JSFiddle - React, Tailwind, and code Playground

HTML

<script src="https://vuejs.org/js/vue.min.js"></script>
<div id="app">
  <div v-show="loading">loading...</div>
  <div v-show="!loading">
    Main Contents
  </div>
</div>

JavaScript

new Vue({
  el: "#app",
  data: {
    loading: true
  },
  mounted() {
    setTimeout(() => {
      this.loading = false;
    }, 1000);
  }
});