Syntax Guideline

Basic Text

Bold, italic, strikethrough, inline code, and links.

Blockquote:

“We don’t write because we want to; we write because we have to.” — and sometimes just so future-me doesn’t have to google it again.

Headings

# H1 — page title (used once)
## H2 — main section
### H3 — subsection
#### H4 — rarely needed

Lists

Unordered:

• First item
• Second item
  • Nested
  • Also nested

Ordered:

1. Build with Astro
2. Push to GitHub
3. Auto-deploy via GitHub Actions

Task list:

• Callouts
• Mermaid diagrams
• KaTeX math
• Runnable Python
• Write more posts

Footnotes work too¹.

Tables

Code Blocks

Plain block:

def fib(n):
    a, b = 0, 1
    for _ in range(n):
        a, b = b, a + b
    return a

With filename and line highlight:

export function greet(name: string): string {
  return `Hello, ${name}!`;  // highlighted line
}

Diff block:

export default defineConfig({
  output: 'server',
  output: 'static',
});

Callouts / Admonitions

Two syntaxes — ::: style:

GitHub-flavoured blockquote style:

Mermaid Diagrams

Flowchart:

flowchart LR
  A[Markdown] --> B{remark}
  B -->|directive| C[Admonition]
  B -->|mermaid| D[Diagram]
  B --> E[rehype + KaTeX]
  C & D & E --> F[(Static HTML)]

Sequence diagram:

sequenceDiagram
  participant U as Browser
  participant CDN
  U->>CDN: GET /blog/a-post
  CDN-->>U: Static HTML (prebuilt)
  Note over U,CDN: 0 server runtime

Math (KaTeX)

Inline: the average complexity of quicksort is $O(n \log n)$.

Euler’s identity: $e^{i\pi} + 1 = 0$.

Block — sigmoid function (used in logistic regression and neural nets):

Gaussian integral:

Interactive Chart

GitHub Repo Cards

Embed a repo with live star/fork counts:

Terminal Recording (Asciinema)

Runnable Python (Pyodide / WASM)

Code blocks with run execute right in the browser — no backend, no server. First run downloads the Pyodide runtime (~6 MB, cached afterwards).

print("Hello from Python, running in your browser!")

def fib(n):
    a, b = 0, 1
    for _ in range(n):
        a, b = b, a + b
    return a

print("First 10 Fibonacci numbers:")
print([fib(i) for i in range(10)])

Standard library is included:

import math, statistics

data = [3, 1, 4, 1, 5, 9, 2, 6, 5, 3, 5]
print("mean   :", round(statistics.mean(data), 3))
print("stdev  :", round(statistics.pstdev(data), 3))
print("sqrt 2 :", math.sqrt(2))

Errors are caught and displayed — try editing a block to raise one.

Encrypted Posts

Add a password field to any post’s frontmatter:

---
title: "Secret notes"
description: "..."
date: 2026-01-01
tags: [private]
password: mysecretpassword
---

At build time, the content is encrypted with AES-GCM (PBKDF2 key derivation, 150 000 iterations). The published HTML contains only ciphertext — the browser decrypts it on the correct password, without any server round-trip.