diff --git a/app.js b/app.js
index e41bcbe..7b0f6ef 100644
--- a/app.js
+++ b/app.js
@@ -1,15 +1,6 @@
 var app = new Vue({
   el: '#app',
   data: {
-    color: "gray",
-    width: 100
-  },
-  computed:{
-    myStyle(){
-      return {
-        backgroundColor: this.color,
-        width: this.width + "px"
-      }
-    }
+    show: true
   }
 });
diff --git a/index.html b/index.html
index adefdbd..52c6981 100644
--- a/index.html
+++ b/index.html
@@ -7,12 +7,11 @@
   </head>
   <body>
     <div id='app'>
-      <div class="demo" :style="{backgroundColor: color}"></div>
-      <div class="demo" :style="myStyle"></div>
-      <div class="demo" :style="[myStyle, {height: width + 'px'}]"></div>
-      <hr>
-      <input type="text"  v-model="color">
-      <input type="text"  v-model="width">
+      <button type="button" name="button" @click="show = !show">Switch</button>
+
+      <p v-if="show">You can see me</p>
+      <p v-else>Now you see me</p>
+      <p>Do you also see me?</p>
     </div>
     <script src="app.js" charset="utf-8"></script>
   </body>
