使 <h2> 元素不可见 - 在线编辑器

          <!DOCTYPE html>
<html>
<head>
  <style>
    h1.visible {
      visibility: visible
    }

    h1.hidden {
      visibility: hidden
    }
  </style>
</head>

<body>
  <h1 class="visible">This is a visible heading</h1>
  <h1 class="hidden">This is an invisible heading</h1>
  <p>Notice that the invisible heading still takes up space.</p>
</body>

</html>
        