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                <div class="hideShowDetails">
  <h1>Some Summary</h1>
  <label for="whateveryouwant" class="hideShowDetails__toggle">
    Show me more
    The input ID name isn't terribly important, as long
    as it matches the name of the label so they will
    be linked
  <input type="checkbox" id="whateveryouwant">

  <div class="hideShowDetails__details">
    <p>Some details about the thing I mentioned</p>


                .hideShowDetails {
  // Make the label look like a link or button
  .hideShowDetails__toggle {
    text-decoration: underline;
    cursor: pointer;
    color: blue;

  // Hide the default checkbox
  .hideShowDetails__toggle + input[type='checkbox'] {
    visibility: hidden;
  // The details area is hidden by default
  .hideShowDetails__details {
    display: none;
  // When the checkbox is in the "checked" state, show
  // sibling details panel
  .hideShowDetails__toggle + input:checked + .hideShowDetails__details {
    display: block;