<div id="app">
  <button class="btn btn-secondary" v-on:click="counter++">Button clicked {{ counter }} times</button>
</div>

html, body {
  display: grid;
  justify-content: center;
  align-content: center;
  width: 100%;
  height: 100%;
  
}

const app = Vue.createApp({
  data: function () {
    return { counter: 0 }
  }
})

const vm = app.mount('#app')