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                <h2>A11Y - Modals</h2>

<button class="modal__show">Show Modal</button>

<p>Lorem Ipsum is simply dummy text of the printing and typesetting industry. Lorem Ipsum has been the industry's standard dummy text ever since the 1500s, when an unknown printer took a galley of type and scrambled it to make a type specimen book. </p>

  <li><a href="#">Primary</a></li>
  <li><a href="#">Secondary</a></li>

<div class="modal" id="modal" tabindex="-1" role="dialog" aria-labelled-by="modaltitle">
  <div class="modal__content">
    <h2 id="modaltitle" tabindex="-1">Modal window</h2>
    <p>It is a long established fact that a reader will be distracted by the readable content of a page when looking at its layout.</p>
    <form action="#">
        <label for="firstname">First name</label>
        <input type="text" id="firstname" />
        <label for="lastname">Last name</label>
        <input type="text" id="lastname" />

    <button class="modal__close">


                .modal {
  background-color: rgba(0,0,0,0.5);
  height: 100vh;
  width: 100vw;
  position: absolute;
  left: 0;
  top: 0;
  display: none;

.modal--visible {
  display: flex;
  justify-content: center;
  align-items: center;

.modal__content {
  background-color: rgb(255, 255, 255);
    height: 70%;
  width: 70%;
  padding: 2rem;
  position: relative;

.modal__close {
  background-color: #000000;
    position: absolute;
  right: -1rem;
  top: -1rem;
    color: #ffffff;

:focus {
  outline: 4px solid #FF0000;


                // Button to trigger the modal window
var button = document.querySelector('.modal__show');
// Variable for storing the last focused element
var lastFocusedElement;
// Close button in modal window
var closeButton = document.querySelector('.modal__close')

// Open modal window on click
button.addEventListener('click', showModal);

// Show Mmdal
function showModal() {
  // Close all open modal windows
  // Store the last focused element
  lastFocusedElement = document.activeElement;
  // Select the modal window
  var modal = document.getElementById('modal');
  // Show the window
  // Find all focusable children
  var focusableElementsString = 'a[href], area[href], input:not([disabled]), select:not([disabled]), textarea:not([disabled]), button:not([disabled]), iframe, object, embed, [tabindex="0"], [tabindex="-1"], [contenteditable]';
  var focusableElements = modal.querySelectorAll(focusableElementsString);
  // Convert NodeList to Array
  focusableElements =;

  // The first focusable element within the modal window
  var firstTabStop = focusableElements[0];
  // The last focusable element within the modal window
  var lastTabStop = focusableElements[focusableElements.length - 1];
  // Focus the window
  // Add keydown event
  modal.addEventListener('keydown', function(e) {
    // Listen for the Tab key
    if (e.keyCode === 9) {
      // If Shift + Tab
      if (e.shiftKey) {
        // If the current element in focus is the first focusable element within the modal window...
        if (document.activeElement === firstTabStop) {
          // ...jump to the last focusable element
      // if Tab
      } else {
        // If the current element in focus is the last focusable element within the modal window...
        if (document.activeElement === lastTabStop) {
          // ...jump to the first focusable element
    // Close the window by pressing the Esc-key
    if(e.keyCode === 27) {

// Close the window by clicking the close button
document.querySelector('.modal__close').addEventListener('click', removeModal);

// Remove the modal window if it's visible
function removeModal() {
  var visibleClass = 'modal--visible';
  if (document.querySelector('.' + visibleClass)) {
    document.querySelector('.' + visibleClass).classList.remove(visibleClass);
    // Return the focus to the last focused element