docs: update docs detail

components/back-top/demo/basic.md

@@ -19,7 +19,8 @@ import { BackTop } from 'antd';
 ReactDOM.render(
   <div>
     <BackTop />
-    Scroll down to see the bottom right gray button.
-  </div>
-, mountNode);
+    Scroll down to see the bottom right <strong>gray</strong> button.
+  </div>,
+  mountNode
+);
 ````

components/back-top/demo/custom.md

@@ -17,23 +17,29 @@ You can customize the style of the button, just note the size limit: no more tha
 ````jsx
 import { BackTop } from 'antd';
 
-const style = {
-  height: 40,
-  width: 40,
-  lineHeight: '40px',
-  borderRadius: 4,
-  backgroundColor: '#57c5f7',
-  color: '#fff',
-  textAlign: 'center',
-  fontSize: 20,
-};
-
 ReactDOM.render(
   <div>
-    <BackTop style={{ bottom: 100 }}>
-      <div style={style}>UP</div>
+    <BackTop>
+      <div className="ant-back-top-inner">UP</div>
     </BackTop>
-    Scroll down to see the bottom right blue button.
-  </div>
-, mountNode);
+    Scroll down to see the bottom right <strong>blue</strong> button.
+  </div>,
+  mountNode
+);
+````
+
+````css
+#components-back-top-demo-custom .ant-back-top {
+  bottom: 100px;
+}
+#components-back-top-demo-custom .ant-back-top-inner {
+  height: 40px;
+  width: 40px;
+  line-height: 40px;
+  border-radius: 4px;
+  background-color: #57c5f7;
+  color: #fff;
+  text-align: center;
+  font-size: 20px;
+}
 ````

components/button/demo/size.md

@@ -20,9 +20,12 @@ If a large or small button is desired, set the `size` property to either `large`
 ````jsx
 import { Button } from 'antd';
 
-ReactDOM.render(<div>
-  <Button type="primary" size="large">Large</Button>
-  <Button type="primary">Default</Button>
-  <Button type="primary" size="small">Small</Button>
-</div>, mountNode);
+ReactDOM.render(
+  <div>
+    <Button type="primary" size="large">Large</Button>
+    <Button type="primary">Default</Button>
+    <Button type="primary" size="small">Small</Button>
+  </div>,
+  mountNode
+);
 ````

components/form/index.en-US.md

@@ -101,8 +101,9 @@ If you use `react@<15.3.0`, then, you can't use `getFieldDecorator` in stateless
 
 ### Form.Item
 
-> * If Form.Item has multiple children, `help`, `required`, and `validateStatus` can't be generated automatically.
-> * Form controls must be child of Form.Item, otherwise, you need to set `help`, `required` and `validateStatus` by yourself.
+Note:
+* If Form.Item has multiple children that had been decorated by `getFieldDecorator`, `help` and `required` and `validateStatus` can't be generated automatically.
+* Before `2.2.0`, form controls must be child of Form.Item, otherwise, you need to set `help`, `required` and `validateStatus` by yourself.
 
 | Property      | Description                                     | Type       |  Optional | Default Value |
 |-----------|------------------------------------------|-----------|-------|--------|

components/form/index.zh-CN.md

@@ -102,8 +102,9 @@ CustomizedForm = Form.create({})(CustomizedForm);
 
 ### Form.Item
 
-> * 一个 Form.Item 建议只放一个 child，有多个 child 时，`help` `required` `validateStatus` 无法自动生成。
-> * 只有当表单域为 Form.Item 的子元素时，才会自动生成 `help` `required` `validateStatus`，其它情况请自行设置。
+注意：
+* 一个 Form.Item 建议只放一个被 getFieldDecorator 装饰过的 child，当有多个被装饰过的 child 时，`help` `required` `validateStatus` 无法自动生成。
+* `2.2.0` 之前，只有当表单域为 Form.Item 的子元素时，才会自动生成 `help` `required` `validateStatus`，嵌套情况需要自行设置。
 
 | 参数      | 说明                                     | 类型       |  可选值 | 默认值 |
 |-----------|------------------------------------------|-----------|-------|--------|

components/icon/index.en-US.md

@@ -60,8 +60,8 @@ ReactDOM.render(<IconSet className="icons" catigory="other" />, mountNode);
 
 | Property | Description      | Type   | Default |
 |----------|------------------|------- |---------|
-| type | Type of ant design icons | String | - |
-| spin | Rotate icon with animation | Boolean | false |
+| type | Type of ant design icons | string | - |
+| spin | Rotate icon with animation | boolean | false |
 
 <style>
 .markdown .icons {

components/icon/index.zh-CN.md

@@ -61,8 +61,8 @@ ReactDOM.render(<IconSet className="icons" catigory="other" />, mountNode);
 
 | 参数      | 说明             | 类型      | 默认值  |
 |----------|------------------|----------|--------|
-| type | 图标类型 | String | - |
-| spin | 是否有旋转动画 | Boolean | false |
+| type | 图标类型 | string | - |
+| spin | 是否有旋转动画 | boolean | false |
 
 <style>
 .markdown .icons {