Lumidown

# 👋 Welcome to Lumidown

Write Markdown on the left, see it rendered on the right. Everything happens **in your browser** 🔒: files you open are never uploaded, and your work is saved on this device as you type.

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- [✨ What you can do](#-what-you-can-do)
- [⚡ Markdown in 30 seconds](#-markdown-in-30-seconds)
- [🧮 Math](#-math)
- [📊 Diagrams](#-diagrams)
- [🖼️ Images](#️-images)
- [🎯 Tips](#-tips)
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## ✨ What you can do

- 📂 **Open** a `.md` file (File → Open, or drop it on the page) and save it back.
- 📥 **Import** a web page, a Google Doc or a Word file: paste rich text, or import `.html` / `.docx`.
- 📤 **Export** to PDF, Word (`.docx`) or a standalone HTML file.
- 🧹 **Tidy up** with the formatter, generate a table of contents, or build tables from spreadsheet data.

## ⚡ Markdown in 30 seconds

| You type | You get |
| :-- | :-- |
| `**bold**` | **bold** |
| `_italic_` | _italic_ |
| `[link](https://example.com)` | [link](https://example.com) |
| `- [ ] task` | a checkbox |
| `:tada: 🚀` | :tada: 🚀 |

```js
// Fenced code blocks are highlighted 🎨
const greet = (name) => `Hello, ${name}! 👋`;
```

> 💡 Blockquotes, footnotes[^1], ~~strikethrough~~ and task lists work too.

- [x] ✅ Try the editor
- [ ] 🚀 Export something

## 🧮 Math

Write formulas in LaTeX between dollar signs, like $E = mc^2$ in a sentence, or on their own between `$` lines:

$
\int_0^1 x^2\,dx = \frac{1}{3} \qquad \sum_{i=1}^{n} i = \frac{n(n+1)}{2}
$

$
\sqrt{a^2 + b^2} \qquad \lim_{x \to 0} \frac{\sin x}{x} = 1 \qquad \begin{pmatrix} 1 & 0 \\ 0 & 1 \end{pmatrix}
$

- 💵 Prices stay prices: a coffee at $3 and a cake at $5 are not formulas.
- 📝 **Export → Word** turns formulas into real equations you can edit in Word.

## 📊 Diagrams

Draw diagrams with [Mermaid](https://mermaid.js.org/) in a `` ```mermaid `` block — flowcharts, sequences, timelines, pie charts and more:

```mermaid
flowchart LR
    A[Markdown, Word or a web page] --> B(Lumidown)
    B --> C[Word]
    B --> D[PDF]
    B --> E[Slack, Teams, Discord]
```

```mermaid
sequenceDiagram
    You->>Lumidown: Paste an AI answer
    Lumidown-->>You: A clean Word document
```

```mermaid
flowchart TD
    Start([You receive a file]) --> Kind{What is it?}
    Kind -- .md or .txt --> Open[Open it or drop it here]
    Kind -- Word or a web page --> Import[Import it as Markdown]
    Kind -- An AI answer --> Paste[Paste it into the editor]
    Open & Import & Paste --> Edit[Read it, fix it, check it]
    Edit --> Share
    subgraph Share [Then share it]
        direction TB
        Word[Export to Word] ~~~ PDF[Export to PDF] ~~~ Chat[Copy for Slack, Teams or Discord] ~~~ Slides[Present it as slides]
    end
```

- 🖨️ They print sharp in PDF and HTML, and become pictures in Word.

## 🖼️ Images

![How it works: your file is opened, edited and exported in this browser, with nothing uploaded](images/how-it-works.png)

Set a **width** to make pictures smaller, or line several up side by side:

<img src="images/gallery-lake.jpg" alt="Lake at sunset" width="200"> <img src="images/gallery-forest.jpg" alt="Pine forest" width="200"> <img src="images/gallery-city.jpg" alt="City at night" width="200">

| Photo | Where | Best time |
| :-: | :-- | :-- |
| <img src="images/gallery-lake.jpg" alt="Lake" width="64"> | 🏞️ The lake | 🌅 Sunset |
| <img src="images/gallery-forest.jpg" alt="Forest" width="64"> | 🌲 The forest | ☀️ Morning |
| <img src="images/gallery-city.jpg" alt="City" width="64"> | 🌃 The city | 🌙 Night |

[![Sunset over purple mountains — click to open the Markdown Guide](images/welcome-sample.jpg)](https://www.markdownguide.org/basic-syntax/#images-1)

_🔗 Images can be links too: click the picture above._

- 📋 **Paste a screenshot** with Ctrl V, or 📥 **drop pictures** straight onto the editor.
- ➕ Or use the **Image** button: choose files or link a web address, with alt text and an optional width.
- 📐 Large photos are shrunk to 1600 px wide, and WebP / HEIC become JPEG, so documents stay light.
- 💾 Images are kept **in this browser** under `images/`, like a folder next to your file. **File → Download .zip** saves the document together with its images; Word and HTML exports embed them.

## 🎯 Tips

- ⌨️ **Ctrl B**, **Ctrl I**, **Ctrl K** — bold, italic, link.
- 💾 **Ctrl S** saves back to the file you opened (Chrome, Edge), or downloads it elsewhere.
- 📋 **Ctrl Shift V** pastes plain text instead of converting rich text.
- 😀 Type emoji directly, or use GitHub shortcodes like `:smile:` → :smile:

[^1]: Like this one 👆