Update docs of front-matter

source/docs/advanced-settings/front-matter.md

@@ -29,18 +29,19 @@ Next extends and provide more variables. It allows users to configure a single p
 
 Setting | Type | Description | Default
 --- | --- | --- | ---
-`author` | `string` | Author name for post copyright | `author` in Hexo `_config.yml`
-`post_link` | `string` | Post link | None
+`author` | `string` | Author name for post copyright | `author` in Hexo config file
+`post_link` | `string` | The original link of the reposted article | None
+`link` | `string` | Clicking on the post title on the index or archive page will redirect to the set external link | None
 `description` | `string` | Docs [here](/docs/theme-settings/posts.html#Preamble-Text) | None
 `direction` | `string` | Available value: `rtl` | None
 `header` | `boolean` | Whether to display the post header in index page | `true`
-`mathjax` | `boolean` | MathJax support | `math.every_page` in `_config.yml`
-`sidebar` | `boolean` | Whether the sidebar will be shown | Depends on `sidebar.display` in `_config.yml`
-`copyright` | `boolean` | Whether to display copyright notices below the post with `theme.creative_commons.license` and `theme.creative_commons.post` enabled | `true`
+`mathjax` | `boolean` | MathJax support | Depends on `math.every_page` in NexT config file
+`sidebar` | `boolean` | Whether the sidebar will be shown | Depends on `sidebar.display` in NexT config file
+`copyright` | `boolean` | Whether to display copyright notices below the post with `creative_commons.license` and `creative_commons.post` enabled | `true`
 `sticky` | `number` | Pin the post to the top of the index page. [hexo-generator-index](https://github.com/hexojs/hexo-generator-index) plugin required | 0
-`quicklink` | `object` (1) | Quicklink support | From `_config.yml`
-`reward_settings` | `object` (1) | Reward settings | From `_config.yml`
-`toc` | `object` (1) | Table of Contents in the sidebar | From `_config.yml`
+`quicklink` | `object` (1) | Quicklink support | From NexT config file
+`reward_settings` | `object` (1) | Reward settings | From NexT config file
+`toc` | `object` (1) | Table of Contents in the sidebar | From NexT config file
 
 (1): They have the same structure as the options in {% label primary@NexT config file %}.