使箭头在悬停时与整个锚点一起工作

<div class="anchor">
  <div class="arrow"></div>
</div>

.anchor {
  position: relative;
  width: 200px;
  height: 200px;
  background-color: #f0f0f0;
}

.arrow {
  position: absolute;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 0;
  height: 0;
  border-left: 10px solid transparent;
  border-right: 10px solid transparent;
  border-top: 10px solid #000;
  transition: all 0.3s ease;
}

.arrow:hover {
  height: 0;
}