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  Checkbox input used as a toggle thanks to the :checked pseudo-class.
  The `id` attribute is necessary to make it possible to check it through the label.
<input type="checkbox" class="toggle" id="toggle" />

  Label from which the `for` attribute should match the one from the checkbox toggle.
<label for="toggle">Toggle content</label>

  Content meant to be collapsed/expanded depending on the state of the checkbox.
<div class="toggled">
  <p>Pellentesque habitant morbi tristique senectus et netus et malesuada fames ac turpis egestas. Vestibulum tortor quam, feugiat vitae, ultricies eget, tempor sit amet, ante. Donec eu libero sit amet quam egestas semper. Aenean ultricies mi vitae est. Mauris placerat eleifend leo.</p>  



 * Elegant and accessible content toggle with CSS.
 * 1. Hides the toggle, as it can be toggled through the label thanks to the id/for combo.
 * 2. Hides the toggled content when not following a checked toggled.
 * Courtesy to H5BP for the visually hidden ruleset:
.toggle, /* 1 */
.toggle:not(:checked) ~ .toggled /* 2 */ {
  border: 0;
  clip: rect(0 0 0 0);
  height: 1px;
  margin: -1px;
  overflow: hidden;
  padding: 0;
  position: absolute;
  width: 1px;

.toggle:focus ~ label {
  color: deeppink;

 Demo styles, not interesting.

body {
  max-width: 600px;
  margin: 2em auto;
  background: #FDFDFD;
  padding: 1em;

label {
  border: 1px solid;
  padding: 5px;
  cursor: pointer;