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  <h1 class="header">Screen Reader Friendly CSS Tabs to Accordion</h1>
  <p>These are CSS radio button tabs. They will turn into an accordion at lower screen width via media queries. Tabs can be focused on with the tab key. Keyboard navigation between tabs is done through arrow keys. Up and left arrows to move back a tab, down/right arrows will move forward. Tab again to focus off of the tabs. Multiple instances per page is doable as well. <br/><br/><a href="">Focus Test</a></p>
<div class="tab-container">
  <input name="tabset1" type="radio" id="tabset1-1" checked="checked" />
  <label for="tabset1-1">Tabset1 - Tab 1 Label</label>
  <div class="panel">
    <h1>Tabset1 - Tab 1 header</h1>
    <p>Tabset1 - Tab 1 paragraph</p>

  <input name="tabset1" type="radio" id="tabset1-2" />
  <label for="tabset1-2">Tabset1 - Tab 2 Label</label>
  <div class="panel">
    <h1>Tabset1 - Tab 2 header</h1>
    <p>Tabset1 - Tab 2 paragraph</p>

  <input name="tabset1" type="radio" id="tabset1-3" />
  <label for="tabset1-3">Tabset1 - Tab 3 Label</label>
  <div class="panel">
    <h1>Tabset1 - Tab 3 header</h1>
    <p>Tabset1 - Tab 3 paragraph</p>

<p>And a second set of vertical tabs - note how the names and ids in the HTML are different.</p>
<div id="vertical" class="tab-container">
  <input name="vertical" type="radio" id="vertical-1" checked="checked" />
  <label for="vertical-1">Vertical 1 Label</label>
  <div class="panel">
    <h1>Vertical - Tab 1 header</h1>
    <p>Vertical - Tab 1 paragraph</p>

  <input name="vertical" type="radio" id="vertical-2" />
  <label for="vertical-2">Vertical 2 Label</label>
  <div class="panel">
    <h1>Vertical Tab 2 header</h1>
    <p>Vertical Tab 2 paragraph</p>

  <input name="vertical" type="radio" id="vertical-3" />
  <label for="vertical-3">Vertical 3 Label</label>
  <div class="panel">
    <h1>Vertical Tab 3 header</h1>
    <p>Vertical Tab 3 paragraph</p>


                /* Some basic styling */
:root {
    --bg-color: #111;
    --txt-color: #eee;
    --link-color: #374c5d;
    --link2-color: #fff;
    --darktxt-color: #a0a0a0;
    --accent1-color: #232323;
    --accent2-color: #252D34;

*, html {font-size: 16px; line-height: 150%; box-sizing: border-box;}
body {background: var(--bg-color); color: var(--txt-color); font-family: arial, sans-serif; font-size: 1rem;}

a:link, a:visited, a:active {
  color: var(--link-color);
a:hover {
  color: var(--link2-color);

h1, h2, h3, h4, h5, h6 {
    display: block;
    font-size: inherit;
    font-weight: inherit;
    padding: 0;
    margin: 5px 0;
p {
    font-size: 1rem;
    margin: 5px 0;
    padding: 0;
    text-indent: 30px;

.header {
    background: var(--accent1-color);
    border-bottom: 10px solid var(--accent2-color);
    color: var(--darktxt-color);
    font-family: georgia, serif;
    font-size: 1.5rem;
    font-weight: bold;
    letter-spacing: 2px;
    padding: 8px 2px;
    text-align: center;

main {
    border:2px solid var(--link-color);
    padding: 15px;

/* This wraps around the tabs, keeping them all in one area */
.tab-container {
  display: flex;
	flex-wrap: wrap;
  width: 50%;
  margin: 10px auto;
  padding: 5px;
  border: 2px solid var(--accent1-color);

/* Hide the checkbox, do not use display:none as it prevents keyboard users navigating through the tabs */
.tab-container input[type="radio"] {
  width: 0;
  height: 0;
  margin: 0;
  opacity: 0;
  padding: 0;
  border: none;
  -moz-appearance: none;
  -webkit-appearance: none;
  appearance: none;

/* The label of the input, this is what you see and click on instead of an ugly radio button */
.tab-container label {
  order: 1;
  cursor: pointer;
  border-bottom: 2px solid var(--link2-color);
  color: var(--link2-color);
  padding: 5px 15px;
  transition: all ease-out 0.2s 0.1s;

/* The label "tab" when clicked */
.tab-container input[type="radio"]:checked + label {
	border-bottom: 2px solid var(--link-color);
  color: var(--link-color);
  cursor: default;

/* How the label appears to keyboard users when it is focused on  */
.tab-container input[type="radio"]:focus + label {
  outline: 1px solid var(--link2-color);

/* Panel styles */
.panel {
  order: 99;
  flex-grow: 0;
  flex-basis: 0;
  width: 0;
  height: 0;
  position: fixed;
  top: 0;
  left: 0;
  z-index: -1;
  opacity: 0;
  visibility: hidden;

/* Show panel when corresponding label is clicked
* This is where your tab panel styles like height, padding, backgrounds and fonts go */
.tab-container input[type="radio"]:checked + label + .panel {
  position: relative;
  visibility: visible;
  z-index: 1;
  opacity: 1;
  transition: opacity ease-out 0.2s 0.1s;
  flex-basis: 100%;
  height: 150px;
  padding: 10px;
  border: 2px solid var(--accent2-color);
  overflow: auto;

/* Vertical ID tabs will be vertical instead */ {flex-direction: column; height: 375px;} label {width: 20%; flex-basis: unset; flex-grow: 0;} input[type="radio"]:checked + label + .panel {width: 80%; height:100%; top: 0; overflow: auto;}

@media (max-width: 1000px) {
  .tab-container {
    width: 100%;
  .tab-container .panel,
  .tab-container label {
    order: initial;
  .tab-container label {
    width: 100%!important;
    margin-right: 0;
    margin-top: 0.2rem;
  .tab-container input[type="radio"]:checked + label + .panel {
    height: unset;
  } {width: 100%; height: unset; flex-direction: row;} label {width: 100%;flex-basis: 100%;} input[type="radio"]:checked + label + .panel {width: 100%;}