---
id: TASK-135
title: PWA — offline support (SW + IndexedDB)
status: Done
assignee: []
created_date: '2026-03-29 20:52'
labels:
  - pwa
  - offline
milestone: m-2
dependencies: []
priority: medium
---

## Description

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Write sw.js (service worker with 3 cache buckets: shell/guides/mediapipe, cache-first for shell+CDN, network-first for guides, offline fallback) and manifest.json (PWA install metadata).
<!-- SECTION:DESCRIPTION:END -->

## Acceptance Criteria
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- [ ] #1 Three versioned cache buckets
- [ ] #2 Shell pre-cached on install, old caches cleaned on activate
- [ ] #3 CACHE_GUIDE_URL message handler for dynamic guide caching
- [ ] #4 Offline fallback: cached index.html for nav, error JSON for guides
- [ ] #5 PWA manifest with standalone display and portrait orientation
<!-- AC:END -->

## Final Summary

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sw.js (210 lines): 3 cache buckets, pre-cache on install, clients.claim(), offline fallback. manifest.json with simulator shortcut.
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