div.acWrap {
  position: relative;
}
div.acBox {
  position: absolute;
  top: 25px;
  left: 0;
  padding: 5px;
  z-index: 999;
  background: #fff;
  border: 1px solid #000;
  display: none;
}
div.acBox div:hover {
  cursor: pointer;
  background: #fea;
}