message: docs(Overlay): add embedded content demo
diff: @@ -29,6 +29,31 @@ export default {
  },
  ```
  +### Embedded Content
  +
  +```html
  +<van-overlay :show="show" @click="show = false">
  + <div class="wrapper" @click.stop>
  + <div class="block" />
  + </div>
  +</van-overlay>
  +
  +<style>
  +.wrapper {
  + display: flex;
  + align-items: center;
  + justify-content: center;
  + height: 100%;
  +}
  +
  +.block {
  + width: 120px;
  + height: 120px;
  + background-color: #fff;
  +}
  +</style>
  +```
  +
  ## API
  ### Props
  