readme update

README.md

@@ -1,6 +1,57 @@
 # numnum
 
-Numeral systems trainer in PWA app
+тренер систем счисления
 
-[Try it now](https://numnum.atroshin.ru)
+**Demo:** [numnum.atroshin.ru](https://numnum.atroshin.ru)
 
+## Features
+
+- 10 numeral systems: Binary, Ternary, Balanced Ternary, Octal, Hexadecimal, Braille Decimal, Roman, Church Slavonic, Greek, Hebrew
+- Two game modes: multiple choice and manual entry (numpad)
+- Configurable number range, time limit (1s–30s or no limit), question count (5–100)
+- Installable PWA with full offline support (theory content cached)
+- Dark/light theme · Bilingual (English / Русский)
+- In-app theory reference for each system
+
+## Usage
+
+Serve the directory with any HTTP server:
+
+```
+python3 -m http.server 8080
+```
+
+## Project structure
+
+```
+index.html       — Entry point
+app.js           — Game logic and UI
+numerals.js      — Numeral system converters and choice generator
+styles.css       — Styles, dark/light theme
+sw.js            — Service worker (PWA caching)
+manifest.json    — PWA manifest
+theory/          — Theory HTML files (10 systems × 2 languages)
+```
+
+## Supported systems
+
+| System | Type | Range |
+|---|---|---|
+| Binary | Positional | 1–32768 |
+| Ternary | Positional | 1–27 |
+| Balanced Ternary | Positional | –27–27 |
+| Octal | Positional | 1–4096 |
+| Hexadecimal | Positional | 1–65536 |
+| Braille Decimal | Positional | 0–9999 |
+| Roman | Non-positional | 1–3999 |
+| Church Slavonic | Non-positional | 1–9999 |
+| Greek | Non-positional | 1–9999 |
+| Hebrew | Non-positional | 1–9999 |
+
+## Development
+
+Theory HTML files live in `theory/`. After editing them, bump the version in `sw.js` to refresh the cache on next install.
+
+## License
+
+MIT