update implementation links

docs/spec/introduce.en-US.md

@@ -27,7 +27,7 @@ Ant Design, created specially for middleware design, is committed to improving t
 [React](http://facebook.github.io/react/) is used to encapsulate a library of Ant Design components. Any other version of frameworks to implement is also welcome.
 
 - [Ant Design of React](/docs/react/introduce)(official implementation)
-- <div class="outside-link internal"><a href="https://github.com/FE-Driver/vue-beauty" target="_blank">vue-beauty</a></div>
+- <div class="outside-link"><a href="https://github.com/FE-Driver/vue-beauty" target="_blank">vue-beauty</a></div>
 - <div class="outside-link internal"><a href="http://naza.alibaba.net" target="_blank">Ant Design of Angular 2.0</a></div>
 - <div class="outside-link"><a href="https://github.com/okoala/vue-antd" target="_blank">vue-antd</a></div>
 - <div class="outside-link"><a href="https://github.com/idcos/antd-ember" target="_blank">antd-ember</a></div>

docs/spec/introduce.zh-CN.md

@@ -28,7 +28,7 @@ Ant Design 是一个致力于提升『用户』和『设计者』使用体验的
 我们采用 [React](http://facebook.github.io/react/) 封装了一套 Ant Design 的组件库，也欢迎社区其他框架的实现版本。
 
 - [Ant Design of React](/docs/react/introduce)（官方实现）
-- <div class="outside-link internal"><a href="https://github.com/FE-Driver/vue-beauty" target="_blank">vue-beauty</a></div>
+- <div class="outside-link"><a href="https://github.com/FE-Driver/vue-beauty" target="_blank">vue-beauty</a></div>
 - <div class="outside-link internal"><a href="http://naza.alibaba.net" target="_blank">Ant Design of Angular 2.0</a></div>
 - <div class="outside-link"><a href="https://github.com/okoala/vue-antd" target="_blank">vue-antd</a></div>
 - <div class="outside-link"><a href="https://github.com/idcos/antd-ember" target="_blank">antd-ember</a></div>