MDN的flex说明::https://developer.mozilla.org/en-US/docs/Web/CSS/flex
重要属性:flex,flex-direction,align-content,align-items,justify-content order
flex item不设置高度,默认等于flex容器高度
不设置flex-direction,默认就是flex-direction: row;有横向,纵向,反横向,反纵向。row|row-reverse |column|column-reverse;
flex item 3
flex里面item的几个属性:auto就是1:1自适应;initial就是最小适应,none就是不适应,N数字就是按比例
flex: auto
flex: initial;width:100px;这个最宽是100px,能自适应低于100px
flex: none;不会大小适应
flex用N数字就是按比例,下列就是2:5:3
flex: 2;
flex: 5;
flex: 3;
flex反横向
1-flex: 3;
2-flex: 6;
3-flex: 9;flex里面嵌套flex当然可以呀
flex-wrap: wrap
2
3
4
A Complete Guide to Flexbox https://css-tricks.com/snippets/css/a-guide-to-flexbox/