bind class

hello/index.html

@@ -28,6 +28,8 @@
             <button v-on:click="reverseMessage">Reverse Message</button>
 
             <input v-model="message"> <span>{{ lenMessage }}</span>
+
+            <p class="static" v-bind:class="{ active: isActive, 'text-danger': hasError }">class</p>
         </div>
         
         <script src="app.js"></script>