Vue

by Max Sinev

HTML

<div id="app">
  <div v-bind:class="{ alert: showAlert }" style="width: 50px; height: 50px;"></div>
  <button @click="showAlert = !showAlert">Toggle</button>
</div>

CSS

.alert {
  background-color: red;
  width: 100%;
  height:
}

Vue

new Vue({
  el: "#app",
  data: {
    showAlert: true
  }
})