Layout

.container
    display: flex
.left
    width: 100px
.center
    flex: 1
.right
    width: 100px

.container
    display: flex
    justify-content: center
    align-items: center

.container
  display: flex
.container > :nth-child(4){
  margin-left: auto // margin 会填充剩余空间
}