# Target to be Listened to
You can specify target to listen scroll event of.
```html
<n-back-top
  :target="target"
  :bottom="220"
  :visibility-height="10"
  :style="{
    transition: 'all .3s cubic-bezier(.4, 0, .2, 1)'
  }"
  :themed-style="{
    light: {
      color: 'rgb(0, 0, 0)',
      backgroundColor: 'rgba(0, 0, 0, .3)'
    },
    dark: {
      color: 'rgb(255, 255, 255)',
      backgroundColor: 'rgba(255, 255, 255, .3)'
    }
  }"
>
   <div style="width: 200px; height: 40px; line-height: 40px; text-align: center; font-size: 14px;">
    Specify Target
  </div>
</n-back-top>
<div ref="scrollContainer" style="overflow: auto; height: 72px; line-height: 1.5;">
  A funny joke is need to be wrote here.<br/>
  A funny joke is need to be wrote here.<br/>
  A funny joke is need to be wrote here.<br/>
  A funny joke is need to be wrote here.<br/>
  A funny joke is need to be wrote here.<br/>
  A funny joke is need to be wrote here.<br/>
  A funny joke is need to be wrote here.<br/>
</div>
```
```js
export default {
  data () {
    return {
      target: () => this.$refs.scrollContainer
    }
  }
}
```