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+# CodeDrill
+
+[简体中文](README.md) | English
+
+[](https://github.com/anyuer678/codedrill/actions/workflows/test.yml)
+
+> **Status**: `portfolio` · Offline programming training system · **Platform completeness varies** (local/Windows builds are primary)
+> Known issues and scope are tracked in the rest of this README and in Issues; the training core (transcription / fill-in / bug-fix + SRS) runs locally.
+> The online Pages preview has limited functionality (see note below).
+
+
+[](https://anyuer678.github.io/codedrill/)
+> ⚠️ **Limited online preview**: some interactions (offline training-data persistence, TTS speech synthesis, Android/iOS native features) are unavailable on GitHub Pages static hosting. Download the installer for the full experience.
+
+**Offline programming training system** — final edition
+
+Runs on Web, Windows, and Android. Build programming muscle memory through code transcription, fill-in-the-blank, and bug-fix exercises.
+
+
+
+
+## Features
+
+### Training modes
+- **Code transcription** — copy code as shown to internalize syntax structure and style
+- **Fill in the blank** — complete missing code fragments to strengthen recall
+- **Bug fixing** — find and fix broken code to sharpen debugging skills
+
+### Languages
+Java, Python, C++, JavaScript, TypeScript, Linux Shell, SQL
+
+### Training modules
+Loops, conditionals, array operations, string processing, function calls
+
+### UI & themes
+- 22 light themes (solid / gradient / paper texture / ink-wash styles)
+- Responsive design for desktop and mobile
+
+### Learning system
+- **Training history** — local localStorage: list / clear / export JSON (capped at 500 records, no cloud sync)
+- **Achievements** — unlock achievements by hitting goals
+- **Skill tree** — visual progress of skill mastery
+- **Spaced repetition** — Ebbinghaus-curve-based smart review
+
+## Quick start
+
+### Requirements
+- Node.js >= 18.0.0
+- npm or yarn
+
+### Install & run
+```bash
+# clone the project
+git clone
+cd codedrill
+
+# install dependencies
+npm install
+
+# start the dev server
+npm run dev
+# or use the PowerShell script
+.\start.ps1
+```
+
+Open http://localhost:3000 to view the app
+
+## Building
+
+### Interactive build
+```bash
+.\build.ps1 # interactively pick a build target
+```
+
+### CLI build
+```bash
+npm run build:www # build the web version → dist/web/
+npm run build:apk # build the Android APK
+npm run build:exe # build the Windows portable EXE
+npm run build:all # build all platforms
+```
+
+### Build outputs
+- **Web**: `dist/web/` — deployable to any static server
+- **Windows**: `dist/electron-build/CodeDrill-便携版.exe` — no install needed, double-click to run
+- **Android**: `android/app/build/outputs/apk/` — sign before installing
+
+## Tech stack
+
+| Layer | Technology |
+|------|------|
+| Frontend | Vue 3 |
+| State | Pinia |
+| Routing | Vue Router |
+| Build | Vite |
+| Desktop | Electron + electron-builder |
+| Mobile | Capacitor (Android) |
+| Testing | Vitest |
+
+## Platform support
+
+| Platform | Format | Status |
+|------|------|------|
+| Web | HTML/CSS/JS | ✅ Fully supported |
+| Windows | EXE portable | ✅ Fully supported |
+| Android | APK | ✅ Fully supported |
+
+## Project structure
+
+```
+codedrill/
+├── src/ # Vue 3 frontend source
+│ ├── views/ # page components (home, training, stats, etc.)
+│ ├── stores/ # Pinia stores (questions, progress, settings)
+│ ├── components/ # shared components (cards, buttons, dialogs, etc.)
+│ ├── design-system/ # design system (themes, colors, fonts)
+│ ├── router/ # route config
+│ ├── data/ # static data
+│ └── lib/ # utility functions
+├── core/ # question bank data
+│ ├── questions/ # 635 built-in questions (35 JSON banks)
+│ └── bosses/ # boss-level data
+├── public/ # static assets (theme art, icons)
+├── electron/ # Electron main process
+│ ├── main.js # main process entry
+│ └── preload.js # preload script
+├── android/ # Android project (Capacitor)
+├── dist/ # build output
+│ ├── web/ # web build
+│ └── electron-build/ # Windows build
+├── scripts/ # helper scripts
+├── docs/ # project docs
+├── index.html # entry HTML
+├── vite.config.js # Vite config
+├── electron-builder.config.mjs # Electron packaging config
+├── package.json # project config
+├── start.ps1 # dev startup script
+└── build.ps1 # build script
+```
+
+## Development status
+
+> **Training history (shipped)**: a **minimal stable storage** is live (localStorage + list/clear/export JSON) with unit tests.
+> The **full UI/architecture "complete rewrite" is frozen** — out of scope; if it ever happens it will get a new Issue and does not block existing features.
+
+### History capabilities & limits (honest statement)
+
+| Capability | Status | Notes |
+|------|------|------|
+| List / filter / pagination | ✅ | `/history` page; filter by mode and language |
+| Export JSON | ✅ | History or Settings page; includes schemaVersion and limits |
+| Export CSV / full JSON backup | ✅ | Settings → "Data management" |
+| Import JSON backup | ✅ | Settings page |
+| Clear history / wipe all data | ✅ | History → "Clear history"; Settings → "Erase all data" |
+| Persistence backend | localStorage | `codedrill_history` / `codedrill_stats`, capped at **500** records |
+| Cloud sync / accounts | ❌ Not implemented | Data is lost if you switch browsers or clear site data; export backups yourself |
+| IndexedDB / SQLite | ❌ Not implemented | Architecture frozen; no promises |
+| Electron/Android native file storage | ❌ Not implemented | Currently shares WebView localStorage with Web |
+
+## Platform completeness matrix (honest statement)
+
+| Platform | Status | Training core | History | Notes |
+|------|------|----------|----------|------|
+| Web / local browser | Main path | ✅ | ✅ localStorage | Vite build; previewable on GitHub Pages, history follows browser storage |
+| Windows (Electron) | Buildable | ✅ | ✅ same Web localStorage | `electron/` + `electron-builder`; portable; icon see Issue #3 |
+| Android (Capacitor) | Skeleton/partial | ⚠️ verify locally | ⚠️ WebView localStorage | `android/` and Capacitor config exist; **no promise** of store-grade APK |
+| iOS | Not promised | ❌ | ❌ | This README claims nothing for iOS |
+| Cloud sync / multi-device | Not implemented | — | ❌ | No backend account system |
+
+> Matrix principle: only claim what is reproducible locally/CI; avoid "✅ fully supported" style over-claiming.
+
+## Known issues (tracked in Issues)
+
+- Theme asset build parsing → Issue #2 (closed)
+- Electron app icon → Issue #3 (closed)
+- SRS/scoring core tests → Issue #4 (closed)
+- History "complete rewrite" → **frozen**; current minimal stable storage above (scope & honesty tracked in Issue #1)
+
+
+## Disclaimer
+
+This project is for learning, exchange, and demonstration purposes only; it is not a commercial service and carries no technical guarantees. The software is provided "AS IS" with no express or implied warranties. Defects and issues found during use may be reported via [GitHub Issues](https://github.com/anyuer678/codedrill/issues), but the author accepts no liability for any loss arising directly or indirectly from using this software.
+
+## License
+
+Licensed under the [GNU General Public License v3.0](LICENSE).
+
+### License highlights
+- ✅ Free to use, modify, and distribute
+- ⚠️ Derivative works must be licensed under the same license (GPL v3)
+- ❌ Closed-source commercialization prohibited
diff --git a/README.md b/README.md
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--- a/README.md
+++ b/README.md
@@ -1,4 +1,5 @@
# CodeDrill
+[English](README.en.md) | 简体中文
[](https://github.com/anyuer678/codedrill/actions/workflows/test.yml)