justify-content
- justify-content:center
-
- justify-content:flex-start
-
-
justify-content:flex-end
-
- justify-content:space-around
-
-
justify-content:space-between
-
aligin-items
- aligin-items:flex-start
- align-items:flex-end
- align-items:center
- align-items:stretch(不设置高度时等高显示)