);
54        });
55      });
56    }
57  };
58
59  function updateButton(btn, mode) {
60    var readableLabel = btn.querySelector('.amro-readability-label--readable');
61    var unreadableLabel = btn.querySelector('.amro-readability-label--unreadable');
62    var knob = btn.querySelector('.amro-readability-knob');
63
64    if (mode === 'unreadable') {
65      btn.classList.add('is-unreadable');
66      btn.setAttribute('aria-pressed', 'true');
67    } else {
68      btn.classList.remove('is-unreadable');
69      btn.setAttribute('aria-pressed', 'false');
70    }
71  }
72
73})(Drupal, once);