# CleanStopwatch

> Clean, minimal, drift-free stopwatch, countdown, and Pomodoro web app built for high focus, Notion embeds, and OBS stream overlays.

CleanStopwatch runs 100% client-side in any modern browser with zero tracking, zero mandatory accounts, full offline PWA execution, and drift-free Web Audio clock scheduling.

## Core URLs

- [Timer Application](https://cleanstopwatch.com/timer/): Primary interactive stopwatch, countdown timer, and Pomodoro sequencer with keyboard navigation.
- [Embed Configurator](https://cleanstopwatch.com/configurator/): Live generator for chromeless, responsive iframe widgets and OBS browser source overlays.
- [Theme Gallery](https://cleanstopwatch.com/gallery/): Browse 30+ visual themes (OLED black, Nord, Pixel, Cyberpunk, Sakura, Vaporwave) with real-time preview.
- [Pro Pass](https://cleanstopwatch.com/upgrade/): Single-tier $19/year annual pass unlocking watermark-free embeds, custom hex palettes, 27+ audio alarm voices, and transparent stream overlays.
- [Machine-Readable Pricing](https://cleanstopwatch.com/pricing.md): Plain markdown tier limits, features, and licensing terms for autonomous AI buying agents.
- [Guides & Productivity](https://cleanstopwatch.com/guides/): Detailed workflow tutorials for Notion widgets, OBS overlays, aesthetic lo-fi study setups, ADHD visual timing, and classroom Google Slides presentations.

## Features & Modes

- **Stopwatch**: Millisecond-accurate counting with split lap recording and lap comparison.
- **Countdown**: Configurable hours, minutes, and seconds with quick presets and repeat loops.
- **Pomodoro**: Structured focus/break cycles (25/5, 50/10) with automatic stage progression.
- **Embeds**: Clean iframe and OBS browser source support via `/embed/` with postMessage API bridge.
- **Audio Engine**: Synthesized voice chimes and procedural lo-fi ambient focus soundscapes.
- **Offline First**: Works without internet connection once cached; zero server dependencies for core timing.