diff --git a/public/parent.html b/public/parent.html
index 7235361..3a67b0b 100644
--- a/public/parent.html
+++ b/public/parent.html
@@ -5,7 +5,7 @@
     <meta name="viewport" content="width=device-width, initial-scale=1.0">
     <script>
       const data = {
-        type: 'iframe',
+        type: 'spec',
         title: 'Contact Form',
         items: [{
           type: 'text',
@@ -23,6 +23,9 @@
           optValues: ['Option 1', 'Option 2', 'Option 3']
         }]
       };
+      window.addEventListener('message', (event) => {
+        console.log(event.data);
+      });
       window.onload = () => {        
         const iframe = document.getElementById('iframe');
         iframe.contentWindow.postMessage(data, window.origin);
diff --git a/src/App.vue b/src/App.vue
index 9fa349b..f28860a 100644
--- a/src/App.vue
+++ b/src/App.vue
@@ -30,12 +30,18 @@
       return {
         title: undefined,
         items: [],
+        currentTitle: undefined,
         currentIdx: undefined,
         currentItem: undefined,
         currentAnswer: undefined,
         currentAnswerValue: undefined,
         currentRefilled: false,
         timestamp: undefined,
+        uiStatus: {
+          backButtonDisabled: true,
+          nextButtonText: 'Next',
+          nextButtonStatus: 'primary',
+        },
         settings: {
           allowBack: true,
         },
@@ -44,7 +50,7 @@
     created() {
       window.addEventListener('message', (event) => {
         const data = event.data;
-        if (event.source === window.parent && data && data.type === 'iframe') {
+        if (event.source === window.parent && data && data.type === 'spec') {
           this.settings = Object.assign(this.settings, data.settings);
           this.items = structuredClone(data.items);
           this.title = data.title;
@@ -53,8 +59,7 @@
           }
           
           this.currentIdx = 0;
-          this.currentItem = this.items[this.currentIdx];
-          this.timestamp = new Date().getTime();
+          this.updateItem();
         }
       });
     },
@@ -62,20 +67,39 @@
       isReady() {
         return this.items && this.title;
       },
-      displayTitle() {
-        return `${this.currentIdx + 1}. ${this.items[this.currentIdx].title}`;
-      },
-      nextButtonText() {
-        return this.currentIdx === this.items.length - 1 ? 'Submit' : 'Next';
-      },
-      nextButtonStatus() {
-        return this.currentIdx === this.items.length - 1 ? 'submit' : '';
-      },
-      backButtonStatus() {
-        return this.currentIdx === 0 ? 'disabled' : '';
-      }
     },
     methods: {
+      updateBackButton() {
+        this.uiStatus.backButtonDisabled = !this.settings.allowBack || (this.currentIdx === 0);
+      },
+      updateNextButton() {
+        if (this.currentIdx === this.items.length - 1) {
+          this.uiStatus.nextButtonText = 'Submit';
+          this.uiStatus.nextButtonStatus = 'success';
+        } else {
+          this.uiStatus.nextButtonText = 'Next';
+          this.uiStatus.nextButtonStatus = 'primary';
+        }
+      },
+      updateTitle() {
+        this.currentTitle = this.currentItem ?
+          `${this.currentIdx + 1}. ${this.currentItem.title}` : '';
+      },
+      updateItem() {
+        this.currentItem = this.items[this.currentIdx];
+        this.currentAnswer = this.items[this.currentIdx].answer;
+        this.currentRefilled = (this.currentItem.answer !== undefined);
+        this.timestamp = new Date().getTime();
+        this.updateTitle();
+        this.updateBackButton();
+        this.updateNextButton();
+      },
+      iterOptions() {
+        return this.currentItem.optTexts.map((optText, index) => [
+          optText,
+          this.currentItem.optValues ? this.currentItem.optValues[index] : optText,
+        ]);
+      },
       clickNext() {
         const item = this.items[this.currentIdx];
         item.answer = this.currentAnswer;
@@ -86,29 +110,29 @@
           this.submit();
         } else {
           this.currentIdx++;
-          this.currentAnswer = null;
-          this.currentItem = this.items[this.currentIdx];
-          this.currentRefilled = (this.currentItem.answer !== undefined);
-          this.timestamp = new Date().getTime();
+          this.updateItem();
+        }
+      },
+      autoNext() {
+        if (this.currentIdx < this.items.length - 1) {
+          this.clickNext();
         }
       },
       clickBack() {
         if (this.currentIdx > 0) {
           this.currentIdx--;
-          this.currentAnswer = this.items[this.currentIdx].answer;
-          this.currentItem = this.items[this.currentIdx];
-          this.currentRefilled = (this.currentItem.answer !== undefined);
-          this.timestamp = new Date().getTime();
+          this.updateItem();
         }
       },
       submit() {
         const results = this.items.map((item, index) => ({
           index: index,
           title: item.title,
-          answer: item.answer,
+          answer: item.answer || '',
           refilled: item.refilled,
           responseTime: item.responseTime,
         }));
+        window.parent.postMessage({ type: 'response', results }, window.origin);
         const elem = document.createElement('a');
         elem.href = 'data:text/json;charset=utf-8,' + encodeURIComponent(JSON.stringify(results));
         elem.download = 'results.json';
@@ -119,75 +143,53 @@
 </script>
 
 <template>
-  <div class="container" v-if="isReady">
-    <span class="display-title">{{ displayTitle }}</span>
-    <template v-if="currentItem.type === 'text'">
-      <div class="item text">
-        <input type="text" v-model="currentAnswer">
-      </div>
-    </template>
-    <template v-else-if="currentItem.type === 'radio'">
-      <div class="item radio" v-for="(optText, index) in currentItem.optTexts" :key="index">
-        <input type="radio" :id="index" :value="currentItem.optValues[index]" v-model="currentAnswer">
-        <label :for="index">{{ optText }}</label>
-      </div>
-    </template>
-    
-    <button
-      v-if="settings.allowBack"
-      @click="clickBack"
-      :class="backButtonStatus">Back</button>
-    <button @click="clickNext" :class="nextButtonStatus">{{ nextButtonText }}</button>
+  <div v-if="!isReady">Loading...</div>
+  <div id="container" v-if="isReady">
+    <span id="display-title">{{ currentTitle }}</span>
+    <div id="display-content">
+      <template v-if="currentItem.type === 'text'">
+        <el-input v-model="currentAnswer" style="width: 240px" placeholder="Please input" />
+      </template>
+      <template v-else-if="currentItem.type === 'radio'">
+        <div>
+          <el-radio-group
+            v-model="currentAnswer"
+            v-for="[optText, optValue] in iterOptions()"
+            :key="optValue"
+            @change="autoNext"
+          >
+            <el-radio-button :label="optText" :value="optValue" />
+          </el-radio-group>
+        </div>
+      </template>
+    </div>
+    <div id="display-buttons">
+      <el-button-group>
+        <el-button type="primary" round :disabled="uiStatus.backButtonDisabled" @click="clickBack">
+          <el-icon class="el-icon--left"><ArrowLeft /></el-icon>Back
+        </el-button>
+        <el-button :type="uiStatus.nextButtonStatus" round @click="clickNext">
+          {{ uiStatus.nextButtonText }}<el-icon class="el-icon--right"><ArrowRight /></el-icon>
+        </el-button>
+      </el-button-group>
+    </div>
   </div>
 </template>
 
 <style scoped>
-  .container {
+  #container {
     text-align: left;
     width: 100%;
   }
-  button {
-    background-color: #008CBA;
-    border: none;
-    color: white;
-    padding: 10px 20px;
-    text-align: center;
-    text-decoration: none;
-    border-radius: 5px;
-    display: inline-block;
-    font-size: 18px;
-    margin-right: 20px;
-  }
-  button.submit {
-    background-color: #4CAF50;
-  }
-  button.disabled {
-    background-color: #cccccc;
-  }
-  input[type=text] {
-    width: 100%;
-    padding: 12px 18px;
-    margin: 8px 20px 20px 0px;
-    display: inline-block;
-    box-sizing: border-box;
-    border: 2px solid #ccc;
-    border-radius: 4px;
-    font-size: 16px;
-  }
-  input[type=radio] {
-    margin-bottom: 4px;
-    margin-right: 10px;
-    text-align: left;
-  }
-  label {
-    font-size: 16px;
-  }
-  .item {
-    margin-bottom: 20px;
-    width: 100%;
-  }
-  .display-title {
+  #display-title {
     font-size: 20px;
     font-weight: bold;
   }
+  #display-content {
+    margin-top: 1ex;
+    margin-bottom: 2ex;
+  }
+  #display-buttons {
+    text-align: center;
+  }
 </style>
\ No newline at end of file