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<div class="container">
  <div class="contents">
    <div class="post">
      <div class="item" style="pointer-events: auto"></div>
    </div>
  </div>
</div>
body {background-color: ghostwhite}
div::before {content: attr(class); font-size: 13px}
div {margin: 10px 50px; border: 3px solid tomato; background-color: #fff; pointer-events: none}
.item {border-color: skyblue}
div:active { border-color: purple }
body:active { background-color: lightgray }