diff --git a/app.js b/app.js
index dc81d94..e41bcbe 100644
--- a/app.js
+++ b/app.js
@@ -1,16 +1,14 @@
 var app = new Vue({
   el: '#app',
   data: {
-    attachRed: false,
-    attachGreen: false,
-    attachBlue: true,
-    color: "green"
+    color: "gray",
+    width: 100
   },
   computed:{
-    divClasses(){
+    myStyle(){
       return {
-        red: this.attachRed,
-        blue: !this.attachRed
+        backgroundColor: this.color,
+        width: this.width + "px"
       }
     }
   }
diff --git a/index.html b/index.html
index 7baf188..f3d613b 100644
--- a/index.html
+++ b/index.html
@@ -7,14 +7,12 @@
   </head>
   <body>
     <div id='app'>
-      <div class="demo"
-          @click="attachRed = !attachRed"
-          :class="{red: attachRed}"
-          ></div>
-          <div class="demo" :class="divClasses"></div>
-          <div class="demo" :class="[color, {red: attachRed}]"></div>
-          <hr>
-          <input type="text"  v-model="color">
+      <div class="demo" :style="myStyle"></div>
+      <div class="demo"></div>
+      <div class="demo"></div>
+      <hr>
+      <input type="text"  v-model="color">
+      <input type="text"  v-model="width">
     </div>
     <script src="app.js" charset="utf-8"></script>
   </body>
