JSFiddle - React, Tailwind, and code Playground

HTML

<script src="//unpkg.com/vue/dist/vue.js"></script>
<script src="//unpkg.com/element-ui@1.4.4/lib/index.js"></script>
<div id="app">
<template>
  <!-- `checked` should be true or false -->
  <p>{{ checked }}</p>
  <el-checkbox :value="checked" @click.stop.prevent.native="clickCh">Option</el-checkbox>
</template>
</div>

SCSS

@import url("//unpkg.com/element-ui@1.4.4/lib/theme-default/index.css");

Babel + JSX

var Main = {
    data() {
      return {
        checked: true
      };
    },
    methods: {
    clickCh: function() {
    this.checked = !this.checked;
    //alert(this.checked );
    }
    }
  };
  
var Ctor = Vue.extend(Main)
new Ctor().$mount('#app')