<div class="sticky-header">
  <h1>粘性标题</h1>
</div>

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  top: 0;
  width: 100%;
  background-color: #f1f1f1;
  padding: 10px;
  text-align: center;
  z-index: 9999;
}

window.addEventListener('scroll', function() {
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});

.sticky-header.sticky {
  position: fixed;
  top: 0;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}