naive-ui/demo/documentation/components/configProvider/enUS/namespace.md

Namespace (Class on Detached DOM)

Some parts of component are detached to document.body. If you want to add a class to those detached elements, use namespace prop of n-config-provider. Open devtools to see detached part.

<n-config-provider :namespace="ns">
  <n-tooltip
    placement="bottom"
    trigger="click"
  >
    <template v-slot:activator>
      <n-button
        @click="isActive = true"
      >
        Activate Component with Detached Content
      </n-button>
    </template>
    <span>
      Detached Part
    </span>
  </n-tooltip>
</n-config-provider>

export default {
  data () {
    return {
      ns: 'custom-app-namespace1',
      isActive: false
    }
  }
}