Posture Reminder

The Posture Reminder fires a desktop browser notification at a fixed interval telling you to check your posture. It uses the browser's Notification API — when started, it requests permission (if not already granted) and counts down in seconds from the chosen interval. When the countdown reaches zero, it shows a 'Check your posture!' notification and restarts the timer.

1. Click the Start button — your browser will ask for notification permission; click Allow. 2. The countdown (mm:ss) begins from your configured interval (default 30 minutes). 3. When the timer hits 00:00, a system notification appears. 4. Click the Stop button to cancel the timer and silence further reminders.

The reminder interval is fixed at 30 minutes (intervalMinutes × 60 seconds). The timer runs inside a setInterval that ticks every 1 second and decrements the countdown; when it reaches 1, it constructs a new Notification titled with the localized status and body 'Check your posture!', then resets the countdown to the full interval. Notifications only appear when the page tab is open and Notification.permission is 'granted'.