title: how to add styling when app is mounted? vue js
body: <p>i have a template code like this</p>
    
  <p>this is my script code</p>
  <pre><code>   data () {
      return {
        loadPage: true
      }
    },
    mounted () {
      this.loadPage = true
    },
  </code></pre>
  <p>this is my styling code</p>
  <pre><code>#app{
    width: 100%;
    opacity: 0;
    transition: opacity 0.5s ease-in-out;
  }
  </code></pre>
  <p>I want to set a class/Id styling after it is mounted (setting their opacity to 1) Is there any simple way to accomplish this? Examples would be appreciated</p>