diff --git a/CHANGELOG.md b/CHANGELOG.md
index bbe21e5..6cf8c27 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -8,6 +8,8 @@ Follows [Keep a Changelog](https://keepachangelog.com/en/1.0.0/) · versioned wi
## [Unreleased]
### Changed
+- **Resource diagnostics stylesheet split.** Performance-panel styles now live in `static/css/resource-diagnostics.css`
+ and are loaded with the same release cache-busting version as the core stylesheet.
- **Audiobook cast export extraction.** Markdown serialization and legacy page-stamping migration now live in
`audiobook-cast.js`, leaving the live casting workflow in `audiobook.js` and preserving the same global helpers.
- **Rehearser training extraction.** Transcript normalization, LCS matching, and word-level comparison now live in
diff --git a/TODO.md b/TODO.md
index b7bf8aa..6b0d299 100644
--- a/TODO.md
+++ b/TODO.md
@@ -136,6 +136,7 @@ architecture change: the larger Audiobook/Rehearser/style split.
- [ ] Extract Audiobook parsing and casting.
- [x] Extract Audiobook parsing primitives and speaker-heuristic constants into `audiobook-parse.js`.
- [x] Extract Audiobook cast serialization and page-stamping helpers into `audiobook-cast.js`.
+- [x] Split the Performance/resource diagnostic styles into `static/css/resource-diagnostics.css`.
- [ ] Split `style.css` by feature.
- [ ] Do not migrate to TypeScript or rewrite the frontend until behavior is covered by tests.
diff --git a/VERSION b/VERSION
index 7388294..a122672 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-1.24.33
+1.24.34
diff --git a/docs/ARCHITECTURE.md b/docs/ARCHITECTURE.md
index d666ffc..a8e7f72 100644
--- a/docs/ARCHITECTURE.md
+++ b/docs/ARCHITECTURE.md
@@ -36,6 +36,7 @@ Done incrementally as global-scope ordered files (no ES-module change needed)
- ✅ `rehearser-cast.js` — cast view, sort/filter state handlers, and cast toolbar wiring; card rendering remains in `rehearser.js`.
- ✅ `audiobook-parse.js` — dialogue detection, dehyphenation, and speaker-heuristic constants; the casting pipeline remains in `audiobook.js`.
- ✅ `audiobook-cast.js` — cast Markdown export and legacy page-stamping migration helpers; live casting remains in `audiobook.js`.
+- ✅ `static/css/resource-diagnostics.css` — isolated Performance/resource diagnostic panel styles.
- ✅ `rehearser-train.js` — transcript normalization, LCS comparison, and word-level training feedback; microphone/state wiring remains in `rehearser.js`.
- ✅ `rehearser-library.js` — SQLite persistence helpers and IndexedDB migration; import/export and auto-save remain
in `rehearser.js` until their UI/event-handler dependencies are isolated.
diff --git a/static/css/resource-diagnostics.css b/static/css/resource-diagnostics.css
new file mode 100644
index 0000000..8fe01ea
--- /dev/null
+++ b/static/css/resource-diagnostics.css
@@ -0,0 +1,6 @@
+/* ── Performance/resource diagnostics ─────────────────────────────────────── */
+.resource-diagnostics-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(130px, 1fr)); gap: 8px; }
+.resource-diagnostic-item { display: flex; flex-direction: column; gap: 3px; padding: 9px 10px; border: 1px solid var(--border); border-radius: 6px; background: var(--panel); }
+.resource-diagnostic-item span { color: var(--subtext); font-size: 11px; }
+.resource-diagnostic-item strong { font-size: 14px; }
+.resource-diagnostic-subhead { grid-column: 1 / -1; margin-top: 8px; color: var(--subtext); font-size: 12px; font-weight: 700; }
diff --git a/static/index.html b/static/index.html
index 45225db..50362ce 100644
--- a/static/index.html
+++ b/static/index.html
@@ -10,7 +10,7 @@
-
+
@@ -27,7 +27,8 @@
-
+
+
@@ -392,7 +393,7 @@ window.toggleNavTree = function(treeId, chevronId) {
-
+