Backstage/src/App.vue

<template>
  <div class="layout" id="ctrl">
    <router-view class="view" />
  </div>
</template>

<script>
import '@/assets/style/index.css'

export default {
  name: 'app'
}
</script>

<style>
  html, body {
    height: 100%;
  }
  .layout {
    height: 100%;
  }
</style>