### 基本用法

``` html
<u-panel title="任务总览">
    <u-skeleton></u-skeleton>
</u-panel>
```

``` html
<u-panel title="服务">
    <u-panel-group title="当天概览">
        <u-skeleton></u-skeleton>
    </u-panel-group>
    <u-panel-group title="事务分组">
        <u-skeleton></u-skeleton>
    </u-panel-group>
</u-panel>
```
