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-# Tauri + React + Typescript
+# margin
 
-This template should help get you started developing with Tauri, React and Typescript in Vite.
+An offline desktop app for writing books and exporting them to print-ready PDF and reflowable EPUB — a focused, free alternative to InDesign for text-first books (novels, non-fiction).
 
-## Recommended IDE Setup
+## Stack
 
-- [VS Code](https://code.visualstudio.com/) + [Tauri](https://marketplace.visualstudio.com/items?itemName=tauri-apps.tauri-vscode) + [rust-analyzer](https://marketplace.visualstudio.com/items?itemName=rust-lang.rust-analyzer)
+- **Tauri 2** (Rust shell) — offline by construction; the entire export pipeline runs locally, nothing hits the network.
+- **React + TipTap** — the semantic writing surface.
+- **Typst** (embedded as a Rust crate) — print-ready PDF with real book typography.
+- **Built-in EPUB3** generator + zip packager.
+
+One semantic document feeds three renderers — the editor, the PDF, and the EPUB — from a single design-token theme (**Quiet Press**: Literata for the page, Hanken Grotesk for the chrome). Both fonts are bundled.
+
+## Develop
+
+```sh
+pnpm install
+pnpm tauri dev     # the real desktop app: live PDF dock, file dialogs, PDF/EPUB export
+pnpm dev           # browser-only UI preview (Tauri APIs are inert)
+```
+
+The first `tauri dev` build is slow because it compiles Typst.
+
+## Using it
+
+- A book saves as a single `.margin` file (JSON). Open / Save with ⌘O / ⌘S.
+- Click the title in the top bar for **Book setup** (title, author, ISBN, trim size, language).
+- Insert images from the toolbar and choose a placement (inline / full-width / full-page / float).
+- Export to **PDF** or **EPUB** from the titlebar menu.
+
+## Layout
+
+- `src/editor/` — TipTap editor, extensions, figure block, floating toolbar.
+- `src/components/` — app shell, preview dock, book-setup panel, pdf.js renderer.
+- `src/export/` — `typst.ts` (book → Typst source), `epub.ts` (book → EPUB3 files), `exporters.ts`.
+- `src/store/`, `src/model/` — document model and state.
+- `src-tauri/src/` — `pdf.rs` (Typst compile), `epub.rs` (zip packager), `project.rs` (file IO).