docs: update README.md

Author: funn1est

README-zh_CN.md

@@ -11,7 +11,7 @@
 
 ## 演示
 
-👉 在线预览: https://cnode.funn1est.cn
+👉 在线预览: https://cnode.f1t.io
 
 ## 快速开始
 

README.md

@@ -11,7 +11,7 @@ A frontend project for BBS community using [cnodejs.org](https://cnodejs.org/) A
 
 ## Demo
 
-👉 Online preview: https://cnode.funn1est.cn
+👉 Online preview: https://cnode.f1t.io
 
 ## Getting Started