盒子

导航

尺寸
撑大盒子： 主体 + padding + border
内减模式：box-sizing: border-box

margin
版心居中：margin: 0 auto;

border
点 dotted
虚 dashed
实 solid

padding
上右下左
上中下
顺时针

垂直

水平

内外 class="father"
1 display: flex;

2 display: flex; justify-content: center;

3 display: flex; justify-content: end;

4 display: flex; align-items: center;

5 display: flex;justify-content: center; align-items: center;

6 display: flex;justify-content: end; align-items: center;

7 display: flex; align-items: end;

8 display: flex; justify-content: center; align-items: end;

9 display: flex; justify-content: end; align-items: end;