史上最全面的 Markdown 语法总览终极参考！

GitHub Flavored Markdown (GFM) 语法总览。
虽然 Markdown 的核心语法元素是有限的，但通过组合、嵌套和特定于 GitHub 的扩展功能，可以实现非常丰富的效果。

一、基本文本格式 (1-15)

标题 H1 (Setext-style): This is an H1 + =======

This is an H1
标题 H2 (Setext-style): This is an H2 + -------

This is an H2
标题 H1 (ATX-style): # H1

H1
标题 H2 (ATX-style): ## H2

H2
标题 H3 (ATX-style): ### H3

H3
标题 H4 (ATX-style): #### H4

H4
标题 H5 (ATX-style): ##### H5

H5
标题 H6 (ATX-style): ###### H6

H6
粗体 (Asterisks): **bold text**

bold text
粗体 (Underscores): __bold text__

bold text
斜体 (Asterisk): *italicized text*

italicized text
斜体 (Underscore): _italicized text_

italicized text
粗斜体 (Asterisks): ***bold and italic***

bold and italic
粗斜体 (Underscores): ___bold and italic___

bold and italic
删除线 (GFM): ~~The world is flat.~~

~~The world is flat.~~

二、列表 (16-30)

无序列表 - 星号: * Item
- Item 1
- Item 2
无序列表 - 加号: + Item
- Item 1
- Item 2
无序列表 - 连字符: - Item
- Item 1
- Item 2
有序列表: 1. First item
1. First item
2. Second item
嵌套列表 (无序内有序): * Item + 1. Nested ordered
- Item
  1. Nested ordered
  2. Another nested
嵌套列表 (有序内无序): 1. First + * Nested unordered
1. First
  - Nested unordered
  - Another nested
任务列表 (GFM): - [x] Completed task
- Completed task
- Incomplete task
列表项内的段落: * First line + + Paragraph break
- This is the first line.
  
  And this is a paragraph within the list item.
列表项内的代码块: * Code: + + ` ```code````
- Here is some code:
```
function hello() { console.log("hi"); }
```
列表项内的引用: * Quote: + + > quote
- A quote here:
  
  This is a quote inside a list.
不同层级缩进的列表 (Level 2): * Level 1 + + Level 2
- Level 1
  - Level 2
    - Level 3
不同标记混用的列表 (Level 2): 1. Ordered + * Unordered nested
1. Ordered
  - Unordered nested
2. Next ordered
紧凑列表 (无空行): * Item 1 + * Item 2
- Item 1
- Item 2
列表项内多个段落 (再次强调): * Para 1 + + Para 2
- This is the first paragraph in the list item.
  
  This is the second paragraph in the same list item.
列表中的复杂结构 (综合): 在列表项中混合使用代码、引用等。
- Complex Item:
  1. Step one.
    console.log('code');
  2. Step two.
    
    A nested quote.

三、链接与图片 (31-45)

内联链接: [title](https://example.com)

My Website
带标题的内联链接: [title](https://example.com "Optional title")

My Website
自动链接 (URL): <https://www.example.com>

https://www.example.com
参考式链接 (定义): [Reference link][id] + [id]: https://example.com

Reference link
图片 (内联): ![alt text](/path/to/img.jpg)
带链接的图片: [![alt text](/path/to/img.jpg)](https://example.com)
图片 (参考式): ![alt text][img-id] + [img-id]: /path/to/img.jpg
为图片添加链接 (方法二): 使用HTML <a> 标签。

<a href="https://example.com"><img src="https://placehold.co/150" alt="An image" /></a>
调整图片大小 (HTML): <img src="..." width="200" height="100">

<img src="https://placehold.co/150" width="100" />
居中图片 (HTML/CSS): <p align="center">...<img>...</p>

<p align="center"><img src="https://placehold.co/150" /></p>
链接到锚点: [Go to Section](#section-title)

(需要页面内有对应的 ## Section Title )
链接到仓库文件: [Link to file](./path/to/file.md)

Link to README
链接到 Issues/Pull Requests: #123

See issue #123 for more details.
链接到特定用户: @username

Thanks for your contribution, @octocat!
链接到特定提交 (Commit): 00213a8bd...

The fix was introduced in 00213a8bd...

四、引用与水平线 (46-55)

基本引用: > blockquote

This is a blockquote.
嵌套引用: > Outer + >> Inner

This is the outer quote.

This is the inner quote.
引用内含列表: > * List in quote
- A list item in a blockquote
- Another item
引用内含代码: > code``

Inline code inside a blockquote.
引用内含标题: > # Title in quote

A heading in a blockquote
引用后紧跟段落: 正确的格式需要用两个空格换行或空行分隔。

This is a quote.

This is a new paragraph.
多段落引用 (Paragraph breaks): > Para 1 + > + > Para 2

This is the first paragraph of the blockquote.

This is the second paragraph.
水平线 (连字符): ---
水平线 (星号): ***
水平线 (下划线): ___

五、代码 (56-70)

行内代码: `code`

Here is some inline code.
代码块 (围栏式, 无语言):
```
...
code here
...
```
```
Sample text here...
```

代码块 (围栏式, 指定语言):

...python
def hello():
    print("Hello")
...

def hello():
    print("Hello")

代码块 (缩进式): Indent every line with 4 spaces.
```
function hello() {
    console.log("Hello");
}
```
包含反引号的行内代码: ```` `code` ``

This is `backticks` inside inline code.
代码块中的缩进: 保持代码原有的缩进。
```
{
  "key": "value"
}
```
代码块中的特殊字符: 代码块会原样显示，无需转义。
```
<div class="test"> &lt; &gt; </div>
```
行内高亮 (非标准): GitHub 不直接支持，但可用HTML <mark>。

Use <mark>highlighted</mark> text.

长代码块 (滚动): 长代码会自动出现横向滚动条。

This is a very long line of text that will demonstrate the horizontal scrolling behavior of a code block in GitHub Flavored Markdown. It should allow users to scroll horizontally to see all the content without breaking the layout.

代码块内换行: 在代码语言标识符后加 {1,2} 可指定高亮行（此为YAML Front Matter风格，非GFM标准，但某些渲染器支持）。

(此功能非GFM标准，不保证通用性)
注释 (HTML): 
转义字符 (Backslash): \*literal asterisks\*

*literal asterisks*
转义反引号: ```literal backtick``

\literal backtick`(显示为 ` ``)
转义井号: \# Not a header

# Not a header
转义感叹号: \! Not an image

! Not an image

六、表格 (GFM 扩展, 71-80)

基本表格:

| Syntax      | Description |
| ----------- | ----------- |
| Header      | Title       |
| Paragraph   | Text        |

Syntax Description

Header Title

Paragraph Text

左对齐 (默认): | :--- |

Left-aligned

Content
右对齐: | ---: |

Right-aligned

Content
居中对齐: | :---: |

Center-aligned

Content
混合对齐:

Left Center Right

A B C
表格内使用行内格式: | *Italic* | **Bold** |

Italic Bold Code

Cell 1 Cell 2 Cell 3
空单元格表格:

Col 1 Col 2

Data

Data
长文本换行:

Short Long Text Column

A This is a very long piece of text that will wrap within the table cell to demonstrate how content flows.
表格内代码:

Command Description

git status List all new or modified files
表格作为布局工具 (不推荐): 不应滥用表格做文档布局。

Syntax	Description
Header	Title
Paragraph	Text

Left-aligned
Content

Right-aligned
Content

Center-aligned
Content

Left	Center	Right
A	B	C

Italic	Bold	`Code`
Cell 1	Cell 2	Cell 3

Col 1	Col 2
Data
	Data

Short	Long Text Column
A	This is a very long piece of text that will wrap within the table cell to demonstrate how content flows.

Command	Description
`git status`	List all new or modified files

七、其他 GFM 特有功能 (81-100)

提及用户 (@): @github

Please review this PR, @Reviewer.
引用 Issue 或 Pull Request (#): #1

Fixes #1
引用特定提交 (SHA): 6a5b3f1

The bug was fixed in 6a5b3f1.
表情符号 (Emoji) (使用别名): :smile:

This is great! 😄
表情符号 (使用 Unicode): 😀

Look, a smiley face! 😀
Strikethrough in Tables:

Feature Status

Old feature ~~Deprecated~~
Task Lists in Comments:
- Understand task lists
- Close the issue
Shorthand for Web URLs: 自动识别 https://example.com

Visit https://example.com for more info.
Highlighting (Fenced Code Blocks): 见第58条，语法高亮是其重要功能。

Feature	Status
Old feature	~~Deprecated~~

Diff Formatting in Code Blocks:

+ Added line
- Removed line

+ Added line
- Removed line

折叠细节 (HTML Details/Summary):
Mermaid 图表 (在支持的环境中):
```
graph TD;
    A-->B;
    A-->C;
```
警告提示框 (HTML Block):
行内 HTML: <strong>HTML bold</strong>

Use if needed.
HTML 换行: <br>

First LineSecond Line
HTML 分区: <div>...</div>

<div align="right">Right-aligned content.</div>
脚注 (非标准GFM, 部分平台支持): [^1]

This is a sentence with a footnote.¹
定义列表 (非标准GFM): 通常需用HTML <dl>, <dt>, <dd>。
数学公式 (LaTeX, 非标准GFM): $\sqrt{3}$ ，GitHub本身不直接渲染，但可在支持的编辑器或CI/CD流程中处理。
YAML Front Matter: (用于 Jekyll 等静态博客)
```
---
title: My Page
---
```
(放置在Markdown文件最顶部)

This is the footnote definition. ↩

史上最全面的 Markdown 语法总览终极参考！

一、 基本文本格式 (1-15)

This is an H1

This is an H2

H1

H2

H3

H4

H5

H6

二、 列表 (16-30)

三、 链接与图片 (31-45)

四、 引用与水平线 (46-55)

A heading in a blockquote

五、 代码 (56-70)

六、 表格 (GFM 扩展, 71-80)

七、 其他 GFM 特有功能 (81-100)

Footnotes

一、基本文本格式 (1-15)

二、列表 (16-30)

三、链接与图片 (31-45)

四、引用与水平线 (46-55)

五、代码 (56-70)

六、表格 (GFM 扩展, 71-80)

七、其他 GFM 特有功能 (81-100)