CSS定位如何制作悬浮广告_absolute和right bottom组合

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.ad-banner {
  position: absolute;
  right: 20px;
  bottom: 20px;
  width: 250px;
  height: 150px;
  background-color: #ff6b6b;
  color: white;
  border-radius: 8px;
  padding: 15px;
  box-shadow: 0 4px 12px rgba(0,0,0,0.2);
  font-family: Arial, sans-serif;
  text-align: center;
  z-index: 1000; /* 确保悬浮在其他内容之上 */
}
<p>.close-btn {
float: right;
cursor: pointer;
font-weight: bold;
}</p>

document.querySelector('.close-btn').onclick = function() {
  document.querySelector('.ad-banner').style.display = 'none';
}