元素无法垂直居中？

Question

元素无法垂直居中

Answer 1

.side-tool a i {

  line-height:40px;

  /*vertical-align: middle;*/

}

Answer 2

.side-tool{

  display: flex;

  flex-direction: column;

  justify-content: center;

  align-items: center;

  position:  fixed;

  right: 1%;

  bottom: 5%;

  width: 40px;

  border: 1px solid #eee;

  background-color: white;

  text-align: center;

  font-size: 24px;

  z-index: 1040;

}