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Here you can Sed posuere consectetur est at lobortis. Donec ullamcorper nulla non metus auctor fringilla. Maecenas sed diam eget risus varius blandit sit amet non magna. Donec id elit non mi porta gravida at eget metus. Praesent commodo cursus magna, vel scelerisque nisl consectetur et.

              <h1>Animated <abbr title="Accessible Rich Internet Applications">ARIA</abbr> hamburger menu to meet <abbr title="Web Content Accessibility Guidelines">WCAG</abbr> 2 level AA</h1>

<p>I needed a non-linear show-hide peekaboo to meet WCAG 2 level AA.<br> This one ticks the boxes, and a reusable asset to boot.</p>

<p>JavaScript is used to toggle ARIA states and control tab position while CSS attribute selectors control animation.<p>

  <a id="hamburger" href="#navigation" class="menu">
    <svg class="menu_svg" viewbox="0 0 48 48">
      <rect x="15.5" y="16.5" width="20" height="3"/>
      <rect x="15.5" y="23.5" width="20" height="3"/>
      <rect x="15.5" y="30.5" width="20" height="3"/>

<p>A <a href="#">Fake Site Search</a> between the Menu link and the navigation block.<br>Arrgh, the things you have to deal with&hellip;</p>

<nav id="navigation" class="navigation">
  <h2 class=navigation_title>Main navigation:</h2>
  <ul class=navigation_list>
    <li><a href="#">Tesco.com</a></li>
    <li><a href="#">Groceries</a></li>
    <li><a href="#">Tesco direct</a></li>
    <li><a href="#">F&amp;F clothing</a></li>
    <li><a href="#">Clubcard</a></li>
    <li><a href="#">Tesco Bank</a></li>
    <li><a href="#">Wine by the case</a></li>
    <li><a href="#">Tesco Mobile</a></li>

<p><a href="#">Fake link after navigation block</a> to test keyboard <kbd>Tab</kbd> order.</p>

<p>Strongly influenced by the work of Heydon Pickering</p>

              /* Simple animated Peekaboo show-hide */

/* Generic styling (not required) */

.menu {
  width: 40px;
  height: 40px;
  border: 0 solid;

.menu_svg {
  pointer-events: none;

.menu[aria-expanded="true"] {
  background-color: #1A1A1A;
  fill: #fff;

/* The heavy lifting is done by  3 statements */

.navigation {
  position: relative;
  margin: 0;
  padding: 0;
  transform: translate3d(0,0,0);
  backface-visibility: hidden;

  /* opacity has to finish before height to allow JS time to find first link */
  transition: visibility 0s ease-out, opacity .3s linear, max-height .5s ease-out;
  opacity: 0;
  visibility: hidden;
  max-height: 0;
  overflow: hidden;

.navigation[aria-hidden="true"] {
  transition-delay: .6s, 0s, 0s;

.navigation[aria-hidden="false"] {
  transition-delay: 0s, 0s, 0s;
  opacity: 1;
  visibility: visible;
  max-height: 12em;

/* More generic styling */

.navigation_title {
  margin: 0;
  padding: 0;
  position: absolute;
  left: -200em;

.navigation_list {
  margin: 0;
  padding: 0 2em;

.navigation_list li {
  width: 50%;
  float: left;
              function peekaboo(w, d, linkBtnId) {

  // Peekaboo - show-hide toggle
  // Toggle a section using ARIA

  "use strict";
  var openLabel = "Open and skip to navigation bypassing site search";
  var closeLabel = "Close and hide navigation";

  var _getRegionObj = function (linkObj) {
    return d.getElementById(linkObj.hash.replace("#", "")) || !1;

  var _setAriaStates = function (linkObj, regionObj, isExpanded) {
    w.requestAnimationFrame(function () {
      linkObj.setAttribute("aria-expanded", isExpanded);
      regionObj.setAttribute("aria-hidden", !isExpanded);
      linkObj.setAttribute("aria-label", isExpanded ? closeLabel : openLabel);

  var _toggleAriaStates = function (e) {

    var linkObj = e.target;
    var expanded = linkObj.getAttribute("aria-expanded") || !1;

    if (expanded) { // string "false" is boolean true here
      var regionObj = _getRegionObj(linkObj);
      if (regionObj) {

        // convert to boolean
        expanded = expanded === "true"; 
        _setAriaStates(linkObj, regionObj, !expanded);
        if (expanded) {
        } else {

          // Small delay required for focusable object to reappear in DOM
          // (transitionend event would have CSS dependencies)
          setTimeout(function() {
            (regionObj.querySelector("a") || regionObj).focus();
          }, 100);

  var _addAriaAttributes = function (linkObj) {

    var regionObj = _getRegionObj(linkObj);
    if (regionObj) {
      linkObj.setAttribute("aria-controls", regionObj.id);
      regionObj.setAttribute("aria-controlledby", linkObj.id);
      _setAriaStates(linkObj, regionObj, false);
    return regionObj;

  var initialise = function () {

    var anchor = d.getElementById(linkBtnId);
    if (anchor && _addAriaAttributes(anchor)) {
        anchor.addEventListener("click", _toggleAriaStates, !1);

  return initialise();


peekaboo(window, document, "hamburger");
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