App.vue File

<template>
  <div id="app">
    <Navigation></Navigation>
 <h1>Routing</h1>
 <hr>
 <transition>
    <router-view></router-view>
 </transition>

  </div>
</template>

<script>
import nav from './components/Header.vue'
export default {
  name: 'app',

  components:{
    Navigation: nav
  }
}
</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;
}

h1, h2 {
  font-weight: normal;
}


</style>

VueJs Routing