箭头

.errBox{
  font-size: 12px;
  position: absolute;
  top:40px;
  color: #ff0000;
  border:1px solid #ff0000;
  width:120px;
  line-height:22px;
  text-align:center;
  background-color: #ffffff;
  z-index: 1;
}
.errBox::after{
  width: 8px;
  height: 8px;
  border-top: 1px solid #ff0000;
  border-right: 1px solid #ff0000;
  transform: rotate(-45deg);
  content: '';position: absolute;top: -5px;left:55px;z-index: 1;
  background-color: #ffffff;
}