Get your own Vue server
App.vue
InfoBox.vue
GrandChild.vue
main.js
 
<template>
  <h2>Example $root Object</h2>
  <p v-bind:style="{ backgroundColor: color }">The 'color' data property can be reached and manipulated directly from a child component, even far down the component tree structure, by the use of the $root object.</p>
  <info-box />
</template>

<script>
export default {
  data() {
    return {
      color: 'pink'
    }
  }
}
</script>                  
<template>
  <div>
    <h3>Child Component</h3>
    <grand-child />
  </div>
</template>

<style scoped>
div {
  border: solid black 1px;
  padding: 10px;
  width: 250px;
}
</style>                  
<template>
  <div>
    <h4>Grand Child Component</h4>
    <p>Click the button to toggle the color of the P tag in the root component.</p>
    <button v-on:click="this.$root.color='lightgreen'">Change color in root</button>
  </div>
</template>

<style scoped>
div {
  border: solid black 1px;
  padding: 10px;
  width: 100%;
  box-sizing: border-box;
}
</style>                  
import { createApp } from 'vue'

import App from './App.vue'
import InfoBox from './components/InfoBox.vue'
import GrandChild from './components/GrandChild.vue'

const app = createApp(App)
app.component('info-box', InfoBox)
app.component('grand-child', GrandChild)
app.mount('#app')
                  
http://localhost:5173/