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<h1><a href="">Accessible tab navigation to meet <abbr title="Web Content Accessibility Guidelines">WCAG</abbr> 2 using <abbr title="Accessible Rich Internet Applications">ARIA</abbr> roles</a></h1>
  <div class="new_version">
    <h2>New for 2023 version 7</h2>
    <a href="" target=_self>Accessible tab navigation (WCAG 2.1)</a>
    <p>A complete rewrite, progressively enhanced, fully keyboard accessible, positionable tabs, improved ARIA semantics, and responsive.</p>

<p>Use the <kbd>Tab</kbd> key to jump link to visible link, and the arrow keys to navigate across the tabs.</p>
<p>A <strong>white focus outline</strong> is applied as an aid to visualisation but it is <strong>not</strong> a requirement.</p>

<div class=tl_container>

  <!-- A plain set of anchor links in HTML -->

  <ul class="tl_list">
    <li><a href="#A" class=a>Section A</a></li>
    <li><a href="#B" class="b ON">Section B</a></li>
    <li><a href="#C" class=c>Section C</a></li>

  <section id=A class="tl_section a">
    <h2>Content heading A</h2>
    <p>Copy with an <a href="#">Example focusable link</a> as content for A1.</p>

  <section id=B class="tl_section b">
    <h2>Content heading B</h2>
    <p>Copy with an <a href="#">Example focusable link</a> as content for B1.</p>

  <section id=C class="tl_section c">
    <h2>Content heading C</h2>
    <p>Copy without a focusable link as content for C1.</p>

    <!-- A second embedded tablist example -->
    <ul class="tl_list">
      <li><a href=#D class=d>Sub-section D</a></li>
      <li><a href=#E class="tl_lnk-on e">Sub-section E</a></li>

    <div id=D class="tl_section d">
      <h2>Content heading D</h2>
      <p>Copy without a focusable link as content for D.</p>

    <div id=E class="tl_section e">
      <h2>Content heading E</h2>
      <p>Copy without a focusable link as content for E.</p>


  <p>Updated (19-03-2017) to include up / down arrow keys and nested tablists.</p>

  <p>Available as a Github repo: <a href="" target=_blank title="[new window]">Accessible tabs</a>.</p>

 <p>There's an option to allow mouse hover to activate a tab by adding the class "hoverable" to the  tablist <code>ul</code>. Not so sure it's a good idea though.</p>

<!-- <p>As used on the <a href="" target=_blank title="[new window]">Tesco Easter 2016 hub</a> (Opening hours results). <a href="" target=_blank title="[new window]">Permanent copy</a></p> -->

<p id=addToggle></p>


<p>Personally, I'd avoid this type of interface. It has poor usability and is confusing to operate.</p>

<p>The method provided here is a furtherence of Heydon Pickering's <a href="">Tab interface</a>.</p>

<p>Please read and consider Thierry Koblentz's article: <a href="">Tab Panel, the right way&hellip;</a> which doesn't use anchors as tab activators. Pankaj Parashar has a supporting CodePen <a href="">Awesome Accessible Tabpanel</a>.</p>

<p>Jeff Smith's article: <a href="">Danger! ARIA tabs</a> has good arguments, though I'm not completely sold on the suggested solution: <a href="">Standard tabs without ARIA roles </a>.</p>




                .new_version {
  color: #ccc;
  background-color: hsla(240, 50%, 25%, 0.25);
  border: 2px solid red;
  margin: 2rem 0;
  padding: 1rem;
  position: relative;
.new_version > * {
  margin: 0;
.new_version > a {
  display: inline-block;
  font-size: 1.25rem;
  font-weight: 300;
  margin: 1rem 0;
.new_version > a::before {
  content: "";
  position: absolute;
  inset: 0;
.new_version > p {
  display: block;
  font-weight: 300;

/* Tab styling (optional) */

.tl_container {margin: 2rem 0;}

.tl_list {
  display: flex;
  padding: 0;
  margin: 0;
  align-items: center;
  justify-content: left;
  list-style: none;

.tl_list li {
  margin: 0;
  width: 33.3333%;
  text-align: center;
  border-radius: 4px 4px 0 0;

.tl_list a {
  color: #fff;
  padding: 1rem 0.5rem;
  display: block;
  border: none;
  text-decoration: none;
  text-shadow: none;
.tl_list a:hover,
.tl_list a:focus {
  text-shadow: 0 2px 4px #000

/* White focus ring - so you can see when it's focussed (not required) */
.tl_section h2:focus {
  outline: 1px solid currentcolor;

/* Section styling (optional) */

.tl_section {
  padding: 1rem 1.5rem;
  min-height: 8rem;
  border-radius: 0 0 4px 4px;
  text-shadow: none;
.tl_section h2 {
  margin-top: 1rem;

/* tab & panel colour */

.a:focus {background-color: rgba(255,85,160,.3);}
.b:focus  {background-color: rgba(160,255,85,.3);}
.c:focus  {background-color: rgba(85,160,255,.3);}
.d:focus  {background-color: rgba(85,160,255,.25);}
.e:focus  {background-color: rgba(85,160,255,.5);}

Section styling (required)
Removes hidden sections from the keychain. 
Only used when JavaScript is available.
[role="tabpanel"][aria-hidden="true"] {
  display: none;



Simple Accessible Tab control v6.1.1 19-03-2017
Author: Mike Foskett
Incept: 09-03-2016
Furtherence of: Heydon Pickering -

  Uses ARIA attributes (via CSS) to control what's visible.

  Requires (tested):
    addEventListener (IE8+)
    preventDefault (IE9+)
    classList (IE10+)
    querySelectorAll (IE9+)

  Required parameter:

  Optional parameters:

    tabListClass : "tl_list" (default)

    onClass : "ON" (default)
            Customisable, set default tab on.
            Used for initialisation only.

    hoverableClass : "tl-hoverable" (default)
            Customisable, allow mouse-hover to switch tabs.
            Apply to the navigation ul.

  Version 6.1.1 - 19-03-2017 - Added: up/down arrow keys; nested tablists
  Version 6.1 - 16-08-2016
  Version 6 - 10-07-2016
  Version 5.2 - 17-03-2016
  Version 5 - 09-03-2016
  Version 4 - 27-01-2012
  Version 3 - 25-01-2012
  Version 1 - 27-05-2010

var accessibleTabs6 = (function () {

  "use strict";

  var d = document;
  var tabListClass;
  var onClass;
  var hoverableClass;

  var setTabsOff = function (tabList) {
    var i = tabList.tabs.length;
    while (i--) {
      setTab(tabList.tabs[i], false);

  var setTab = function (tab, switchOn) {
    if (tab && tab.panelId) {
      d.getElementById(tab.panelId).setAttribute("aria-hidden", !switchOn);
      tab.setAttribute("aria-selected", switchOn);
      tab.setAttribute("tabindex", switchOn ? "0" : "-1");

  var _activateTab = function (e) {
    var tab =;
    if (e.preventDefault) {
      setTab(tab, true);

  var _keypressed = function (e) {

    var tab =;
    var newNo = -1;
    var tabs = tab.tabList.tabs;
    var maxNo = tabs.length - 1;

    if (e.keyCode === 37 || e.keyCode === 38) { // left / up arrow
      newNo = ( === 0) ? maxNo : - 1;
    if (e.keyCode === 39 || e.keyCode === 40) { // right arrow / down arrow
      newNo = ( === maxNo) ? 0 : + 1;

    if (newNo > -1) {
      setTab(tabs[newNo], true);

  var _tabHovered = function (e) {
    var a =;
    var useHover = a.tabList.classList.contains(hoverableClass);
    if (useHover) {

  var _events = function (tab) {
    tab.addEventListener("click", _activateTab, false);
    tab.addEventListener("keydown", _keypressed, false);
    tab.addEventListener("mouseover", _tabHovered, false);

  var _initialiseAriaAttributes = function (tab) {

    var tabPanel = d.getElementById(tab.panelId);

    tab.parentNode.setAttribute("role", "presentation");
    tab.setAttribute("role", "tab");
    tab.setAttribute("aria-controls", tab.panelId);

    tabPanel.setAttribute("role", "tabpanel");

    // Make first <section> object keyboard focussable
    // Preferably a heading
    // Tabindex=0 to work both forwards and backwards through the keychain
    tabPanel.children[0].setAttribute("tabindex", "0");


  var _setUpConfig = function (cfg) {
    tabListClass = cfg.tabListClass || "tl_list";
    onClass = cfg.onClass || "ON";
    hoverableClass = cfg.hoverableClass || "tl-hoverable";

  var _setUpTab = function (tab, panelId, count) { = count; = "tab-" + panelId;
    tab.panelId = panelId;

  var _initialiseTabList = function (tabList) {

    var defaultTab = 0;
    var panelId;
    var tabPanel;
    var i;

    if (tabList) {

      tabList.setAttribute("role", "tablist");
      tabList.tabs = tabList.getElementsByTagName("a");
      i = tabList.tabs.length;

      while (i--) {

        tabList.tabs[i].tabList = tabList;

        panelId = tabList.tabs[i].href.slice(tabList.tabs[i].href.lastIndexOf("#") + 1);
        tabPanel = d.getElementById(panelId);

        if (tabPanel) {
          _setUpTab(tabList.tabs[i], panelId, i);
          if (tabList.tabs[i].classList.contains(onClass)) {
            defaultTab = i;

            // onClass only used to declare intial state, so remove from DOM
      if (tabList.tabs[defaultTab] && tabList.tabs[defaultTab].panelId) {
        setTab(tabList.tabs[defaultTab], true);

  var _isMustardCut = function (e) {
    // check browser feature support (IE10+)
    return (
      (typeof d.querySelectorAll === "function") &&
      d.addEventListener &&
      !!d.documentElement.classList // IE10+

  var init = function (cfg) {
    var tabLists;
    var i;

    if (_isMustardCut()) {
      tabLists = d.getElementsByClassName(tabListClass);
      i = tabLists.length;
      while (i--) {

  return {
    init: init


  tabListClass : "tl_list",   // default, may omit
  onClass : "ON",               // default, may omit
  hoverableClass : "tl-hoverable"  // default, may omit