docs: uniform color

src/calendar/README.md

@@ -111,7 +111,7 @@ Set `show-confirm` to `false` to hide the confirm button. In this case, the `con
 Use `color` prop to custom calendar color.
 
 ```html
-<van-calendar v-model="show" color="#07c160" />
+<van-calendar v-model="show" color="#1989fa" />
 ```
 
 ### Custom Date Range

src/calendar/README.zh-CN.md

@@ -113,7 +113,7 @@ export default {
 通过 `color` 属性可以自定义日历的颜色，对选中日期和底部按钮生效。
 
 ```html
-<van-calendar v-model="show" color="#07c160" />
+<van-calendar v-model="show" color="#1989fa" />
 ```
 
 ### 自定义日期范围

src/calendar/demo/index.vue

@@ -121,7 +121,7 @@
 </template>
 
 <script>
-import { GREEN } from '../../utils/constant';
+import { BLUE } from '../../utils/constant';
 
 export default {
   i18n: {
@@ -235,7 +235,7 @@ export default {
           this.showConfirm = false;
           break;
         case 'customColor':
-          this.color = GREEN;
+          this.color = BLUE;
           break;
         case 'customConfirm':
           this.confirmText = this.t('confirmText');