版权文字修复

src/components/PageContent/index.js

@@ -22,7 +22,7 @@ export default (props) => {
           margin: '20px 0',
         }}
       >
-        Copyright   2021-2031 by GreenTech. All Rights Reserved.
+        Copyright © 2021-2031 by GreenTech. All Rights Reserved.
       </div>
     </div>
   );