diff --git a/docs/assets/design.sketch b/docs/assets/design.sketch
index 00a02eba7..de2f91579 100755
Binary files a/docs/assets/design.sketch and b/docs/assets/design.sketch differ
diff --git a/packages/vant-cli/site/common/style/base.less b/packages/vant-cli/site/common/style/base.less
index 7bb9384f5..86c418300 100644
--- a/packages/vant-cli/site/common/style/base.less
+++ b/packages/vant-cli/site/common/style/base.less
@@ -7,7 +7,7 @@ body {
   color: @van-doc-black;
   font-size: 16px;
   font-family: -apple-system, BlinkMacSystemFont, 'Helvetica Neue', Helvetica,
-    Segoe UI, Arial, Roboto, 'PingFang SC', 'Hiragino Sans GB',
+    Segoe UI, Arial, Roboto, 'PingFang SC', 'miui', 'Hiragino Sans GB',
     'Microsoft Yahei', sans-serif;
   background-color: @van-doc-background-color;
   -webkit-font-smoothing: antialiased;
diff --git a/src/number-keyboard/index.js b/src/number-keyboard/index.js
index d6ed998fe..1d6ab5735 100644
--- a/src/number-keyboard/index.js
+++ b/src/number-keyboard/index.js
@@ -113,13 +113,13 @@ export default createComponent({
       if (extraKeys.length === 1) {
         keys.push(
           { text: 0, wider: true },
-          { text: extraKey[0], type: 'extra' }
+          { text: extraKeys[0], type: 'extra' }
         );
       } else if (extraKeys.length === 2) {
         keys.push(
-          { text: extraKey[0], type: 'extra' },
+          { text: extraKeys[0], type: 'extra' },
           { text: 0 },
-          { text: extraKey[1], type: 'extra' }
+          { text: extraKeys[1], type: 'extra' }
         );
       }
 
diff --git a/src/number-keyboard/test/__snapshots__/index.spec.js.snap b/src/number-keyboard/test/__snapshots__/index.spec.js.snap
index 928a45c13..ad366e2b4 100644
--- a/src/number-keyboard/test/__snapshots__/index.spec.js.snap
+++ b/src/number-keyboard/test/__snapshots__/index.spec.js.snap
@@ -1,5 +1,52 @@
 // Jest Snapshot v1, https://goo.gl/fbAQLP
 
+exports[`extra-key prop 1`] = `
+<div class="van-number-keyboard" style="display: none;" name="van-slide-up">
+  <div class="van-number-keyboard__body">
+    <div class="van-number-keyboard__keys">
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">1</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">2</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">3</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">4</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">5</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">6</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">7</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">8</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">9</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">foo</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key">0</div>
+      </div>
+      <div class="van-key__wrapper">
+        <div role="button" tabindex="0" class="van-key van-key--delete"><svg viewBox="0 0 32 22" xmlns="http://www.w3.org/2000/svg" class="van-key__delete-icon">
+            <path d="M28.016 0A3.991 3.991 0 0132 3.987v14.026c0 2.2-1.787 3.987-3.98 3.987H10.382c-.509 0-.996-.206-1.374-.585L.89 13.09C.33 12.62 0 11.84 0 11.006c0-.86.325-1.62.887-2.08L9.01.585A1.936 1.936 0 0110.383 0zm0 1.947H10.368L2.24 10.28c-.224.226-.312.432-.312.73 0 .287.094.51.312.729l8.128 8.333h17.648a2.041 2.041 0 002.037-2.04V3.987c0-1.127-.915-2.04-2.037-2.04zM23.028 6a.96.96 0 01.678.292.95.95 0 01-.003 1.377l-3.342 3.348 3.326 3.333c.189.188.292.43.292.679 0 .248-.103.49-.292.679a.96.96 0 01-.678.292.959.959 0 01-.677-.292L18.99 12.36l-3.343 3.345a.96.96 0 01-.677.292.96.96 0 01-.678-.292.962.962 0 01-.292-.68c0-.248.104-.49.292-.679l3.342-3.348-3.342-3.348A.963.963 0 0114 6.971c0-.248.104-.49.292-.679A.96.96 0 0114.97 6a.96.96 0 01.677.292l3.358 3.348 3.345-3.348A.96.96 0 0123.028 6z" fill="currentColor"></path>
+          </svg></div>
+      </div>
+    </div>
+  </div>
+</div>
+`;
+
 exports[`extra-key slot 1`] = `
 <div class="van-number-keyboard" style="display: none;" name="van-slide-up">
   <div class="van-number-keyboard__body">
diff --git a/src/number-keyboard/test/index.spec.js b/src/number-keyboard/test/index.spec.js
index 0a8ccc48b..39990660e 100644
--- a/src/number-keyboard/test/index.spec.js
+++ b/src/number-keyboard/test/index.spec.js
@@ -93,6 +93,16 @@ test('title-left slot', () => {
   expect(wrapper).toMatchSnapshot();
 });
 
+test('extra-key prop', () => {
+  const wrapper = mount(NumberKeyboard, {
+    propsData: {
+      extraKey: 'foo',
+    },
+  });
+
+  expect(wrapper).toMatchSnapshot();
+});
+
 test('extra-key slot', () => {
   const wrapper = mount(NumberKeyboard, {
     scopedSlots: {
diff --git a/src/style/var.less b/src/style/var.less
index 25eac5107..482362e7e 100644
--- a/src/style/var.less
+++ b/src/style/var.less
@@ -48,7 +48,7 @@
 @line-height-md: 20px;
 @line-height-lg: 22px;
 @base-font-family: -apple-system, BlinkMacSystemFont, 'Helvetica Neue',
-  Helvetica, Segoe UI, Arial, Roboto, 'PingFang SC', 'Hiragino Sans GB',
+  Helvetica, Segoe UI, Arial, Roboto, 'PingFang SC', 'miui', 'Hiragino Sans GB',
   'Microsoft Yahei', sans-serif;
 @price-integer-font-family: Avenir-Heavy, PingFang SC, Helvetica Neue, Arial,
   sans-serif;