Update the docs.

- Optimize the code style of markdown list
- Increase post contents (#104, #100)

_posts/2019-08-08-text-and-typography.md

@@ -5,9 +5,11 @@ date: 2019-08-08 11:33:00 +0800
 categories: [Blogging, Demo]
 tags: [typography]
 math: true
+image: /assets/img/sample/devices-mockup.png
 ---
 
-This Jekyll template totally compatible with Markdown syntax. Now, let's take a look for the text and typography in here.
+This Jekyll template totally compatible with Markdown syntax. Now, let's have a look at the text and typography.
+
 
 ## Titles
 
@@ -37,6 +39,22 @@ Beside the lake, beneath the trees,
 
 Fluttering and dancing in the breeze.
 
+## List
+
+### Ordered list
+
+1. first item
+2. second item
+3. third item
+
+### Unordered list
+
+- item 1
+	- sub item 1
+	- sub item 2
+
+- item 2
+
 ## Block Quote
 
 > This line to shows the Block Quote.

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

@@ -124,6 +124,16 @@ math: true
 ---
 ```
 
+## Preview Image
+
+If you want to add an image to the top of the post contents, specify the url for the image by:
+
+```yaml
+---
+image: /path/to/image-file
+---
+```
+
 
 ## Pinned Posts
 

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

@@ -30,13 +30,13 @@ $ bundle install
 
 What's more, in order to generate some extra files (*categories*, *tags* and *last modified list*), we need to use some tool scripts. If your machine is running Debian or macOS, make sure that [GNU coreutils](https://www.gnu.org/software/coreutils/) is installed. Otherwise, install by:
 
-* Debian
+- Debian
 
   ```console
   $ sudo apt-get install coreutils
   ```
 
-* macOS
+- macOS
 
   ```console
   $ brew install coreutils
@@ -59,19 +59,23 @@ $ bash tools/init.sh
 What it does is:
 
 1. Remove some files or directories from your repository:
-* `.travis.yml`
-* files under `_posts`
-* folder `docs` 
+
+    - `.travis.yml`
+    - files under `_posts`
+    - folder `docs`
+
 2. If you use the `--no-gh` option, the directory `.github` will be deleted. Otherwise, setup the GitHub Action workflow by removing extension `.hook` of `.github/workflows/pages-deploy.yml.hook`, and then remove the other files and directories in folder `.github`. 
+
 3. Automatically create a commit to save the changes.
 
 ### Configuration
 
 Generally, go to `_config.yml` and configure the variables as needed. Some of them are typical options:
-* `url`
-* `avatar`
-* `timezone`
-* `theme_mode`
+
+- `url`
+- `avatar`
+- `timezone`
+- `theme_mode`
 
 ### Run Locally