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                <span class="toggletip-container">
  <button type="button" aria-label="more info" data-toggletip-content="This clarifies whatever needs clarifying">i</button>
  <span role="status"></span>


                .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;

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

button:focus {
  outline: none;
  box-shadow: 0 0 0 0.25rem skyBlue;

/* boilerplate; nothing really to see here */

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

* {
  font-size: inherit;


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

  // Iterate over them, function (toggletip) {
    // 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 = '';