diff --git a/client/vite.config.js b/client/vite.config.js
index 79398cd20..c311e4118 100644
--- a/client/vite.config.js
+++ b/client/vite.config.js
@@ -24,11 +24,17 @@ export default defineConfig(({ mode }) => ({
         suppressWarnings: true,
       },
       workbox: {
-        // Anything above this is dropped from the precache manifest without failing
-        // the build, so the PWA would just be broken offline. Keep the ceiling close
-        // to the real bundle so growth shows up as a build warning instead. Revisit
-        // once route-level splitting lands and the entry chunk shrinks.
-        maximumFileSizeToCacheInBytes: 6 * 1024 * 1024,
+        // Anything above this is dropped from the precache manifest. The build does
+        // not fail over it, it only prints "won't be precached", so the ceiling has
+        // to sit close to the real bundle or an accidental heavyweight goes
+        // offline-broken unnoticed. Largest precached entry after route splitting is
+        // the heic-to chunk at 3.0 MB; the entry chunk is down to 1.2 MB.
+        maximumFileSizeToCacheInBytes: 3.5 * 1024 * 1024,
+        // Every route chunk is precached alongside the shell, deliberately: for an
+        // offline-first travel planner a route the user never opened before losing
+        // signal still has to work. The trade is that route splitting buys first
+        // paint and not install size — 107 entries / 17,795 KiB before the split,
+        // 178 / 17,826 KiB after.
         globPatterns: ['**/*.{js,css,html,svg,png,woff,woff2,ttf}'],
         // build:analyze drops a treemap next to the app; it must never end up in a
         // precache manifest if someone ships that build by accident.
diff --git a/wiki/Offline-Mode-and-PWA.md b/wiki/Offline-Mode-and-PWA.md
index babad5319..670576950 100644
--- a/wiki/Offline-Mode-and-PWA.md
+++ b/wiki/Offline-Mode-and-PWA.md
@@ -26,12 +26,15 @@ TREK uses Workbox service-worker caching plus an IndexedDB database (Dexie) for
 
 | Content | Cache name | Strategy | Duration | Max entries |
 |---------|------------|----------|----------|-------------|
-| CartoDB / OpenStreetMap map tiles | `map-tiles` | CacheFirst | 30 days | 1 000 |
-| API responses (trips, places, bookings, etc.) | `api-data` | NetworkFirst (5 s timeout) | 24 hours | 200 |
+| CartoDB / OpenStreetMap map tiles | `map-tiles` | CacheFirst | 30 days | 12 288 |
+| Mapbox GL style, glyphs, sprites and vector tiles | `mapbox-tiles` | StaleWhileRevalidate | 30 days | 3 000 |
+| OpenFreeMap MapLibre style and tiles | `openfreemap-tiles` | StaleWhileRevalidate | 30 days | 3 000 |
 | Cover images and avatars (`/uploads/covers`, `/uploads/avatars`) | `user-uploads` | CacheFirst | 7 days | 300 |
-| App shell (HTML / JS / CSS) | precache | Precached | Until next deploy | — |
+| App shell and every page of the app (HTML / JS / CSS) | precache | Precached | Until next deploy | — |
 
-> **Note:** The API cache excludes sensitive endpoints — `/api/auth`, `/api/admin`, `/api/backup`, and `/api/settings` are always fetched from the network.
+> **Note:** API responses are **never** stored in the service-worker cache. Workbox keys its entries by URL and cannot vary them on the session cookie, so on a shared device one account's cached data could be served to the next. Offline reads come from the per-user IndexedDB cache described below instead.
+
+> **Note:** The precache covers every page, not just the one you happen to open first. A page you have never visited still works after you lose connectivity — at the cost of a larger initial install.
 
 **IndexedDB (Dexie) — structured trip data**