chore: update readme and cover image

README.md

@@ -68,9 +68,8 @@ For other platforms, please refer to the [Astro Deployment Guides](https://docs.
 
 ## Documentation
 
-Work in progress...
-
-- [Theme Configuration](https://github.com/radishzzz/astro-theme-retypeset/blob/master/src/config.ts)
+- [Theme Guide](https://retypeset.radishzz.cc/en/posts/theme-guide/)
+- [Theme Configuration File](https://github.com/radishzzz/astro-theme-retypeset/blob/master/src/config.ts)
 
 ## Credits
 

README.zh.md

@@ -68,9 +68,8 @@ Retypeset 是一款基于 [Astro](https://astro.build/) 框架的静态博客主
 
 ## 文档
 
-正在施工中...
-
-- [主题配置](https://github.com/radishzzz/astro-theme-retypeset/blob/master/src/config.ts)
+- [主题指南](https://retypeset.radishzz.cc/posts/markdown-style-guide/)
+- [主题配置文件](https://github.com/radishzzz/astro-theme-retypeset/blob/master/src/config.ts)
 
 ## 鸣谢