Fixed the Docs.

README.md

@@ -6,9 +6,9 @@
 
 Language: English | [简体中文](docs/README_zh-CN.md)
 
-A minimal, portfolio, sidebar, bootstrap Jekyll theme with responsive web design and focuses on text exhibition. It will help you easily record, manage and share your knowledge and experience. 
+A minimal, portfolio, sidebar, bootstrap Jekyll theme with responsive web design and focuses on text exhibition. It will help you easily record and share your knowledge. 
 
-You will get the following features:
+**Features**
 
 * Auto Dark Mode
 * Posts' Last Modified Date
@@ -24,9 +24,7 @@ You will get the following features:
 * SEO Tag
 * Performance Optimization
 
-[**Live Demo** »](https://chirpy.cotes.info)
+[![devices-mockup](https://raw.githubusercontent.com/cotes2020/jekyll-theme-chirpy/master/assets/img/sample/devices-mockup.png)](https://chirpy.cotes.info)
-
-![devices-mockup](https://raw.githubusercontent.com/cotes2020/jekyll-theme-chirpy/master/assets/img/sample/devices-mockup.png)
 
 ## Table of Contents
 
@@ -124,7 +122,7 @@ Basically, go to `_config.yml` and customize the variables as needed, some of th
 
 * `url`
 	
-	Set to your website domain and there should be no slash symbol at the tail.
+	Set to your website url and there should be no slash symbol at the tail. Format: `<protocol>://<domain>`.
 
 
 * `avatar`
@@ -242,7 +240,7 @@ For more details and the better reading experience, please check out the [tutori
 
 ## Contributing
 
-The old saying: "Tow heads are better than one. Five heads are better than two." So, welcome to report bugs, improve code quality or submit a new feature. For more information, see [contributing guidelines](.github/CONTRIBUTING.md).
+The old saying: "Two heads are better than one. Five heads are better than two." So, welcome to report bugs, improve code quality or submit a new feature. For more information, see [contributing guidelines](.github/CONTRIBUTING.md).
 
 
 ## Credits
@@ -254,7 +252,7 @@ This theme is mainly built with [Jekyll](https://jekyllrb.com/) ecosystem, [Boot
 
 ## Support
 
-If you enjoy this theme or find it helpful, please consider becoming my sponsor, I'd really appreciate it! Click the button <kbd>:heart:Sponsor</kbd> at the top of the [Home Page](https://github.com/cotes2020/jekyll-theme-chirpy) and choose a link that suits you to donate. This will encourage me and help me maintain this project.
+If you enjoy this theme or find it helpful, please consider becoming my sponsor, I'd really appreciate it! Click the button <kbd>:heart:Sponsor</kbd> at the top of the [Home Page](https://github.com/cotes2020/jekyll-theme-chirpy) and choose a link that suits you to donate; this will encourage and help me better maintain the project.
 
 
 ## License

_config.yml

@@ -17,7 +17,7 @@ description: >-                        # used by seo meta and the atom feed
   bootstrap Jekyll theme with responsive web design
   and focuses on text presentation.
 
-# Replace with your domain, e.g. 'https://username.github.io'
+# Replace with the website url, e.g. 'https://username.github.io'
 url: 'protocol://domain'
 
 author: your_full_name                  # change to your full name

_posts/2019-08-08-write-a-new-post.md

@@ -46,8 +46,8 @@ jekyll-theme-chirpy
 ├── categories
 │   ├── animal.html
 │   └── tutorial.html
-├── tags
+└── tags
-│   └── bee.html
+    └── bee.html
 ```
     
     and the content of a *category* type page is
@@ -64,11 +64,24 @@ category: CATEGORY_NAME     # e.g. Insect
 ---
 layout: tag
 title: TAG_NAME             # e.g. bee
-category: TAG_NAME          # e.g. bee
+tag: TAG_NAME               # e.g. bee
 ---
 ```
 
-    With the increasing number of posts, the number of categories and tags will increase several times!  If we still manually create these *category*/*tag* type files, it will obviously be a super time-consuming job, and it is very likely to miss some of them(i.e. when you click on the missing `category` or `tag` link from a post or somewhere, it will complain to you '404'). The good news is that we got a lovely script tool to finish the pages creation stuff: `tools/init.sh`. See its usage [here]({{ "/posts/getting-started/#option-1-built-by-github-pages" | relative_url }}).
+    With the increasing number of posts, the number of categories and tags will increase several times!  If we still manually create these *category*/*tag* type files, it will obviously be a super time-consuming job, and it is very likely to miss some of them(i.e. when you click on the missing `category` or `tag` link from a post or somewhere, it will complain to you '404'). The good news is that we got a lovely script tool `_scripts/py/pages_generator.py` to finish the boring task. Basically we will use it via `tools/init.sh` instead of running it separately. Check out its use case [here]({{ "/posts/getting-started/#option-1-built-by-github-pages" | relative_url }}).
+
+- **Last modified date**
+    
+    The last modified date of the posts is recorded as `seo.date_modified`, for example:
+```yaml
+---
+seo:
+    date_modified: 2020-01-04 17:05:41 +0800
+---
+```
+
+    This date is equal to the lastest git-commit date of the post file and can be automatically generated by the tool script `_scripts/py/update_posts_lastmod.py`. Similar to the other script `pages_generator.py` mentioned above, it is also be called from `tools/init.sh`, so it doesn't have to be used separately.
+    
 
 ## Table of Contents
 

_posts/2019-08-09-getting-started.md

@@ -77,7 +77,7 @@ Basically, go to `_config.yml` and customize the variables as needed, some of th
 
 * `url`
     
-    Set to your website domain and there should be no slash symbol at the tail.
+    Set to your website url and there should be no slash symbol at the tail. Format: `<protocol>://<domain>`.
 
 
 * `avatar`

docs/README_zh-CN.md

@@ -4,7 +4,7 @@
 [![GitHub license](https://img.shields.io/github/license/cotes2020/jekyll-theme-chirpy.svg)](https://github.com/cotes2020/jekyll-theme-chirpy/blob/master/LICENSE)
 [![996.icu](https://img.shields.io/badge/link-996.icu-%23FF4D5B.svg)](https://996.icu)
 
-Language: [English](../README.md) | 简体中文
+选择语言: [English](../README.md) | 简体中文
 
 一个不一样的 Jekyll 主题（内附神秘工具），采用响应式设计，方便记录、管理、分享你的知识和经验。
 
@@ -24,9 +24,8 @@ Language: [English](../README.md) | 简体中文
 * SEO 优化
 * 网站性能优化
 
-[**在线体验** »](https://chirpy.cotes.info)
 
-![devices-mockup](https://raw.githubusercontent.com/cotes2020/jekyll-theme-chirpy/master/assets/img/sample/devices-mockup.png)
+[![devices-mockup](https://raw.githubusercontent.com/cotes2020/jekyll-theme-chirpy/master/assets/img/sample/devices-mockup.png)](https://chirpy.cotes.info)
 
 ## 目录