Vue 过度动画

<template>
  <div id="app">
    <img src="./assets/logo.png">
    <br>
    <router-link to="/">Home</router-link>|
    <router-link to="/params/198/jspang website is verygood">params</router-link>| 
    <router-link to="/goHome">goHome</router-link>|   
    <router-link to="/goParams/918/i live vuejs">goparams</router-link>|    
    <router-link to="/hi1">Hi1</router-link>
    <router-link to="/jspang">jspang</router-link>

    <transition name="fade" mode="out-in">
      <router-view/>
    </transition>
    
    
  </div>
</template>

<script>
export default {
  name: 'App'
}
</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;
}
.fade-enter {
  opacity:0;
}
.fade-leave{
  opacity:1;
}
.fade-enter-active{
  transition:opacity .5s;
}
.fade-leave-active{
  opacity:0;
  transition:opacity .5s;
}
</style>

<transition name="fade" mode="out-in">
      <router-view/>
    </transition>