fix userLayout

config/config.js

@@ -43,8 +43,8 @@ export default {
   routes: [
     {
       path: '/user',
-      components: ['../layouts/UserLayout'],
-      routes: [],
+      component: '../layouts/UserLayout',
+      routes: [{ path: '/user', component: './Welcome' }],
     },
     {
       path: '/',

src/pages/Welcome.js

 import React from 'react';
 
 export default () => (
-  <p>
+  <p style={{ textAlign: 'center' }}>
     想要添加更多页面？请参考{' '}
     <a href="https://umijs.org/guide/block.html" target="_blank" rel="noopener noreferrer">
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