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                <p data-toggletip>
  This clarifies whatever needs clarifying.


                .toggletip-container {
  position: relative;
  display: inline-block;

/* the bubble element, added inside the toggletip live region */

.toggletip-bubble {
  display: inline-block;
  position: absolute;
  left: 100%;
  top: 0;
  width: 10em;
  padding: 0.5rem;
  background: #000;
  color: #fff;

/* boilerplate; nothing really to see here */

html {
  font-size: 150%;
  font-family: sans-serif;

* {
  font-size: inherit;

button {
  width: 2em;
  height: 2em;
  border-radius: 50%;
  border: 0;
  background: #000;
  font-family: serif;
  font-weight: bold;
  color: #fff;


                (function() {
  // Get all the toggletip buttons
  var toggletipTexts = document.querySelectorAll('[data-toggletip]');

  // Iterate over them, function(toggletipText) {
    // Create the container element
    var container = document.createElement('span');
    container.setAttribute('class', 'toggletip-container');
    // Put it before the original element in the DOM
    toggletipText.parentNode.insertBefore(container, toggletipText);
    // Create the button element
    var toggletip = document.createElement('button');
    toggletip.setAttribute('type', 'button');
    toggletip.setAttribute('aria-label', 'more info');
    toggletip.setAttribute('data-toggletip-content', toggletipText.textContent);
    toggletip.textContent = 'i';
    // Place the button element in the container
    // Create the live region
    var liveRegion = document.createElement('span');
    liveRegion.setAttribute('role', 'status');
    // Place the live region in the container
    // Remove the original element
    // Build `data-tooltip-content` 
    var message = toggletip.getAttribute('data-toggletip-content');
    toggletip.setAttribute('data-toggletip-content', message);
    // Get the message from the data-content element
    var message = toggletip.getAttribute('data-toggletip-content');

    // Get the live region element
    var liveRegion = toggletip.nextElementSibling;

    // Toggle the message
    toggletip.addEventListener('click', function() {
        liveRegion.innerHTML = '';
        window.setTimeout(function() {
          liveRegion.innerHTML = '<span class="toggletip-bubble">'+ message +'</span>';
        }, 100);

    // Close on outside click
    document.addEventListener('click', function (e) {
      if (toggletip !== {
        liveRegion.innerHTML = '';

    // Remove toggletip on ESC
    toggletip.addEventListener('keydown', function(e) {
      if ((e.keyCode || e.which) === 27)
      liveRegion.innerHTML = '';
    // Remove on blur
    toggletip.addEventListener('blur', function (e) {
      liveRegion.innerHTML = '';