diff --git a/docs/src/WapApp.vue b/docs/src/WapApp.vue
index 1155dadf2..e9ac81bd7 100644
--- a/docs/src/WapApp.vue
+++ b/docs/src/WapApp.vue
@@ -2,9 +2,9 @@
   <div>
     <van-nav-bar
       v-show="title"
-      fixed
       class="van-doc-nav-bar"
       :title="title"
+      fixed
       left-arrow
       @click-left="onBack"
     />
@@ -40,6 +40,7 @@ body {
 
 .van-doc-nav-bar {
   .van-nav-bar__title {
+    font-size: 15px;
     text-transform: capitalize;
   }
 }
diff --git a/packages/stepper/index.vue b/packages/stepper/index.vue
index 8bf207c59..7b925c0e3 100644
--- a/packages/stepper/index.vue
+++ b/packages/stepper/index.vue
@@ -79,9 +79,11 @@ export default create({
 
   watch: {
     value(val) {
-      val = this.correctValue(+val);
-      if (val !== this.currentValue) {
-        this.currentValue = val;
+      if (val !== '') {
+        val = this.correctValue(+val);
+        if (val !== this.currentValue) {
+          this.currentValue = val;
+        }
       }
     }
   },
@@ -99,8 +101,8 @@ export default create({
     },
 
     onInput(event) {
-      const val = +event.target.value;
-      this.currentValue = this.correctValue(val);
+      const { value } = event.target;
+      this.currentValue = value ? this.correctValue(+value) : value;
       this.emitInput();
     },