feat: 增加 flex 布局的支持

components/layout/demo/flex-align.md

@@ -0,0 +1,40 @@
+# Flex Align
+
+- order: 5 
+
+Flex 子元素垂直对齐
+
+
+---
+
+
+````html
+<div class="row-flex center top">
+  <div class="col-4 hight-100">2</div>
+  <div class="col-4 hight-50">2</div>
+  <div class="col-4 hight-120">2</div>
+  <div class="col-4 hight-80">2</div>
+</div>
+<p>顶部对齐</p>
+
+<div class="row-flex space-around middle">
+  <div class="col-4 hight-100">2</div>
+  <div class="col-4 hight-50">2</div>
+  <div class="col-4 hight-120">2</div>
+  <div class="col-4 hight-80">2</div>
+</div>
+<p>居中对齐</p>
+
+<div class="row-flex space-between bottom">
+  <div class="col-4 hight-100">2</div>
+  <div class="col-4 hight-50">2</div>
+  <div class="col-4 hight-120">2</div>
+  <div class="col-4 hight-80">2</div>
+</div>
+<p>底部对齐</p>
+
+````
+
+
+
+

components/layout/demo/flex-order.md

@@ -0,0 +1,23 @@
+# Flex Order
+
+- order: 6 
+
+通过 Flex 布局的 Order 来改变元素的排序
+
+
+---
+
+
+````html
+<div class="row-flex">
+  <div class="col-6 col-order-4">1 col-order-4</div>
+  <div class="col-6 col-order-3">2 col-order-3</div>
+  <div class="col-6 col-order-2">3 col-order-2</div>
+  <div class="col-6 col-order-1">4 col-order-1</div>
+</div>
+
+````
+
+
+
+

components/layout/demo/flex.md

@@ -0,0 +1,57 @@
+# Flex Basic
+
+- order: 4 
+
+Flex 布局基础
+
+使用 `row-flex` 定义 `flex` 布局，其子元素根据不同的值 `start`,`center`,`end`,`space-between`,`space-around`，分别定义其在父节点里面的排版方式。
+
+---
+
+````html
+
+<div class="row-flex start">
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+</div>
+<p>子元素居左排列</p>
+
+<div class="row-flex center">
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+</div>
+<p>子元素居中排列</p>
+
+<div class="row-flex end">
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+</div>
+<p>子元素居右排列</p>
+
+<div class="row-flex space-between">
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+</div>
+<p>子元素等宽排列</p>
+
+<div class="row-flex space-around">
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+  <div class="col-4">2</div>
+</div>
+<p>子元素分散对齐</p>
+
+````
+
+
+
+

components/layout/index.md

@@ -68,13 +68,19 @@
 * 栅格系统中的列是指1到24的值来表示其跨越的范围。例如，三个等宽d的列可以使用`.col-8`来创建
 * 如果一个`row`中的`col`总和超过24，那么多余的`col`会作为一个整体另起一行排列
 
+## Flex 布局
+
+我们的栅格化系统支持 Flex 布局，允许子元素在父节点内的水平对齐方式 - 居左、居中、居右、等宽排列、分散排列。子元素与子元素之间，支持顶部对齐、垂直居中对齐、底部对齐的方式。同时，支持使用 order 来定义元素的排列顺序。
+
 
 <style>
-.row {
+.row,
+.row-flex {
     background-image: linear-gradient(90deg, #F5F5F5 4.16666667%, transparent 4.16666667%, transparent 8.33333333%, #F5F5F5 8.33333333%, #F5F5F5 12.5%,  transparent 12.5%, transparent 16.66666667%, #F5F5F5 16.66666667%, #F5F5F5 20.83333333%, transparent 20.83333333%, transparent 25%, #F5F5F5 25%, #F5F5F5 29.16666667%, transparent 29.16666667%, transparent 33.33333333%, #F5F5F5 33.33333333%, #F5F5F5 37.5%, transparent 37.5%, transparent 41.66666667%, #F5F5F5 41.66666667%, #F5F5F5 45.83333333%, transparent 45.83333333%, transparent 50%, #F5F5F5 50%, #F5F5F5 54.16666667%, transparent 54.16666667%, transparent 58.33333333%, #F5F5F5 58.33333333%, #F5F5F5 62.5%, transparent 62.5%, transparent 66.66666667%, #F5F5F5 66.66666667%, #F5F5F5 70.83333333%,  transparent 70.83333333%, transparent 75%, #F5F5F5 75%, #F5F5F5 79.16666667%, transparent 79.16666667%, transparent 83.33333333%, #F5F5F5 83.33333333%, #F5F5F5 87.5%, transparent 87.5%, transparent 91.66666667%, #F5F5F5 91.66666667%, #F5F5F5 95.83333333%, transparent 95.83333333%);
 }
 
-.row div {
+.row div,
+.row-flex div {
   padding: 5px 0;
   background: rgba(24, 115, 216, 0.7);
   text-align: center;
@@ -112,4 +118,16 @@
   color: #999;
 }
 
+.hight-100 {
+	height: 100px;
+}
+.hight-50 {
+	height: 50px;
+}
+.hight-120 {
+	height: 120px;
+}
+.hight-80 {
+	height: 80px;
+}
 </style>

style/core/layouts.less

@@ -37,5 +37,79 @@
   }
 }
 
+// x轴原点
+.row-flex.start,
+.row-flex.start.top,
+.row-flex.start.middle,
+.row-flex.start.bottom {
+  justify-content: flex-start;
+}
+
+// x轴居中
+.row-flex.center,
+.row-flex.center.top,
+.row-flex.center.middle,
+.row-flex.center.bottom {
+  justify-content: center;
+}
+
+// x轴反方向
+.row-flex.end,
+.row-flex.end.top,
+.row-flex.end.middle,
+.row-flex.end.bottom {
+  justify-content: flex-end;
+}
+
+// x轴平分
+.row-flex.space-between,
+.row-flex.space-between.top,
+.row-flex.space-between.middle,
+.row-flex.space-between.bottom {
+  justify-content: space-between;
+}
+
+// x轴有间隔地平分
+.row-flex.space-around,
+.row-flex.space-around.top,
+.row-flex.space-around.middle,
+.row-flex.space-around.bottom {
+  justify-content: space-around;
+}
+
+// 顶部对齐
+.row-flex.center.top,
+.row-flex.start.top,
+.row-flex.end.top,
+.row-flex.space-between.top,
+.row-flex.space-around.top {
+  align-items: flex-start;
+}
+
+// 居中对齐
+.row-flex.center.middle,
+.row-flex.start.middle,
+.row-flex.end.middle,
+.row-flex.space-between.middle,
+.row-flex.space-around.middle {
+ align-items: center;
+}
+
+// 底部对齐
+.row-flex.center.bottom,
+.row-flex.start.bottom,
+.row-flex.end.bottom,
+.row-flex.space-between.bottom,
+.row-flex.space-around.bottom {
+ align-items: flex-end;
+}
+
+.col {
+  position: relative;
+  display: block;
+  float: left;
+  flex: 0 0 auto;
+}
+
 .make-grid-columns();
 .make-grid();