CSS悬浮提示框实现方法详解

<div class="tooltip">
  悬停我
  <span class="tooltiptext">这是一个提示文本</span>
</div>

.tooltip {
  position: relative;
  display: inline-block;
  cursor: pointer;
}

.tooltiptext {
  visibility: hidden;
  width: 120px;
  background-color: #333;
  color: #fff;
  text-align: center;
  border-radius: 6px;
  padding: 8px;
  position: absolute;
  z-index: 1;
  bottom: 125%; /* 显示在元素上方 */
  left: 50%;
  margin-left: -60px; /* 宽度一半，居中 */
  opacity: 0;
  transition: opacity 0.3s, visibility 0.3s;
  font-size: 14px;
}

.tooltip:hover .tooltiptext {
  visibility: visible;
  opacity: 1;
}

.tooltiptext::after {
  content: "";
  position: absolute;
  top: 100%;
  left: 50%;
  margin-left: -5px;
  border-width: 5px;
  border-style: solid;
  border-color: #333 transparent transparent transparent;
}

.tooltiptext {
  top: 125%;
  bottom: auto;
}
.tooltiptext::after {
  top: -10px;
  border-color: transparent transparent #333 transparent;
  border-width: 5px;
}