Simple APP.vue starter from VUE UI CLI

App.vue

<!-- FILE: App.vue -->
<!-- NOTE: Install  and Import bootstrap on main.js  -->

<template>
  <div id="app">
    <bootsAlert/>
  </div>
</template>

<script>
import bootsAlert from './components/bootsAlert.vue'

export default {
  name: 'App',
  components: {
    bootsAlert
  }
}
</script>

<style>
#app {
  font-family: Avenir, Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-align: center;
  color: #2c3e50;
  margin-top: 60px;
}
</style>

bootsAlert.vue

<!-- FILE: components/bootsAlert.vue -->

<template>
  <div>
    <div class="alert alert-danger" role="alert" style="margin:auto;width:600px;">
      Such Alert Very Danger !
    </div>
  </div>
</template>

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