chore: migrate PDF Tools to LocalToolBox

Reviewed-on: zemion/pdf-tools#3

.gitignore

@@ -141,3 +141,7 @@ vite.config.ts.timestamp-*
 .vite/
 
 todo.txt
+chatgpt_continuation.md5
+
+# Generated release artifacts
+release/

.npmrc

@@ -0,0 +1 @@
+@add-ideas:registry=https://git.add-ideas.de/api/packages/lotobo/npm/

CHANGELOG.md

@@ -4,6 +4,83 @@ All notable changes to `pdf-tools` are documented here.
 
 The project follows a pragmatic versioning scheme while the app is still below `1.0.0`: minor versions mark coherent user-facing milestones; patch versions mark fixes and small improvements.
 
+## 0.4.4 — LocalToolBox organization migration
+
+### Changed
+
+- Moved canonical repository, Toolbox schema, corresponding-source, and package-registry URLs from the personal `zemion` namespace to the `lotobo` LocalToolBox organization.
+- Upgraded the Toolbox contract, React shell, and validation testkit to `0.2.3` from the organization-owned registry.
+- Bumped the app/package version to `0.4.4`.
+
+## 0.4.3 — Aligned Toolbox content width
+
+### Changed
+
+- Expanded the PDF workspace's maximum content width from `900px` to `90rem` so it aligns with the shared Toolbox shell bar and central catalogue.
+- Bumped the app/package version to `0.4.3`.
+
+## 0.4.2 — Corrected Toolbox header orientation
+
+### Changed
+
+- Upgraded the Toolbox contract, React shell, and validation testkit to `0.2.2`.
+- Moved the Toolbox icon and `add·ideas Toolbox` label to the fixed far-left block, kept the app title and one tagline centered, and moved the fixed control cluster to the far right in the reverse order: Help, the PDF-specific Gitea source link, Apps, and Personalize.
+- Bumped the app/package version to `0.4.2`.
+
+## 0.4.1 — Stable Toolbox header layout
+
+### Changed
+
+- Upgraded the Toolbox contract, React shell, and validation testkit to `0.2.1`.
+- Adopted the stable shared top bar: the fixed left cluster contains Personalize, Apps, the PDF-specific Gitea source link, and Help; the app title and one tagline remain centered; and the fixed far-right block contains the Toolbox icon and `add·ideas Toolbox` label.
+
+## 0.4.0 — Shared Toolbox header and themes
+
+### Added
+
+- Added the standard Toolbox header controls for in-app help, the app-specific Gitea source link, appearance personalization, and application switching.
+- Added explicit light, dark, and system-following themes for the PDF workspace, saved-workspace list, merge queue, dialogs, status messages, and controls.
+
+### Changed
+
+- Upgraded the Toolbox contract, React shell, and validation testkit to `0.2.0`.
+- The header now uses the manifest's repository metadata for the source link instead of carrying a release-specific source action.
+- Replaced application color literals with semantic PDF workspace variables while intentionally keeping rendered PDF pages on a white paper surface.
+- Scoped application button and card styles to the shell's main content so they cannot override shared header controls.
+- Bumped the app/package version to `0.4.0`.
+
+## 0.3.4 — PDF.js compatibility and Toolbox integration
+
+### Added
+
+- Added a generated Toolbox App Contract manifest and shared Toolbox Shell integration with standalone fallback.
+- Added deterministic, checksummed release ZIP packaging for artifact-based toolbox assembly.
+
+### Changed
+
+- Centralized PDF.js setup in a shared module so thumbnail rendering and page preview use the same legacy PDF.js build and worker configuration.
+- Added a local PDF.js worker wrapper that installs a `Uint8Array.prototype.toHex` compatibility shim before PDF.js worker code runs.
+- Added the same `toHex` compatibility shim in the main app bundle for browsers that do not provide it natively.
+- Made Vite asset URLs relative so the app can be hosted at arbitrary nested paths.
+- Corrected the documented licence identifier to `AGPL-3.0-only`.
+- Bumped the app/package version to `0.3.4`.
+
+## 0.3.2 — Multi-file merge queue release
+
+### Added
+
+- Added a multi-file merge queue for selecting, loading, reviewing, reordering, removing, and merging several incoming PDFs.
+- Added queue merge modes for replacing the current document, appending after the current workspace, or inserting at a chosen one-based page position.
+- Added merge queue helper tests for queue ordering, readiness checks, insert-position clamping, and merged filename generation.
+- Added PDF merge service tests for queue-only and base-plus-incoming merge results.
+
+### Changed
+
+- Changed the file picker to accept multiple PDFs. A single file with no active workspace still opens directly; otherwise selected files are added to the merge queue.
+- Replaced the old single-file merge card with a queue-based merge panel.
+- Merging now creates a new unsaved workspace from the materialized merge result, preserving the current workspace state before append/insert merges.
+- Bumped the app/package version to `0.3.2`.
+
 ## 0.3.1 — Split ZIP export release
 
 ### Added

README.md

@@ -4,7 +4,9 @@
 
 Current hosted version: <https://pdftools.add-ideas.de>
 
-Current release: **v0.3.1 — Split ZIP export release**. See [`CHANGELOG.md`](CHANGELOG.md) for release notes and milestone history.
+Current development release: **v0.4.4 — LocalToolBox organization migration**. See [`CHANGELOG.md`](CHANGELOG.md) for milestone history.
+
+Active work is tracked in Gitea issues. Durable project context is mirrored into the Gitea wiki from repository docs, including [`ROADMAP.md`](ROADMAP.md).
 
 The app is a static React/Vite single-page application. There is no backend service, no server-side queue, and no server-side document storage. When hosted correctly, the server only delivers HTML, JavaScript, CSS, and static assets; PDF processing happens in the user's browser.
 
@@ -40,6 +42,8 @@ This makes the project especially useful for self-hosted environments, public-se
 - **Thumbnail cache by page and rotation**: Rotated thumbnails are cached and only changed thumbnails need to be regenerated.
 - **Stable page references**: Duplicated pages and reordered pages are tracked as workspace page references rather than only by original page number.
 - **Merge choices**: Loading another PDF can replace the current document, append pages, or insert pages at a chosen position.
+- **PDF.js compatibility setup**: PDF.js is configured through one shared module and a local worker wrapper so the app can polyfill `Uint8Array.prototype.toHex` before PDF.js runs in older browsers.
+- **Toolbox appearance controls**: The shared header provides light, dark, and system-following themes and keeps the app switcher, help, and source controls in the same place as the Toolbox portal.
 - **In-app help**: The app includes a Help/Tutorial dialog with keyboard shortcuts and workflow explanations.
 
 ## Current features
@@ -93,7 +97,7 @@ Keyboard shortcuts are ignored while typing in form fields.
 
 ## In-app documentation concept
 
-The app includes a Help/Tutorial dialog reachable from the header via **Help ?**, `F1`, or `?`.
+The app includes a Help/Tutorial dialog reachable from the header's **?** control, `F1`, or `?`.
 
 Recommended structure for in-app documentation:
 
@@ -117,6 +121,18 @@ browser  <-- HTTPS -->  static web server / reverse proxy  -->  built app assets
 
 There is no application server to operate. Administrators only need to host the built files from `dist/`.
 
+The production build is relocatable and can also be assembled into an
+[Add Ideas Toolbox](https://git.add-ideas.de/lotobo/toolbox-portal) deployment.
+`toolbox-app.json` describes this app through the framework-independent
+[Toolbox App Contract](https://git.add-ideas.de/lotobo/toolbox-sdk). The same
+artifact remains fully usable on its own.
+
+The shared first-party shell always provides help, source, and appearance
+controls. When launched with a same-origin catalogue URL, for example
+`?toolbox=/toolbox.catalog.json`, it also connects the application switcher to
+the current Toolbox catalogue. Missing, invalid, and cross-origin catalogues
+are ignored so the app falls back to standalone mode.
+
 ### Build and test from source
 
 ```bash
@@ -135,6 +151,19 @@ npm run build
 
 The production build is written to `dist/`.
 
+Create a versioned, checksummed release artifact with:
+
+```bash
+npm run release:artifact
+```
+
+This writes `release/pdf-tools-<version>.zip` and its `.sha256` file. The ZIP
+contains the static app, its toolbox manifest and changelog, plus the application
+source-code location, license, and the full license/notice texts found for
+bundled runtime dependencies under `LICENSES/`. Existing artifacts for the same
+version are never replaced implicitly; after intentionally reviewing a rebuild, use
+`npm run release:artifact -- --force`.
+
 Useful individual development commands:
 
 ```bash
@@ -219,7 +248,7 @@ The app expects modern browser APIs, including:
 - Canvas;
 - modern JavaScript modules.
 
-Use current versions of Chromium, Firefox, Safari, or Edge.
+The app includes a small `Uint8Array.prototype.toHex` compatibility shim for PDF.js fingerprint handling in browsers that do not provide that typed-array helper natively. Use current versions of Chromium, Firefox, Safari, or Edge where possible.
 
 ## Versioning and release baseline
 
@@ -228,10 +257,10 @@ The application version shown in the header is defined in `src/version.ts`. The
 The current development baseline is:
 
 ```text
-v0.3.1 — Split ZIP export release
+v0.4.4 — LocalToolBox organization migration
 ```
 
-This release preserves the browser-only workspace baseline and adds split-result ZIP downloads on top of the selection-workspace feature. Workspace state, thumbnail handling, generated download URLs, page-grid components, tests, type-checking, linting, and formatting are separated enough to support additional feature work without turning `App.tsx` back into a monolith.
+This branch preserves the browser-only workspace baseline and PDF.js compatibility setup while using Toolbox SDK `0.2.3` from the `lotobo` package registry. The displayed app/package version is `0.4.4`; canonical source, schema, and release links use the LocalToolBox organization. The shared header keeps the Toolbox icon and `add·ideas Toolbox` label in a fixed far-left block, the app title and one tagline centered, and Help, the PDF source link, Apps, and Personalize in a fixed far-right cluster. The PDF workspace shares the shell bar's `90rem` maximum width. Workspace state, thumbnail handling, generated download URLs, page-grid components, tests, type-checking, linting, and formatting remain separated enough to support additional feature work without turning `App.tsx` back into a monolith.
 
 ## Project structure
 
@@ -248,6 +277,9 @@ src/
     ReorderPanel.tsx              Page grid, selection, drag/drop, copy/delete/rotate
     WorkspacePanel.tsx            Workspace save/load/reset and undo/redo history
   pdf/
+    pdfJs.ts                      Shared pdf.js setup and worker configuration
+    pdfjsWorker.ts                Local pdf.js worker wrapper with compatibility shim
+    uint8ArrayToHexPolyfill.ts    Compatibility shim for PDF.js fingerprint handling
     pdfService.ts                 pdf-lib operations: load, merge, split, export
     pdfThumbnailService.ts        pdf.js thumbnail rendering
     pdfZipService.ts              Browser-side ZIP packaging for split results
@@ -260,68 +292,10 @@ src/
   version.ts                      App version displayed in the header
 ```
 
-## Roadmap
+## Roadmap and backlog
 
-### Milestone 1: Fast preview and thumbnails
+The roadmap and non-goals now live in [`ROADMAP.md`](ROADMAP.md). Open roadmap items are imported into Gitea issues so priorities, status, and implementation notes stay out of the README.
-
-- [x] Remove unused legacy page list view.
-- [x] Bound thumbnail generation by width and height.
-- [x] Display thumbnails progressively.
-- [x] Add preview page flipping.
-- [x] Attach preview controls to the modal container.
-- [x] Add first keyboard shortcuts.
-- [x] Cache thumbnails by page and rotation.
-- [x] Regenerate only changed rotated thumbnails.
-- [x] Show software version number.
-
-### Milestone 2: Real page workspace
-
-- [x] Introduce stable page references instead of only original page indices.
-- [x] Support duplicate selected pages.
-- [x] Save and reload the last state from browser storage.
-- [x] Support named workspaces.
-- [x] Store PDF binaries directly in IndexedDB.
-- [x] Reset workspace.
-- [x] Add command history as a foundation for undo/redo.
-- [x] Add undo/redo.
-- [x] Display undo/redo history with redo entries visually separated.
-- [x] Extract selection as a new active workspace.
-- [ ] Reduce undo/redo storage footprint if large documents make snapshots too heavy.
-- [ ] Add grid/list view toggle.
-
-### Milestone 3: Better merge and mobile handling
-
-- [ ] Add a full multi-file merge queue.
-- [ ] Support drag-and-drop of PDFs into the page grid at the hovered position.
-- [ ] Add custom long-press drag on mobile.
-- [ ] Consolidate frequently used actions into a toolbar.
-
-### Milestone 4: Structural PDF editing
-
-- [ ] Metadata editing.
-- [ ] Crop pages.
-- [ ] Add tools directly in the preview overlay.
-- [ ] Read/fill/flatten forms.
-- [ ] Read bookmarks, then evaluate bookmark editing.
-- [ ] Read annotations, then evaluate annotation writing.
-
-### Milestone 5: Export and power tools
-
-- [ ] Basic text extraction.
-- [x] ZIP export for split results.
-- [ ] Optimize/compress MVP.
-- [ ] Carefully scoped encrypted PDF handling.
-
-## Non-goals for now
-
-- Server-side PDF processing.
-- Collaborative editing.
-- User accounts.
-- OCR.
-- Full content-stream editing.
-- Digital signature creation/validation workflows.
-- DMS replacement functionality.
 
 ## License
 
-GPL-3.0. See `LICENSE`.
+AGPL-3.0-only. See `LICENSE`.

ROADMAP.md

@@ -0,0 +1,63 @@
+# pdf-tools Roadmap
+
+Active roadmap items are tracked as Gitea issues. This file is kept as the source for issue import and wiki sync; completed items remain here as release context.
+
+## Milestone 1: Fast preview and thumbnails
+
+- [x] Remove unused legacy page list view.
+- [x] Bound thumbnail generation by width and height.
+- [x] Display thumbnails progressively.
+- [x] Add preview page flipping.
+- [x] Attach preview controls to the modal container.
+- [x] Add first keyboard shortcuts.
+- [x] Cache thumbnails by page and rotation.
+- [x] Regenerate only changed rotated thumbnails.
+- [x] Show software version number.
+
+## Milestone 2: Real page workspace
+
+- [x] Introduce stable page references instead of only original page indices.
+- [x] Support duplicate selected pages.
+- [x] Save and reload the last state from browser storage.
+- [x] Support named workspaces.
+- [x] Store PDF binaries directly in IndexedDB.
+- [x] Reset workspace.
+- [x] Add command history as a foundation for undo/redo.
+- [x] Add undo/redo.
+- [x] Display undo/redo history with redo entries visually separated.
+- [x] Extract selection as a new active workspace.
+- [ ] Reduce undo/redo storage footprint if large documents make snapshots too heavy.
+- [ ] Add grid/list view toggle.
+
+## Milestone 3: Better merge and mobile handling
+
+- [x] Add a full multi-file merge queue.
+- [ ] Support drag-and-drop of PDFs into the page grid at the hovered position.
+- [ ] Add custom long-press drag on mobile.
+- [ ] Consolidate frequently used actions into a toolbar.
+
+## Milestone 4: Structural PDF editing
+
+- [ ] Metadata editing.
+- [ ] Crop pages.
+- [ ] Add tools directly in the preview overlay.
+- [ ] Read/fill/flatten forms.
+- [ ] Read bookmarks, then evaluate bookmark editing.
+- [ ] Read annotations, then evaluate annotation writing.
+
+## Milestone 5: Export and power tools
+
+- [ ] Basic text extraction.
+- [x] ZIP export for split results.
+- [ ] Optimize/compress MVP.
+- [ ] Carefully scoped encrypted PDF handling.
+
+## Non-goals for now
+
+- Server-side PDF processing.
+- Collaborative editing.
+- User accounts.
+- OCR.
+- Full content-stream editing.
+- Digital signature creation/validation workflows.
+- DMS replacement functionality.

eslint.config.mjs

@@ -43,7 +43,7 @@ export default tseslint.config(
     },
   },
   {
-    files: ['*.config.{js,ts}', 'eslint.config.js'],
+    files: ['*.config.{js,ts}', 'eslint.config.js', 'scripts/**/*.mjs'],
     languageOptions: {
       globals: {
         ...globals.node,

index.html

@@ -4,6 +4,12 @@
     <meta charset="UTF-8" />
     <title>Self-hosted PDF Workbench</title>
     <meta name="viewport" content="width=device-width, initial-scale=1" />
+    <link rel="icon" type="image/png" href="/favicon-96x96.png" sizes="96x96" />
+    <link rel="icon" type="image/svg+xml" href="/favicon.svg" />
+    <link rel="shortcut icon" href="/favicon.ico" />
+    <link rel="apple-touch-icon" sizes="180x180" href="/apple-touch-icon.png" />
+    <meta name="apple-mobile-web-app-title" content="PDFTools" />
+    <link rel="manifest" href="/site.webmanifest" />
   </head>
   <body>
     <div id="root"></div>

licenses/core-js-3.49.0-LICENSE.txt

@@ -0,0 +1,24 @@
+core-js 3.49.0 — MIT License
+Source: https://github.com/zloirock/core-js/tree/v3.49.0
+
+Copyright (c) 2013–2025 Denis Pushkarev (zloirock.ru)
+
+Copyright (c) 2025–2026 CoreJS Company (core-js.io)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.

package.json

@@ -1,10 +1,13 @@
 {
   "name": "pdf-tools",
-  "version": "0.3.1",
+  "version": "0.4.4",
   "private": true,
+  "license": "AGPL-3.0-only",
   "type": "module",
   "scripts": {
+    "predev": "npm run manifest:generate",
     "dev": "vite",
+    "prebuild": "npm run manifest:generate",
     "build": "vite build",
     "preview": "vite preview",
     "typecheck": "tsc --noEmit",
@@ -12,10 +15,16 @@
     "format": "prettier --write .",
     "format:check": "prettier --check .",
     "test": "vitest run --environment jsdom",
+    "test:toolbox": "toolbox-check dist",
     "test:watch": "vitest --environment jsdom",
-    "check": "npm run typecheck && npm run lint && npm run test && npm run build"
+    "manifest:generate": "node scripts/generate-toolbox-manifest.mjs",
+    "manifest:check": "node scripts/generate-toolbox-manifest.mjs --check",
+    "release:artifact": "npm run check && node scripts/package-release.mjs",
+    "check": "npm run manifest:check && npm run typecheck && npm run lint && npm run test && npm run build && npm run test:toolbox"
   },
   "dependencies": {
+    "@add-ideas/toolbox-contract": "^0.2.3",
+    "@add-ideas/toolbox-shell-react": "^0.2.3",
     "fflate": "^0.8.3",
     "pdf-lib": "^1.17.1",
     "pdfjs-dist": "^5.7.284",
@@ -23,6 +32,7 @@
     "react-dom": "^19.2.6"
   },
   "devDependencies": {
+    "@add-ideas/toolbox-testkit": "^0.2.3",
     "@eslint/js": "^10.0.1",
     "@testing-library/react": "^16.3.2",
     "@testing-library/user-event": "^14.6.1",
@@ -42,5 +52,13 @@
     "vite": "^8.0.13",
     "vitest": "^4.1.6"
   },
-  "description": "Browser-only, self-hostable PDF workbench for page-level PDF operations."
+  "description": "Browser-only, self-hostable PDF workbench for page-level PDF operations.",
+  "repository": {
+    "type": "git",
+    "url": "git+https://git.add-ideas.de/lotobo/pdf-tools.git"
+  },
+  "homepage": "https://git.add-ideas.de/lotobo/pdf-tools",
+  "bugs": {
+    "url": "https://git.add-ideas.de/lotobo/pdf-tools/issues"
+  }
 }

public/favicon.svg

@@ -0,0 +1,17 @@
+<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 64 64" role="img" aria-label="pdftools favicon" width="64" height="64"><metadata><rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:dc="http://purl.org/dc/elements/1.1/"><rdf:Description><dc:creator>RealFaviconGenerator</dc:creator><dc:source>https://realfavicongenerator.net</dc:source></rdf:Description></rdf:RDF></metadata><defs>
+    <linearGradient id="pdf-bg" x1="10" y1="4" x2="54" y2="60" gradientUnits="userSpaceOnUse">
+      <stop offset="0" stop-color="#ff4b3f"></stop>
+      <stop offset="1" stop-color="#c91424"></stop>
+    </linearGradient>
+    <filter id="soft-shadow" x="-20%" y="-20%" width="140%" height="140%">
+      <feDropShadow dx="0" dy="2" stdDeviation="1.25" flood-color="#7a0b12" flood-opacity="0.28"></feDropShadow>
+    </filter>
+  </defs><rect width="64" height="64" rx="14" fill="url(#pdf-bg)"></rect><g filter="url(#soft-shadow)">
+    <path d="M19 11h22l9 9v31a4 4 0 0 1-4 4H19a4 4 0 0 1-4-4V15a4 4 0 0 1 4-4z" fill="#fff"></path>
+    <path d="M41 11v9h9z" fill="#ffd9d6"></path>
+    <path d="M23 24h19" stroke="#d41627" stroke-width="4" stroke-linecap="round"></path>
+    <path d="M23 34h14" stroke="#d41627" stroke-width="4" stroke-linecap="round" opacity="0.82"></path>
+    <path d="M23 44h19" stroke="#d41627" stroke-width="4" stroke-linecap="round" opacity="0.64"></path>
+  </g><style>@media (prefers-color-scheme: light) { :root { filter: none; } }
+@media (prefers-color-scheme: dark) { :root { filter: none; } }
+</style></svg>

public/site.webmanifest

@@ -0,0 +1,21 @@
+{
+  "name": "PDFTools",
+  "short_name": "PDFTools",
+  "icons": [
+    {
+      "src": "./web-app-manifest-192x192.png",
+      "sizes": "192x192",
+      "type": "image/png",
+      "purpose": "maskable"
+    },
+    {
+      "src": "./web-app-manifest-512x512.png",
+      "sizes": "512x512",
+      "type": "image/png",
+      "purpose": "maskable"
+    }
+  ],
+  "theme_color": "#ffffff",
+  "background_color": "#ffffff",
+  "display": "standalone"
+}

public/toolbox-app.json

@@ -0,0 +1,32 @@
+{
+  "$schema": "https://git.add-ideas.de/lotobo/toolbox-sdk/raw/branch/main/schemas/toolbox-app.v1.schema.json",
+  "schemaVersion": 1,
+  "id": "de.add-ideas.pdf-tools",
+  "name": "PDF Workbench",
+  "description": "Page-level PDF operations performed locally in the browser.",
+  "entry": "./",
+  "icon": "./favicon.svg",
+  "categories": ["documents", "pdf"],
+  "tags": ["merge", "split", "rotate", "reorder"],
+  "integration": {
+    "contextVersion": 1,
+    "launchModes": ["navigate", "new-tab"],
+    "embedding": "unsupported"
+  },
+  "requirements": {
+    "secureContext": true,
+    "workers": true,
+    "indexedDb": true,
+    "crossOriginIsolated": false
+  },
+  "privacy": {
+    "processing": "local",
+    "fileUploads": false,
+    "telemetry": false
+  },
+  "source": {
+    "repository": "https://git.add-ideas.de/lotobo/pdf-tools",
+    "license": "AGPL-3.0-only"
+  },
+  "version": "0.4.4"
+}

scripts/generate-toolbox-manifest.mjs

@@ -0,0 +1,64 @@
+import { readFile, writeFile } from 'node:fs/promises';
+import path from 'node:path';
+import process from 'node:process';
+import { fileURLToPath } from 'node:url';
+import { parseToolboxApp } from '@add-ideas/toolbox-contract';
+import { format } from 'prettier';
+
+const projectRoot = path.resolve(
+  path.dirname(fileURLToPath(import.meta.url)),
+  '..'
+);
+const packageJsonPath = path.join(projectRoot, 'package.json');
+const definitionPath = path.join(
+  projectRoot,
+  'src',
+  'toolboxApp.definition.json'
+);
+const versionSourcePath = path.join(projectRoot, 'src', 'version.ts');
+const manifestPath = path.join(projectRoot, 'public', 'toolbox-app.json');
+
+const [packageJson, definition, versionSource] = await Promise.all([
+  readJson(packageJsonPath),
+  readJson(definitionPath),
+  readFile(versionSourcePath, 'utf8'),
+]);
+
+const sourceVersion = versionSource.match(
+  /APP_VERSION\s*=\s*['"]([^'"]+)['"]/
+)?.[1];
+
+if (!sourceVersion) {
+  throw new Error('Could not read APP_VERSION from src/version.ts.');
+}
+
+if (sourceVersion !== packageJson.version) {
+  throw new Error(
+    `Version mismatch: package.json is ${packageJson.version}, while src/version.ts is ${sourceVersion}.`
+  );
+}
+
+const manifest = {
+  $schema:
+    'https://git.add-ideas.de/lotobo/toolbox-sdk/raw/branch/main/schemas/toolbox-app.v1.schema.json',
+  schemaVersion: 1,
+  ...definition,
+  version: packageJson.version,
+};
+parseToolboxApp(manifest);
+const output = await format(JSON.stringify(manifest), { parser: 'json' });
+
+if (process.argv.includes('--check')) {
+  const existing = await readFile(manifestPath, 'utf8').catch(() => '');
+  if (existing !== output) {
+    throw new Error(
+      'public/toolbox-app.json is out of date. Run npm run manifest:generate.'
+    );
+  }
+} else {
+  await writeFile(manifestPath, output);
+}
+
+async function readJson(filePath) {
+  return JSON.parse(await readFile(filePath, 'utf8'));
+}

scripts/package-release.mjs

@@ -0,0 +1,100 @@
+import { createHash } from 'node:crypto';
+import { access, mkdir, readFile, writeFile } from 'node:fs/promises';
+import path from 'node:path';
+import { fileURLToPath } from 'node:url';
+import {
+  collectDirectoryFiles,
+  createDeterministicZip,
+  createThirdPartyLicenseBundle,
+} from './release-archive.mjs';
+
+const projectRoot = path.resolve(
+  path.dirname(fileURLToPath(import.meta.url)),
+  '..'
+);
+const packageJson = JSON.parse(
+  await readFile(path.join(projectRoot, 'package.json'), 'utf8')
+);
+const releaseDirectory = path.join(projectRoot, 'release');
+const archiveName = `pdf-tools-${packageJson.version}.zip`;
+const archivePath = path.join(releaseDirectory, archiveName);
+const checksumPath = path.join(
+  releaseDirectory,
+  `pdf-tools-${packageJson.version}.sha256`
+);
+const force = process.argv.slice(2).includes('--force');
+const unknownArguments = process.argv
+  .slice(2)
+  .filter((argument) => argument !== '--force');
+if (unknownArguments.length > 0) {
+  throw new Error(`Unknown release argument: ${unknownArguments.join(', ')}`);
+}
+
+await mkdir(releaseDirectory, { recursive: true });
+if (!force) {
+  await assertDoesNotExist(archivePath);
+  await assertDoesNotExist(checksumPath);
+}
+
+const files = await collectDirectoryFiles(path.join(projectRoot, 'dist'));
+
+files['CHANGELOG.md'] = await readFile(path.join(projectRoot, 'CHANGELOG.md'));
+files['SOURCE.md'] = Buffer.from(
+  [
+    '# Corresponding source',
+    '',
+    `The source code corresponding to PDF Tools ${packageJson.version} is available at:`,
+    '',
+    `https://git.add-ideas.de/lotobo/pdf-tools/src/tag/v${packageJson.version}`,
+    '',
+    'Third-party components remain available under the separate terms reproduced in LICENSES/.',
+    '',
+  ].join('\n'),
+  'utf8'
+);
+files['LICENSES/pdf-tools-LICENSE.txt'] = await readFile(
+  path.join(projectRoot, 'LICENSE')
+);
+files['LICENSES/core-js-3.49.0-LICENSE.txt'] = await readFile(
+  path.join(projectRoot, 'licenses', 'core-js-3.49.0-LICENSE.txt')
+);
+files['LICENSES/THIRD-PARTY-LICENSES.txt'] =
+  await createThirdPartyLicenseBundle(projectRoot, [
+    '@add-ideas/toolbox-contract',
+    '@add-ideas/toolbox-shell-react',
+    '@pdf-lib/standard-fonts',
+    '@pdf-lib/upng',
+    'fflate',
+    'pako',
+    'pdf-lib',
+    'pdfjs-dist',
+    'react',
+    'react-dom',
+    'scheduler',
+    'tslib',
+  ]);
+
+const archive = createDeterministicZip(files);
+const checksum = createHash('sha256').update(archive).digest('hex');
+
+const writeFlag = force ? 'w' : 'wx';
+await writeFile(archivePath, archive, { flag: writeFlag });
+await writeFile(checksumPath, `${checksum}  ${archiveName}\n`, {
+  encoding: 'utf8',
+  flag: writeFlag,
+});
+
+console.log(`Created release/${archiveName}`);
+console.log(`SHA-256 ${checksum}`);
+
+async function assertDoesNotExist(outputPath) {
+  try {
+    await access(outputPath);
+  } catch (error) {
+    if (error && typeof error === 'object' && error.code === 'ENOENT') return;
+    throw error;
+  }
+  throw new Error(
+    `${path.relative(projectRoot, outputPath)} already exists; pass --force to replace this exact version.`
+  );
+}

scripts/release-archive.d.ts

@@ -0,0 +1,12 @@
+export function compareCodePoints(left: string, right: string): number;
+export function createDeterministicZip(
+  files: Record<string, Uint8Array>
+): Uint8Array;
+export function collectDirectoryFiles(
+  directory: string,
+  prefix?: string
+): Promise<Record<string, Buffer>>;
+export function createThirdPartyLicenseBundle(
+  projectRoot: string,
+  packageNames: string[]
+): Promise<Buffer>;

scripts/release-archive.mjs

@@ -0,0 +1,123 @@
+import { readFile, readdir } from 'node:fs/promises';
+import path from 'node:path';
+import { zipSync } from 'fflate';
+
+const LICENSE_FILE = /^(?:licen[cs]e|copying|notice)(?:[._-].*)?$/iu;
+
+export function compareCodePoints(left, right) {
+  return left < right ? -1 : left > right ? 1 : 0;
+}
+
+export function createDeterministicZip(files) {
+  const orderedFiles = Object.fromEntries(
+    Object.entries(files).sort(([left], [right]) =>
+      compareCodePoints(left, right)
+    )
+  );
+  return zipSync(orderedFiles, {
+    level: 9,
+    // ZIP stores a wall-clock DOS timestamp. Constructing the epoch in local
+    // time keeps its encoded bytes stable in every process timezone.
+    mtime: new Date(1980, 0, 1, 0, 0, 0),
+  });
+}
+
+export async function collectDirectoryFiles(directory, prefix = '') {
+  const result = {};
+  const entries = await readdir(directory, { withFileTypes: true });
+  entries.sort((left, right) => compareCodePoints(left.name, right.name));
+
+  for (const entry of entries) {
+    const absolutePath = path.join(directory, entry.name);
+    const relativePath = path.posix.join(prefix, entry.name);
+
+    if (entry.isDirectory()) {
+      Object.assign(
+        result,
+        await collectDirectoryFiles(absolutePath, relativePath)
+      );
+    } else if (entry.isFile()) {
+      result[relativePath] = await readFile(absolutePath);
+    } else {
+      throw new Error(
+        `Unsupported filesystem entry in release input: ${relativePath}`
+      );
+    }
+  }
+
+  return result;
+}
+
+export async function createThirdPartyLicenseBundle(projectRoot, packageNames) {
+  const sections = [];
+
+  for (const packageName of [...new Set(packageNames)].sort(
+    compareCodePoints
+  )) {
+    const packageDirectory = path.join(
+      projectRoot,
+      'node_modules',
+      ...packageName.split('/')
+    );
+    const packageJson = JSON.parse(
+      await readFile(path.join(packageDirectory, 'package.json'), 'utf8')
+    );
+    const licenseFiles = await collectLicenseFiles(packageDirectory);
+    if (licenseFiles.length === 0) {
+      throw new Error(`No license text found for ${packageName}.`);
+    }
+
+    const contents = [];
+    for (const licenseFile of licenseFiles) {
+      const text = await readFile(
+        path.join(packageDirectory, ...licenseFile.split('/')),
+        'utf8'
+      );
+      contents.push(
+        `--- ${licenseFile} ---\n${text.replaceAll('\r\n', '\n').trim()}\n`
+      );
+    }
+    sections.push(
+      [
+        `================================================================================`,
+        `${packageJson.name ?? packageName}@${packageJson.version ?? 'unknown'}`,
+        `Declared license: ${String(packageJson.license ?? 'unspecified')}`,
+        `================================================================================`,
+        ...contents,
+      ].join('\n')
+    );
+  }
+
+  return Buffer.from(
+    [
+      'Third-party software license texts bundled with PDF Tools',
+      'Generated deterministically from the installed production packages.',
+      '',
+      ...sections,
+      '',
+    ].join('\n'),
+    'utf8'
+  );
+}
+
+async function collectLicenseFiles(directory, prefix = '') {
+  const matches = [];
+  const entries = await readdir(directory, { withFileTypes: true });
+  entries.sort((left, right) => compareCodePoints(left.name, right.name));
+
+  for (const entry of entries) {
+    if (entry.name === 'node_modules') continue;
+    const relativePath = path.posix.join(prefix, entry.name);
+    const absolutePath = path.join(directory, entry.name);
+    if (entry.isDirectory()) {
+      matches.push(...(await collectLicenseFiles(absolutePath, relativePath)));
+    } else if (entry.isFile() && LICENSE_FILE.test(entry.name)) {
+      matches.push(relativePath);
+    } else if (!entry.isFile()) {
+      throw new Error(
+        `Unsupported filesystem entry in license input: ${relativePath}`
+      );
+    }
+  }
+  return matches;
+}

src/App.tsx

@@ -1,5 +1,5 @@
 import React, { useCallback, useEffect, useState } from 'react';
-import Layout from './components/Layout';
+import { AppShell } from '@add-ideas/toolbox-shell-react';
 import FileLoader from './components/FileLoader';
 import ReorderPanel from './components/ReorderPanel';
 import ActionsPanel from './components/ActionsPanel';
@@ -9,6 +9,7 @@ import ActionDialog, {
   type ActionDialogAction,
 } from './components/ActionDialog';
 import HelpDialog from './components/HelpDialog';
+import MergeQueuePanel from './components/MergeQueuePanel';
 import { PDFDocument } from 'pdf-lib';
 import type {
   StoredWorkspace,
@@ -32,7 +33,7 @@ import {
 import type { PageRef, PdfFile } from './pdf/pdfTypes';
 import {
   loadPdfFromFile,
-  mergePdfFiles,
+  mergePdfFilesAtPosition,
   splitIntoSinglePages,
   exportPages,
 } from './pdf/pdfService';
@@ -42,11 +43,19 @@ import {
   createSplitResultsZip,
   createSplitZipFilename,
 } from './pdf/pdfZipService';
+import { toolboxApp } from './toolboxApp';
 import {
   createSelectionPdfName,
   createSelectionWorkspaceName,
   getSelectedPagesInVisualOrder,
 } from './workspace/workspaceSelection';
+import { useMergeQueue } from './merge/useMergeQueue';
+import {
+  clampMergeInsertAt,
+  createMergedPdfName,
+  defaultMergeInsertPosition,
+} from './merge/mergeQueueHelpers';
+import type { MergeMode } from './merge/mergeTypes';
 
 function isEditableKeyboardTarget(target: EventTarget | null): boolean {
   if (!(target instanceof HTMLElement)) return false;
@@ -80,13 +89,23 @@ const App: React.FC = () => {
 
   const [previewPageId, setPreviewPageId] = useState<string | null>(null);
 
-  const [pendingFile, setPendingFile] = useState<File | null>(null);
+  const [mergeQueueOpen, setMergeQueueOpen] = useState(false);
-  const [showMergeOptions, setShowMergeOptions] = useState(false);
+  const [mergeMode, setMergeMode] = useState<MergeMode>('append');
-  const [mergeMode, setMergeMode] = useState<
-    'overwrite' | 'append' | 'insertAt'
-  >('append');
   const [mergeInsertAt, setMergeInsertAt] = useState<string>('');
 
+  const {
+    items: mergeQueueItems,
+    addFiles: addFilesToMergeQueue,
+    removeItem: removeMergeQueueItem,
+    moveItemUp: moveMergeQueueItemUp,
+    moveItemDown: moveMergeQueueItemDown,
+    clearQueue: clearMergeQueue,
+    readyPdfs: readyMergePdfs,
+    canMerge: canMergeQueue,
+    hasErrors: mergeQueueHasErrors,
+    isLoading: mergeQueueIsLoading,
+  } = useMergeQueue();
+
   const {
     splitDownloads,
     splitZipDownload,
@@ -422,41 +441,63 @@ const App: React.FC = () => {
     }
   };
 
-  const handleFileLoaded = (file: File) => {
+  const queueFilesForMerge = (files: File[]) => {
+    if (files.length === 0) return;
+
+    const queueWasEmpty = mergeQueueItems.length === 0;
+
+    addFilesToMergeQueue(files);
+    setMergeQueueOpen(true);
+
+    if (queueWasEmpty) {
       if (!pdf || pages.length === 0) {
-      void loadFileAsNew(file);
+        setMergeMode('overwrite');
+        setMergeInsertAt('1');
       } else {
-      setPendingFile(file);
-      setShowMergeOptions(true);
         setMergeMode('append');
-      setMergeInsertAt(String(pages.length + 1));
+        setMergeInsertAt(defaultMergeInsertPosition(pages.length));
       }
+    }
+  };
+
+  const handleFilesLoaded = (files: File[]) => {
+    const pdfFiles = files.filter(
+      (file) =>
+        file.type === 'application/pdf' ||
+        file.name.toLowerCase().endsWith('.pdf')
+    );
+
+    if (pdfFiles.length === 0) return;
+
+    if (!pdf && pages.length === 0 && pdfFiles.length === 1) {
+      void loadFileAsNew(pdfFiles[0]);
+      return;
+    }
+
+    queueFilesForMerge(pdfFiles);
   };
 
   const handleMergeCancel = () => {
-    setPendingFile(null);
+    clearMergeQueue();
-    setShowMergeOptions(false);
+    setMergeQueueOpen(false);
   };
 
   const handleMergeConfirm = async () => {
-    if (!pendingFile) return;
+    if (!canMergeQueue || readyMergePdfs.length === 0) return;
-
-    if (!pdf || mergeMode === 'overwrite') {
-      await loadFileAsNew(pendingFile);
-      setPendingFile(null);
-      setShowMergeOptions(false);
-      return;
-    }
 
     setError(null);
     setIsBusy(true);
 
     try {
-      // 1) Materialize the current in-memory workspace (page refs + rotations)
+      let basePdf: PdfFile | null = null;
+      let insertAt = 0;
+
+      if (pdf && pages.length > 0 && mergeMode !== 'overwrite') {
         const currentBlob = await exportPages(pdf, pages);
         const currentArrayBuffer = await currentBlob.arrayBuffer();
         const currentDoc = await PDFDocument.load(currentArrayBuffer);
-      const currentPdf: PdfFile = {
+
+        basePdf = {
           id: pdf.id,
           name: pdf.name,
           doc: currentDoc,
@@ -464,47 +505,47 @@ const App: React.FC = () => {
           pageCount: pages.length,
         };
 
-      // 2) Load the new PDF
+        insertAt =
-      const newPdf = await loadPdfFromFile(pendingFile);
+          mergeMode === 'insertAt'
-
+            ? clampMergeInsertAt(mergeInsertAt, pages.length)
-      // 3) Determine insert position (0-based)
+            : pages.length;
-      let insertAt = pages.length; // default: append at end
-      if (mergeMode === 'insertAt') {
-        const parsed = parseInt(mergeInsertAt, 10);
-        if (Number.isFinite(parsed)) {
-          insertAt = Math.min(Math.max(parsed - 1, 0), pages.length);
-        }
-      } else if (mergeMode === 'append') {
-        insertAt = pages.length;
       }
 
-      // 4) Merge
+      const mergedPdf = await mergePdfFilesAtPosition({
-      const mergedPdf = await mergePdfFiles(currentPdf, newPdf, insertAt);
+        basePdf,
-      const mergedPages = createInitialPageRefs(mergedPdf.pageCount);
+        incomingPdfs: readyMergePdfs,
+        insertAt,
+        name: createMergedPdfName(
+          pdf?.name ?? null,
+          readyMergePdfs.map((item) => item.name),
+          mergeMode
+        ),
+      });
 
-      // 5) Reset state to the merged document
       setPdf(mergedPdf);
       replaceWorkspaceState({
-        pages: mergedPages,
+        pages: createInitialPageRefs(mergedPdf.pageCount),
         selectedPageIds: [],
         lastSelectedVisualIndex: null,
         history: [],
         redoHistory: [],
         dirty: true,
-        message: null,
+        message: `Merged ${readyMergePdfs.length} queued ${
+          readyMergePdfs.length === 1 ? 'PDF' : 'PDFs'
+        } into a new unsaved workspace.`,
       });
       clearGeneratedOutputs();
       clearThumbnailCache();
       setPreviewPageId(null);
       setWorkspaceName(defaultWorkspaceNameFromPdfName(mergedPdf.name));
       setActiveWorkspaceId(null);
+      clearMergeQueue();
+      setMergeQueueOpen(false);
     } catch (e) {
       console.error(e);
-      setError('Failed to merge PDF (see console).');
+      setError('Failed to merge PDF queue (see console).');
     } finally {
       setIsBusy(false);
-      setPendingFile(null);
-      setShowMergeOptions(false);
     }
   };
 
@@ -1099,8 +1140,37 @@ const App: React.FC = () => {
     previewVisualIndex >= 0 && previewVisualIndex < pages.length - 1;
 
   return (
-    <Layout onOpenHelp={() => setHelpOpen(true)}>
+    <AppShell
-      <FileLoader pdf={pdf} onFileLoaded={handleFileLoaded} />
+      app={toolboxApp}
+      className="pdf-toolbox-shell"
+      helpAction={{
+        onClick: () => setHelpOpen(true),
+        title: 'Open help and keyboard shortcuts (F1 or ?)',
+      }}
+    >
+      <FileLoader pdf={pdf} onFilesLoaded={handleFilesLoaded} />
+
+      {mergeQueueOpen && mergeQueueItems.length > 0 && (
+        <MergeQueuePanel
+          items={mergeQueueItems}
+          hasCurrentPdf={hasPdf && pages.length > 0}
+          currentPdfName={pdf?.name ?? null}
+          currentPageCount={pages.length}
+          mergeMode={mergeMode}
+          mergeInsertAt={mergeInsertAt}
+          isBusy={isBusy}
+          canMerge={canMergeQueue}
+          isLoading={mergeQueueIsLoading}
+          hasErrors={mergeQueueHasErrors}
+          onMergeModeChange={setMergeMode}
+          onMergeInsertAtChange={setMergeInsertAt}
+          onMoveUp={moveMergeQueueItemUp}
+          onMoveDown={moveMergeQueueItemDown}
+          onRemove={removeMergeQueueItem}
+          onCancel={handleMergeCancel}
+          onConfirm={handleMergeConfirm}
+        />
+      )}
 
       <WorkspacePanel
         hasPdf={hasPdf}
@@ -1125,105 +1195,6 @@ const App: React.FC = () => {
         onRedo={handleRedo}
       />
 
-      {showMergeOptions && pendingFile && pdf && pages.length > 0 && (
-        <div
-          className="card"
-          style={{ border: '1px solid #bfdbfe', background: '#eff6ff' }}
-        >
-          <h2>Open file: merge or replace?</h2>
-          <p style={{ fontSize: '0.85rem', color: '#374151' }}>
-            You already have <strong>{pdf.name}</strong> with {pages.length}{' '}
-            pages open. What should happen with{' '}
-            <strong>{pendingFile.name}</strong>?
-          </p>
-
-          <div
-            style={{
-              display: 'flex',
-              flexDirection: 'column',
-              gap: '0.5rem',
-              marginTop: '0.5rem',
-              fontSize: '0.9rem',
-            }}
-          >
-            <label
-              style={{ display: 'flex', alignItems: 'center', gap: '0.4rem' }}
-            >
-              <input
-                type="radio"
-                name="mergeMode"
-                value="overwrite"
-                checked={mergeMode === 'overwrite'}
-                onChange={() => setMergeMode('overwrite')}
-              />
-              <span>Replace current document</span>
-            </label>
-
-            <label
-              style={{ display: 'flex', alignItems: 'center', gap: '0.4rem' }}
-            >
-              <input
-                type="radio"
-                name="mergeMode"
-                value="append"
-                checked={mergeMode === 'append'}
-                onChange={() => setMergeMode('append')}
-              />
-              <span>Merge and append pages at the end</span>
-            </label>
-
-            <label
-              style={{ display: 'flex', alignItems: 'center', gap: '0.4rem' }}
-            >
-              <input
-                type="radio"
-                name="mergeMode"
-                value="insertAt"
-                checked={mergeMode === 'insertAt'}
-                onChange={() => setMergeMode('insertAt')}
-              />
-              <span>
-                Merge and insert starting at position{' '}
-                <input
-                  type="number"
-                  min={1}
-                  max={pages.length + 1}
-                  value={mergeInsertAt}
-                  onChange={(e) => setMergeInsertAt(e.target.value)}
-                  style={{
-                    width: '4rem',
-                    padding: '0.15rem 0.3rem',
-                    fontSize: '0.85rem',
-                  }}
-                />{' '}
-                <span style={{ color: '#6b7280' }}>
-                  (1 = before first page, {pages.length + 1} = after last page)
-                </span>
-              </span>
-            </label>
-          </div>
-
-          <div className="button-row" style={{ marginTop: '0.75rem' }}>
-            <button
-              className="secondary"
-              type="button"
-              onClick={handleMergeCancel}
-              disabled={isBusy}
-            >
-              Cancel
-            </button>
-            <button
-              className="primary"
-              type="button"
-              onClick={handleMergeConfirm}
-              disabled={isBusy}
-            >
-              {isBusy ? 'Working…' : 'Continue'}
-            </button>
-          </div>
-        </div>
-      )}
-
       <ReorderPanel
         pages={pages}
         thumbnails={reorderThumbnails}
@@ -1259,7 +1230,11 @@ const App: React.FC = () => {
       {error && (
         <div
           className="card"
-          style={{ border: '1px solid #fecaca', background: '#fef2f2' }}
+          style={{
+            border: '1px solid var(--pdf-danger-border)',
+            background: 'var(--pdf-danger-surface)',
+            color: 'var(--pdf-danger-text)',
+          }}
         >
           <strong>Error:</strong> {error}
         </div>
@@ -1289,7 +1264,7 @@ const App: React.FC = () => {
       </ActionDialog>
 
       <HelpDialog open={helpOpen} onClose={() => setHelpOpen(false)} />
-    </Layout>
+    </AppShell>
   );
 };
 

src/components/ActionDialog.tsx

@@ -21,18 +21,18 @@ const backgroundByVariant: Record<
   NonNullable<ActionDialogAction['variant']>,
   string
 > = {
-  primary: '#2563eb',
+  primary: 'var(--pdf-primary)',
-  secondary: '#e5e7eb',
+  secondary: 'var(--pdf-control)',
-  danger: '#dc2626',
+  danger: 'var(--pdf-danger-text)',
 };
 
 const colorByVariant: Record<
   NonNullable<ActionDialogAction['variant']>,
   string
 > = {
-  primary: 'white',
+  primary: 'var(--pdf-on-primary)',
-  secondary: '#111827',
+  secondary: 'var(--pdf-control-text)',
-  danger: 'white',
+  danger: 'var(--pdf-on-primary)',
 };
 
 const ActionDialog: React.FC<ActionDialogProps> = ({
@@ -75,7 +75,7 @@ const ActionDialog: React.FC<ActionDialogProps> = ({
         position: 'fixed',
         inset: 0,
         zIndex: 70,
-        background: 'rgba(15, 23, 42, 0.55)',
+        background: 'var(--pdf-overlay)',
         display: 'flex',
         alignItems: 'center',
         justifyContent: 'center',
@@ -86,9 +86,10 @@ const ActionDialog: React.FC<ActionDialogProps> = ({
         style={{
           width: '100%',
           maxWidth: '440px',
-          background: 'white',
+          background: 'var(--pdf-surface-raised)',
+          color: 'var(--pdf-text)',
           borderRadius: '0.75rem',
-          boxShadow: '0 20px 40px rgba(15, 23, 42, 0.35)',
+          boxShadow: 'var(--pdf-dialog-shadow)',
           padding: '1rem',
           display: 'flex',
           flexDirection: 'column',
@@ -121,8 +122,8 @@ const ActionDialog: React.FC<ActionDialogProps> = ({
               borderRadius: '999px',
               width: '1.8rem',
               height: '1.8rem',
-              background: '#e5e7eb',
+              background: 'var(--pdf-control)',
-              color: '#111827',
+              color: 'var(--pdf-control-text)',
               cursor: 'pointer',
               fontSize: '1.1rem',
               lineHeight: 1,
@@ -139,7 +140,7 @@ const ActionDialog: React.FC<ActionDialogProps> = ({
         <div
           style={{
             fontSize: '0.9rem',
-            color: '#4b5563',
+            color: 'var(--pdf-muted)',
             lineHeight: 1.45,
           }}
         >
@@ -173,9 +174,11 @@ const ActionDialog: React.FC<ActionDialogProps> = ({
                   borderRadius: '0.5rem',
                   padding: '0.45rem 0.8rem',
                   background: action.disabled
-                    ? '#e5e7eb'
+                    ? 'var(--pdf-control)'
                     : backgroundByVariant[variant],
-                  color: action.disabled ? '#6b7280' : colorByVariant[variant],
+                  color: action.disabled
+                    ? 'var(--pdf-muted-soft)'
+                    : colorByVariant[variant],
                   cursor: action.disabled ? 'default' : 'pointer',
                   fontSize: '0.9rem',
                 }}

src/components/ActionsPanel.tsx

@@ -49,7 +49,7 @@ const ActionsPanel: React.FC<ActionsPanelProps> = ({
   return (
     <div className="card">
       <h2>Tools</h2>
-      <p style={{ fontSize: '0.85rem', color: '#6b7280' }}>
+      <p style={{ fontSize: '0.85rem', color: 'var(--pdf-muted-soft)' }}>
         Use these tools on the current in-memory document (reordered, rotated,
         with deletions). Nothing is uploaded to a server.
       </p>

src/components/FileLoader.tsx

@@ -3,14 +3,14 @@ import type { PdfFile } from '../pdf/pdfTypes';
 
 interface FileLoaderProps {
   pdf: PdfFile | null;
-  onFileLoaded: (file: File) => void;
+  onFilesLoaded: (files: File[]) => void;
 }
 
-const FileLoader: React.FC<FileLoaderProps> = ({ pdf, onFileLoaded }) => {
+const FileLoader: React.FC<FileLoaderProps> = ({ pdf, onFilesLoaded }) => {
   const handleChange = (e: React.ChangeEvent<HTMLInputElement>) => {
-    const file = e.target.files?.[0];
+    const files = Array.from(e.target.files ?? []);
-    if (file) {
+    if (files.length > 0) {
-      onFileLoaded(file);
+      onFilesLoaded(files);
       e.target.value = '';
     }
   };
@@ -18,11 +18,25 @@ const FileLoader: React.FC<FileLoaderProps> = ({ pdf, onFileLoaded }) => {
   return (
     <div className="card">
       <h2>1. Load PDF</h2>
-      <p>Select a PDF file. Processing happens entirely in your browser.</p>
+      <p>
-      <input type="file" accept="application/pdf" onChange={handleChange} />
+        Select one PDF to open it directly, or select several PDFs to place them
+        in the merge queue. Processing happens entirely in your browser.
+      </p>
+      <input
+        type="file"
+        accept="application/pdf"
+        multiple
+        onChange={handleChange}
+      />
 
       {pdf && (
-        <div style={{ marginTop: '0.75rem', fontSize: '0.9rem' }}>
+        <div
+          style={{
+            marginTop: '0.75rem',
+            fontSize: '0.9rem',
+            color: 'var(--pdf-muted)',
+          }}
+        >
           <div>
             <strong>Loaded:</strong> {pdf.name}
           </div>

src/components/HelpDialog.tsx

@@ -34,7 +34,7 @@ const shortcuts = [
 const tutorialSteps = [
   {
     title: '1. Open a PDF or load a workspace',
-    body: 'Start by selecting a local PDF file. If you saved workspaces before, you can restore one from browser storage instead.',
+    body: 'Start by selecting a local PDF file. Select several PDFs to open the merge queue, or restore a saved workspace from browser storage.',
   },
   {
     title: '2. Arrange pages visually',
@@ -50,7 +50,7 @@ const tutorialSteps = [
   },
   {
     title: '5. Split and download results',
-    body: 'Splitting creates individual one-page PDF downloads and a ZIP archive that contains all generated page files.',
+    body: 'Splitting creates individual one-page PDF downloads and a ZIP archive that contains all generated page files. For merging, review the incoming PDF queue, reorder it if needed, then replace, append, or insert the queued PDFs.',
   },
   {
     title: '6. Save your workspace or export a PDF',
@@ -102,7 +102,7 @@ const HelpDialog: React.FC<HelpDialogProps> = ({ open, onClose }) => {
             <h2 id="help-dialog-title">Help & tutorial</h2>
             <p>
               PDF Workbench is a browser-only page workspace. Use it to quickly
-              rearrange, split, merge, rotate, duplicate, and export PDFs
+              rearrange, split, queue-merge, rotate, duplicate, and export PDFs
               without uploading documents to a server.
             </p>
           </div>

src/components/Layout.tsx

@@ -1,47 +0,0 @@
-import React from 'react';
-import { APP_VERSION } from '../version';
-
-interface LayoutProps {
-  children: React.ReactNode;
-  onOpenHelp?: () => void;
-}
-
-const Layout: React.FC<LayoutProps> = ({ children, onOpenHelp }) => {
-  return (
-    <div className="app-root">
-      <header className="app-header">
-        <div className="app-header-content">
-          <div className="app-header-title">
-            <span className="app-logo">📄</span>
-            <div>
-              <h1>PDF Workbench</h1>
-              <small>All in your browser</small>
-            </div>
-          </div>
-
-          <div className="app-header-actions">
-            {onOpenHelp && (
-              <button
-                type="button"
-                className="app-help-button"
-                onClick={onOpenHelp}
-                aria-haspopup="dialog"
-                title="Open help and keyboard shortcuts (F1 or ?)"
-              >
-                Help <span aria-hidden="true">?</span>
-              </button>
-            )}
-
-            <div className="app-version" title={`Version ${APP_VERSION}`}>
-              v{APP_VERSION}
-            </div>
-          </div>
-        </div>
-      </header>
-
-      <main className="app-main">{children}</main>
-    </div>
-  );
-};
-
-export default Layout;

src/components/MergeQueuePanel.tsx

@@ -0,0 +1,235 @@
+import React from 'react';
+import type { MergeQueueItem, MergeMode } from '../merge/mergeTypes';
+
+interface MergeQueuePanelProps {
+  items: MergeQueueItem[];
+  hasCurrentPdf: boolean;
+  currentPdfName: string | null;
+  currentPageCount: number;
+  mergeMode: MergeMode;
+  mergeInsertAt: string;
+  isBusy: boolean;
+  canMerge: boolean;
+  isLoading: boolean;
+  hasErrors: boolean;
+  onMergeModeChange: (mode: MergeMode) => void;
+  onMergeInsertAtChange: (value: string) => void;
+  onMoveUp: (itemId: string) => void;
+  onMoveDown: (itemId: string) => void;
+  onRemove: (itemId: string) => void;
+  onCancel: () => void;
+  onConfirm: () => void;
+}
+
+function formatFileSize(size: number): string {
+  if (size < 1024) return `${size} B`;
+  if (size < 1024 * 1024) return `${(size / 1024).toFixed(1)} KB`;
+  return `${(size / (1024 * 1024)).toFixed(1)} MB`;
+}
+
+const MergeQueuePanel: React.FC<MergeQueuePanelProps> = ({
+  items,
+  hasCurrentPdf,
+  currentPdfName,
+  currentPageCount,
+  mergeMode,
+  mergeInsertAt,
+  isBusy,
+  canMerge,
+  isLoading,
+  hasErrors,
+  onMergeModeChange,
+  onMergeInsertAtChange,
+  onMoveUp,
+  onMoveDown,
+  onRemove,
+  onCancel,
+  onConfirm,
+}) => {
+  const queuedPageCount = items.reduce(
+    (sum, item) => sum + (item.pageCount ?? 0),
+    0
+  );
+
+  return (
+    <div
+      className="card merge-queue-card"
+      style={{
+        border: '1px solid var(--pdf-info-border)',
+        background: 'var(--pdf-info-surface)',
+      }}
+    >
+      <h2>Merge PDF queue</h2>
+      <p style={{ fontSize: '0.85rem', color: 'var(--pdf-info-text)' }}>
+        Add several PDFs, reorder the queue, then merge them into a new unsaved
+        workspace. Processing still happens entirely in your browser.
+      </p>
+
+      {hasCurrentPdf ? (
+        <p style={{ fontSize: '0.85rem', color: 'var(--pdf-info-text)' }}>
+          Current workspace:{' '}
+          <strong>{currentPdfName ?? 'Untitled document'}</strong> with{' '}
+          {currentPageCount} {currentPageCount === 1 ? 'page' : 'pages'}.
+        </p>
+      ) : (
+        <p style={{ fontSize: '0.85rem', color: 'var(--pdf-info-text)' }}>
+          No current workspace is open. The queue will become a new workspace.
+        </p>
+      )}
+
+      <div className="merge-queue-list" aria-label="PDF merge queue">
+        {items.map((item, index) => (
+          <div key={item.id} className="merge-queue-item">
+            <div className="merge-queue-order">#{index + 1}</div>
+            <div className="merge-queue-details">
+              <strong>{item.name}</strong>
+              <span>
+                {formatFileSize(item.size)} ·{' '}
+                {item.status === 'ready' && item.pageCount != null
+                  ? `${item.pageCount} ${item.pageCount === 1 ? 'page' : 'pages'}`
+                  : item.status === 'loading'
+                    ? 'Loading…'
+                    : (item.error ?? 'Error')}
+              </span>
+            </div>
+            <div className="merge-queue-actions">
+              <button
+                type="button"
+                className="secondary"
+                onClick={() => onMoveUp(item.id)}
+                disabled={isBusy || index === 0}
+                title="Move up"
+              >
+                ↑
+              </button>
+              <button
+                type="button"
+                className="secondary"
+                onClick={() => onMoveDown(item.id)}
+                disabled={isBusy || index === items.length - 1}
+                title="Move down"
+              >
+                ↓
+              </button>
+              <button
+                type="button"
+                className="secondary"
+                onClick={() => onRemove(item.id)}
+                disabled={isBusy}
+                title="Remove from queue"
+              >
+                Remove
+              </button>
+            </div>
+          </div>
+        ))}
+      </div>
+
+      <p style={{ fontSize: '0.85rem', color: 'var(--pdf-info-text)' }}>
+        Queue total:{' '}
+        <strong>
+          {items.length} {items.length === 1 ? 'PDF' : 'PDFs'}
+        </strong>
+        {queuedPageCount > 0 && (
+          <>
+            {' '}
+            · {queuedPageCount} {queuedPageCount === 1 ? 'page' : 'pages'}
+          </>
+        )}
+      </p>
+
+      <div className="merge-mode-group">
+        <label>
+          <input
+            type="radio"
+            name="mergeMode"
+            value="overwrite"
+            checked={mergeMode === 'overwrite'}
+            onChange={() => onMergeModeChange('overwrite')}
+            disabled={isBusy}
+          />
+          <span>
+            {hasCurrentPdf ? 'Replace current document' : 'Create from queue'}
+          </span>
+        </label>
+
+        <label>
+          <input
+            type="radio"
+            name="mergeMode"
+            value="append"
+            checked={mergeMode === 'append'}
+            onChange={() => onMergeModeChange('append')}
+            disabled={isBusy || !hasCurrentPdf}
+          />
+          <span>Append queue after current workspace</span>
+        </label>
+
+        <label>
+          <input
+            type="radio"
+            name="mergeMode"
+            value="insertAt"
+            checked={mergeMode === 'insertAt'}
+            onChange={() => onMergeModeChange('insertAt')}
+            disabled={isBusy || !hasCurrentPdf}
+          />
+          <span>
+            Insert queue starting at position{' '}
+            <input
+              type="number"
+              min={1}
+              max={currentPageCount + 1}
+              value={mergeInsertAt}
+              onChange={(e) => onMergeInsertAtChange(e.target.value)}
+              disabled={isBusy || !hasCurrentPdf || mergeMode !== 'insertAt'}
+              style={{
+                width: '4rem',
+                padding: '0.15rem 0.3rem',
+                fontSize: '0.85rem',
+              }}
+            />{' '}
+            <span style={{ color: 'var(--pdf-muted-soft)' }}>
+              (1 = before first page, {currentPageCount + 1} = after last page)
+            </span>
+          </span>
+        </label>
+      </div>
+
+      {mergeMode === 'overwrite' && hasCurrentPdf && (
+        <p className="merge-warning">
+          Replace mode discards the current in-memory workspace after the merge.
+          Save it first if you want to keep the current state separately.
+        </p>
+      )}
+
+      {hasErrors && (
+        <p className="merge-warning">
+          One or more queued files could not be loaded. Remove failed items
+          before merging.
+        </p>
+      )}
+
+      <div className="button-row" style={{ marginTop: '0.75rem' }}>
+        <button
+          className="secondary"
+          type="button"
+          onClick={onCancel}
+          disabled={isBusy}
+        >
+          Cancel
+        </button>
+        <button
+          className="primary"
+          type="button"
+          onClick={onConfirm}
+          disabled={isBusy || isLoading || !canMerge || hasErrors}
+        >
+          {isBusy ? 'Working…' : isLoading ? 'Loading PDFs…' : 'Merge queue'}
+        </button>
+      </div>
+    </div>
+  );
+};
+
+export default MergeQueuePanel;

src/components/PagePreviewModal.tsx

@@ -1,11 +1,6 @@
 import React, { useEffect, useRef } from 'react';
 import type { PdfFile } from '../pdf/pdfTypes';
-import * as pdfjsLib from 'pdfjs-dist';
+import { pdfjsLib } from '../pdf/pdfJs';
-import pdfjsWorker from 'pdfjs-dist/build/pdf.worker?worker&url';
-
-// pdf.js worker setup
-// eslint-disable-next-line @typescript-eslint/no-explicit-any
-(pdfjsLib as any).GlobalWorkerOptions.workerSrc = pdfjsWorker;
 
 interface PagePreviewModalProps {
   isOpen: boolean;

src/components/PageWorkspace/CopyPagesDialog.tsx

@@ -48,7 +48,7 @@ const CopyPagesDialog: React.FC<CopyPagesDialogProps> = ({
         position: 'fixed',
         inset: 0,
         zIndex: 60,
-        background: 'rgba(15, 23, 42, 0.55)',
+        background: 'var(--pdf-overlay)',
         display: 'flex',
         alignItems: 'center',
         justifyContent: 'center',
@@ -60,9 +60,10 @@ const CopyPagesDialog: React.FC<CopyPagesDialogProps> = ({
         style={{
           width: '100%',
           maxWidth: '420px',
-          background: 'white',
+          background: 'var(--pdf-surface-raised)',
+          color: 'var(--pdf-text)',
           borderRadius: '0.75rem',
-          boxShadow: '0 20px 40px rgba(15, 23, 42, 0.35)',
+          boxShadow: 'var(--pdf-dialog-shadow)',
           padding: '1rem',
           display: 'flex',
           flexDirection: 'column',
@@ -95,8 +96,8 @@ const CopyPagesDialog: React.FC<CopyPagesDialogProps> = ({
               borderRadius: '999px',
               width: '1.8rem',
               height: '1.8rem',
-              background: '#e5e7eb',
+              background: 'var(--pdf-control)',
-              color: '#111827',
+              color: 'var(--pdf-control-text)',
               cursor: 'pointer',
               fontSize: '1.1rem',
               lineHeight: 1,
@@ -114,7 +115,7 @@ const CopyPagesDialog: React.FC<CopyPagesDialogProps> = ({
           style={{
             margin: 0,
             fontSize: '0.9rem',
-            color: '#4b5563',
+            color: 'var(--pdf-muted)',
           }}
         >
           Copy{' '}
@@ -145,7 +146,7 @@ const CopyPagesDialog: React.FC<CopyPagesDialogProps> = ({
             style={{
               padding: '0.45rem 0.55rem',
               borderRadius: '0.5rem',
-              border: '1px solid #d1d5db',
+              border: '1px solid var(--pdf-border-strong)',
               fontSize: '0.95rem',
             }}
           />
@@ -154,7 +155,7 @@ const CopyPagesDialog: React.FC<CopyPagesDialogProps> = ({
         <div
           style={{
             fontSize: '0.8rem',
-            color: '#6b7280',
+            color: 'var(--pdf-muted-soft)',
             lineHeight: 1.4,
           }}
         >
@@ -166,9 +167,9 @@ const CopyPagesDialog: React.FC<CopyPagesDialogProps> = ({
           <div
             style={{
               borderRadius: '0.5rem',
-              background: '#fef2f2',
+              background: 'var(--pdf-danger-surface)',
-              border: '1px solid #fecaca',
+              border: '1px solid var(--pdf-danger-border)',
-              color: '#b91c1c',
+              color: 'var(--pdf-danger-text)',
               padding: '0.5rem',
               fontSize: '0.85rem',
             }}
@@ -192,8 +193,8 @@ const CopyPagesDialog: React.FC<CopyPagesDialogProps> = ({
               border: 'none',
               borderRadius: '0.5rem',
               padding: '0.45rem 0.8rem',
-              background: '#e5e7eb',
+              background: 'var(--pdf-control)',
-              color: '#111827',
+              color: 'var(--pdf-control-text)',
               cursor: 'pointer',
               fontSize: '0.9rem',
             }}
@@ -207,8 +208,8 @@ const CopyPagesDialog: React.FC<CopyPagesDialogProps> = ({
               border: 'none',
               borderRadius: '0.5rem',
               padding: '0.45rem 0.8rem',
-              background: '#16a34a',
+              background: 'var(--pdf-success-text)',
-              color: 'white',
+              color: 'var(--pdf-on-primary)',
               cursor: 'pointer',
               fontSize: '0.9rem',
             }}

src/components/PageWorkspace/PageCard.tsx

@@ -53,11 +53,11 @@ const PageCard: React.FC<PageCardProps> = ({
 }) => {
   const background = isDraggingCard
     ? isCopyDragging
-      ? '#dcfce7'
+      ? 'var(--pdf-success-soft)'
-      : '#dbeafe'
+      : 'var(--pdf-info-surface)'
     : selected
-      ? '#eff6ff'
+      ? 'var(--pdf-info-surface)'
-      : '#f9fafb';
+      : 'var(--pdf-surface-soft)';
 
   return (
     <div
@@ -71,7 +71,7 @@ const PageCard: React.FC<PageCardProps> = ({
         width: '162px',
         padding: '0.4rem',
         borderRadius: '0.5rem',
-        border: '1px solid #e5e7eb',
+        border: '1px solid var(--pdf-border)',
         background,
         display: 'flex',
         flexDirection: 'column',
@@ -91,9 +91,11 @@ const PageCard: React.FC<PageCardProps> = ({
           width: '20px',
           height: '20px',
           borderRadius: '0.4rem',
-          border: '1px solid #9ca3af',
+          border: '1px solid var(--pdf-border-strong)',
-          background: selected ? '#2563eb' : 'rgba(255,255,255,0.9)',
+          background: selected
-          color: selected ? 'white' : 'transparent',
+            ? 'var(--pdf-primary)'
+            : 'color-mix(in srgb, var(--pdf-surface) 92%, transparent)',
+          color: selected ? 'var(--pdf-on-primary)' : 'transparent',
           fontSize: '0.8rem',
           display: 'flex',
           alignItems: 'center',
@@ -131,8 +133,8 @@ const PageCard: React.FC<PageCardProps> = ({
               height: 'auto',
               objectFit: 'contain',
               borderRadius: '0.25rem',
-              border: '1px solid #e5e7eb',
+              border: '1px solid var(--pdf-paper-border)',
-              background: 'white',
+              background: 'var(--pdf-paper)',
             }}
           />
         ) : (
@@ -141,8 +143,8 @@ const PageCard: React.FC<PageCardProps> = ({
               width: '60px',
               height: '80px',
               borderRadius: '0.25rem',
-              border: '1px dashed #d1d5db',
+              border: '1px dashed var(--pdf-paper-border)',
-              background: '#f3f4f6',
+              background: 'var(--pdf-paper-placeholder)',
             }}
           />
         )}
@@ -151,7 +153,7 @@ const PageCard: React.FC<PageCardProps> = ({
       <span style={{ fontSize: '0.8rem' }}>
         Page {page.sourcePageIndex + 1}
       </span>
-      <span style={{ fontSize: '0.7rem', color: '#6b7280' }}>
+      <span style={{ fontSize: '0.7rem', color: 'var(--pdf-muted-soft)' }}>
         Pos {visualIndex + 1} · Rot {page.rotation}°
       </span>
 
@@ -170,7 +172,8 @@ const PageCard: React.FC<PageCardProps> = ({
           }}
           style={{
             ...pageActionButtonStyle,
-            background: '#e5e7eb',
+            background: 'var(--pdf-control)',
+            color: 'var(--pdf-control-text)',
           }}
         >
           ↻ 90°
@@ -184,7 +187,8 @@ const PageCard: React.FC<PageCardProps> = ({
           }}
           style={{
             ...pageActionButtonStyle,
-            background: '#e5e7eb',
+            background: 'var(--pdf-control)',
+            color: 'var(--pdf-control-text)',
           }}
         >
           ↺ 90°
@@ -198,8 +202,8 @@ const PageCard: React.FC<PageCardProps> = ({
           }}
           style={{
             ...pageActionButtonStyle,
-            background: '#fecaca',
+            background: 'var(--pdf-danger-soft)',
-            color: '#b91c1c',
+            color: 'var(--pdf-danger-text)',
           }}
           title="Remove this page from the exported PDF"
         >

src/components/PageWorkspace/PageSelectionToolbar.tsx

@@ -53,8 +53,8 @@ const PageSelectionToolbar: React.FC<PageSelectionToolbarProps> = ({
             disabled={!hasSelection}
             style={{
               ...pillButtonStyle,
-              background: '#dcfce7',
+              background: 'var(--pdf-success-soft)',
-              color: '#166534',
+              color: 'var(--pdf-success-text)',
               cursor: 'pointer',
             }}
             title="Copy selected pages to another position"
@@ -69,8 +69,8 @@ const PageSelectionToolbar: React.FC<PageSelectionToolbarProps> = ({
             onClick={onDeleteSelected}
             style={{
               ...pillButtonStyle,
-              background: '#fee2e2',
+              background: 'var(--pdf-danger-soft)',
-              color: '#b91c1c',
+              color: 'var(--pdf-danger-text)',
               cursor: 'pointer',
             }}
           >
@@ -83,8 +83,8 @@ const PageSelectionToolbar: React.FC<PageSelectionToolbarProps> = ({
           onClick={onSelectAll}
           style={{
             ...pillButtonStyle,
-            background: '#8dcd8d',
+            background: 'var(--pdf-success-border)',
-            color: '#111827',
+            color: 'var(--pdf-control-text)',
             cursor: 'pointer',
           }}
         >
@@ -97,8 +97,10 @@ const PageSelectionToolbar: React.FC<PageSelectionToolbarProps> = ({
           disabled={!hasSelection}
           style={{
             ...pillButtonStyle,
-            background: '#e5e7eb',
+            background: 'var(--pdf-control)',
-            color: hasSelection ? '#111827' : '#6b7280',
+            color: hasSelection
+              ? 'var(--pdf-control-text)'
+              : 'var(--pdf-muted-soft)',
             cursor: hasSelection ? 'pointer' : 'default',
           }}
         >

src/components/ReorderPanel.tsx

@@ -279,13 +279,15 @@ const ReorderPanel: React.FC<ReorderPanelProps> = ({
     draggingPage != null &&
     selectedPageIds.length > 0 &&
     selectedPageIds.includes(draggingPage.id);
-  const dropIndicatorColor = isCopyDragging ? '#16a34a' : '#2563eb';
+  const dropIndicatorColor = isCopyDragging
+    ? 'var(--pdf-success-text)'
+    : 'var(--pdf-primary)';
 
   return (
     <>
       <div className="card">
         <h2>Pages</h2>
-        <p style={{ fontSize: '0.85rem', color: '#6b7280' }}>
+        <p style={{ fontSize: '0.85rem', color: 'var(--pdf-muted-soft)' }}>
           Tap/click a page to preview it. Use the checkbox to select pages
           (Shift for ranges). Drag to reorder; dragging a selected page moves
           the whole selection. Hold Ctrl/⌘ while dropping to copy instead of

src/components/WorkspacePanel.tsx

@@ -54,7 +54,7 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
     <div className="card">
       <h2>Workspace</h2>
 
-      <p style={{ fontSize: '0.85rem', color: '#6b7280' }}>
+      <p style={{ fontSize: '0.85rem', color: 'var(--pdf-muted-soft)' }}>
         Save named workspaces in this browser. PDF binaries are stored in
         IndexedDB; nothing is uploaded.
       </p>
@@ -78,7 +78,7 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
             minWidth: 0,
             padding: '0.45rem 0.55rem',
             borderRadius: '0.5rem',
-            border: '1px solid #d1d5db',
+            border: '1px solid var(--pdf-border-strong)',
             fontSize: '0.9rem',
           }}
         />
@@ -140,7 +140,7 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
           style={{
             marginTop: '0.5rem',
             fontSize: '0.8rem',
-            color: '#92400e',
+            color: 'var(--pdf-warning-text)',
           }}
         >
           Unsaved workspace changes.
@@ -152,7 +152,7 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
           style={{
             marginTop: '0.5rem',
             fontSize: '0.85rem',
-            color: '#166534',
+            color: 'var(--pdf-success-text)',
           }}
         >
           {workspaceMessage}
@@ -178,10 +178,12 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
                 <div
                   key={workspace.id}
                   style={{
-                    border: '1px solid #e5e7eb',
+                    border: '1px solid var(--pdf-border)',
                     borderRadius: '0.5rem',
                     padding: '0.5rem',
-                    background: active ? '#eff6ff' : '#f9fafb',
+                    background: active
+                      ? 'var(--pdf-info-surface)'
+                      : 'var(--pdf-surface-soft)',
                     display: 'flex',
                     justifyContent: 'space-between',
                     gap: '0.75rem',
@@ -193,11 +195,19 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
                     <div style={{ fontSize: '0.9rem' }}>
                       <strong>{workspace.name}</strong>
                       {active && (
-                        <span style={{ color: '#2563eb' }}> · active</span>
+                        <span style={{ color: 'var(--pdf-primary)' }}>
+                          {' '}
+                          · active
+                        </span>
                       )}
                     </div>
 
-                    <div style={{ fontSize: '0.75rem', color: '#6b7280' }}>
+                    <div
+                      style={{
+                        fontSize: '0.75rem',
+                        color: 'var(--pdf-muted-soft)',
+                      }}
+                    >
                       {workspace.pdfName} · source pages:{' '}
                       {workspace.sourcePageCount} · workspace pages:{' '}
                       {workspace.workspacePageCount} · undo:{' '}
@@ -228,8 +238,8 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
                       disabled={isBusy}
                       onClick={() => onDeleteWorkspace(workspace.id)}
                       style={{
-                        background: '#fee2e2',
+                        background: 'var(--pdf-danger-soft)',
-                        color: '#991b1b',
+                        color: 'var(--pdf-danger-text)',
                       }}
                     >
                       Delete
@@ -261,8 +271,8 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
                 key={entry.id}
                 style={{
                   fontSize: '0.8rem',
-                  color: '#374151',
+                  color: 'var(--pdf-muted)',
-                  borderLeft: '3px solid #2563eb',
+                  borderLeft: '3px solid var(--pdf-primary)',
                   paddingLeft: '0.45rem',
                   paddingTop: '0.2rem',
                   paddingBottom: '0.2rem',
@@ -272,7 +282,7 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
                   Undo {history.length - index}. {entry.label}
                 </strong>
                 <br />
-                <span style={{ color: '#6b7280' }}>
+                <span style={{ color: 'var(--pdf-muted-soft)' }}>
                   {new Date(entry.timestamp).toLocaleString()}
                 </span>
               </div>
@@ -282,12 +292,12 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
               style={{
                 margin: '0.25rem 0',
                 borderRadius: '999px',
-                background: '#ecfdf5',
+                background: 'var(--pdf-success-surface)',
-                color: '#166534',
+                color: 'var(--pdf-success-text)',
                 fontSize: '0.8rem',
                 fontWeight: 600,
                 alignSelf: 'flex-start',
-                border: '2px solid #166534',
+                border: '2px solid var(--pdf-success-text)',
                 width: '100%',
               }}
             ></div>
@@ -300,8 +310,8 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
                   key={entry.id}
                   style={{
                     fontSize: '0.8rem',
-                    color: '#9ca3af',
+                    color: 'var(--pdf-muted-faint)',
-                    borderLeft: '3px solid #d1d5db',
+                    borderLeft: '3px solid var(--pdf-border-strong)',
                     paddingLeft: '0.45rem',
                     paddingTop: '0.2rem',
                     paddingBottom: '0.2rem',
@@ -312,7 +322,7 @@ const WorkspacePanel: React.FC<WorkspacePanelProps> = ({
                     Redo {index + 1}. {entry.label}
                   </strong>
                   <br />
-                  <span style={{ color: '#9ca3af' }}>
+                  <span style={{ color: 'var(--pdf-muted-faint)' }}>
                     {new Date(entry.timestamp).toLocaleString()}
                   </span>
                 </div>

src/main.tsx

@@ -1,6 +1,7 @@
 import React from 'react';
 import ReactDOM from 'react-dom/client';
 import App from './App';
+import '@add-ideas/toolbox-shell-react/styles.css';
 import './styles.css';
 
 ReactDOM.createRoot(document.getElementById('root') as HTMLElement).render(

src/merge/mergeQueueHelpers.test.ts

@@ -0,0 +1,82 @@
+import { describe, expect, it } from 'vitest';
+import type { MergeQueueItem } from './mergeTypes';
+import {
+  canMergeQueue,
+  clampMergeInsertAt,
+  createMergedPdfName,
+  getReadyMergeQueuePdfs,
+  moveMergeQueueItem,
+} from './mergeQueueHelpers';
+
+function makeItem(
+  id: string,
+  status: MergeQueueItem['status']
+): MergeQueueItem {
+  return {
+    id,
+    file: new File(['x'], `${id}.pdf`, { type: 'application/pdf' }),
+    name: `${id}.pdf`,
+    size: 1,
+    pageCount: status === 'ready' ? 1 : null,
+    pdf:
+      status === 'ready'
+        ? {
+            id: `pdf-${id}`,
+            name: `${id}.pdf`,
+            // The helper tests never dereference the PDFDocument.
+            doc: {} as never,
+            pageCount: 1,
+            arrayBuffer: new ArrayBuffer(0),
+          }
+        : null,
+    status,
+  };
+}
+
+describe('merge queue helpers', () => {
+  it('moves queued items up and down without mutating the original array', () => {
+    const items = [
+      makeItem('a', 'ready'),
+      makeItem('b', 'ready'),
+      makeItem('c', 'ready'),
+    ];
+
+    expect(moveMergeQueueItem(items, 'b', 'up').map((item) => item.id)).toEqual(
+      ['b', 'a', 'c']
+    );
+    expect(
+      moveMergeQueueItem(items, 'b', 'down').map((item) => item.id)
+    ).toEqual(['a', 'c', 'b']);
+    expect(items.map((item) => item.id)).toEqual(['a', 'b', 'c']);
+  });
+
+  it('only allows merging when every queued item is ready', () => {
+    const readyItems = [makeItem('a', 'ready'), makeItem('b', 'ready')];
+    const mixedItems = [makeItem('a', 'ready'), makeItem('b', 'loading')];
+
+    expect(canMergeQueue(readyItems)).toBe(true);
+    expect(getReadyMergeQueuePdfs(readyItems)).toHaveLength(2);
+    expect(canMergeQueue(mixedItems)).toBe(false);
+    expect(canMergeQueue([])).toBe(false);
+  });
+
+  it('clamps one-based merge positions to zero-based insert slots', () => {
+    expect(clampMergeInsertAt('1', 10)).toBe(0);
+    expect(clampMergeInsertAt('5', 10)).toBe(4);
+    expect(clampMergeInsertAt('99', 10)).toBe(10);
+    expect(clampMergeInsertAt('-10', 10)).toBe(0);
+    expect(clampMergeInsertAt('not-a-number', 10)).toBe(10);
+  });
+
+  it('creates readable merged PDF filenames', () => {
+    expect(createMergedPdfName('base.pdf', ['a.pdf', 'b.pdf'], 'append')).toBe(
+      'base_plus_2_pdfs.pdf'
+    );
+    expect(createMergedPdfName('base.pdf', ['a.pdf'], 'overwrite')).toBe(
+      'a_merged.pdf'
+    );
+    expect(createMergedPdfName(null, ['a.pdf', 'b.pdf'], 'overwrite')).toBe(
+      'merged_2_pdfs.pdf'
+    );
+  });
+});

src/merge/mergeQueueHelpers.ts

@@ -0,0 +1,86 @@
+import type { PdfFile } from '../pdf/pdfTypes';
+import type { MergeMode, MergeQueueItem } from './mergeTypes';
+
+export function createMergeQueueItemId(): string {
+  return `merge_${Math.random().toString(36).slice(2)}`;
+}
+
+export function moveMergeQueueItem(
+  items: MergeQueueItem[],
+  itemId: string,
+  direction: 'up' | 'down'
+): MergeQueueItem[] {
+  const index = items.findIndex((item) => item.id === itemId);
+  if (index < 0) return items;
+
+  const targetIndex = direction === 'up' ? index - 1 : index + 1;
+  if (targetIndex < 0 || targetIndex >= items.length) return items;
+
+  const next = [...items];
+  const [item] = next.splice(index, 1);
+  next.splice(targetIndex, 0, item);
+  return next;
+}
+
+export function getReadyMergeQueuePdfs(items: MergeQueueItem[]): PdfFile[] {
+  return items
+    .filter((item) => item.status === 'ready' && item.pdf)
+    .map((item) => item.pdf as PdfFile);
+}
+
+export function canMergeQueue(items: MergeQueueItem[]): boolean {
+  return (
+    items.length > 0 &&
+    items.every((item) => item.status === 'ready' && item.pdf !== null)
+  );
+}
+
+export function hasMergeQueueErrors(items: MergeQueueItem[]): boolean {
+  return items.some((item) => item.status === 'error');
+}
+
+export function isMergeQueueLoading(items: MergeQueueItem[]): boolean {
+  return items.some((item) => item.status === 'loading');
+}
+
+export function clampMergeInsertAt(value: string, pageCount: number): number {
+  const parsed = Number.parseInt(value, 10);
+  if (!Number.isFinite(parsed)) return pageCount;
+
+  return Math.min(Math.max(parsed - 1, 0), pageCount);
+}
+
+export function defaultMergeInsertPosition(pageCount: number): string {
+  return String(pageCount + 1);
+}
+
+export function createMergedPdfName(
+  currentPdfName: string | null,
+  incomingPdfNames: string[],
+  mode: MergeMode
+): string {
+  const incomingBaseNames = incomingPdfNames.map(stripPdfExtension);
+
+  if (incomingBaseNames.length === 0) {
+    return currentPdfName ?? 'merged.pdf';
+  }
+
+  if (
+    incomingBaseNames.length === 1 &&
+    (!currentPdfName || mode === 'overwrite')
+  ) {
+    return `${incomingBaseNames[0]}_merged.pdf`;
+  }
+
+  if (currentPdfName && mode !== 'overwrite') {
+    const currentBaseName = stripPdfExtension(currentPdfName);
+    return `${currentBaseName}_plus_${incomingBaseNames.length}_pdfs.pdf`;
+  }
+
+  return `merged_${incomingBaseNames.length}_pdfs.pdf`;
+}
+
+function stripPdfExtension(filename: string): string {
+  const base = filename.replace(/\.pdf$/i, '').trim();
+  return base || 'document';
+}

src/merge/mergeTypes.ts

@@ -0,0 +1,16 @@
+import type { PdfFile } from '../pdf/pdfTypes';
+
+export type MergeMode = 'overwrite' | 'append' | 'insertAt';
+
+export type MergeQueueItemStatus = 'loading' | 'ready' | 'error';
+
+export interface MergeQueueItem {
+  id: string;
+  file: File;
+  name: string;
+  size: number;
+  pageCount: number | null;
+  pdf: PdfFile | null;
+  status: MergeQueueItemStatus;
+  error?: string;
+}

src/merge/useMergeQueue.ts

@@ -0,0 +1,102 @@
+import { useCallback, useState } from 'react';
+import { loadPdfFromFile } from '../pdf/pdfService';
+import {
+  canMergeQueue,
+  createMergeQueueItemId,
+  getReadyMergeQueuePdfs,
+  hasMergeQueueErrors,
+  isMergeQueueLoading,
+  moveMergeQueueItem,
+} from './mergeQueueHelpers';
+import type { MergeQueueItem } from './mergeTypes';
+
+export function useMergeQueue() {
+  const [items, setItems] = useState<MergeQueueItem[]>([]);
+
+  const addFiles = useCallback((files: File[]) => {
+    const pdfFiles = files.filter(
+      (file) =>
+        file.type === 'application/pdf' ||
+        file.name.toLowerCase().endsWith('.pdf')
+    );
+
+    if (pdfFiles.length === 0) return;
+
+    const queuedItems: MergeQueueItem[] = pdfFiles.map((file) => ({
+      id: createMergeQueueItemId(),
+      file,
+      name: file.name,
+      size: file.size,
+      pageCount: null,
+      pdf: null,
+      status: 'loading',
+    }));
+
+    setItems((current) => [...current, ...queuedItems]);
+
+    queuedItems.forEach((item) => {
+      void (async () => {
+        try {
+          const loadedPdf = await loadPdfFromFile(item.file);
+
+          setItems((current) =>
+            current.map((currentItem) =>
+              currentItem.id === item.id
+                ? {
+                    ...currentItem,
+                    pdf: loadedPdf,
+                    pageCount: loadedPdf.pageCount,
+                    status: 'ready',
+                    error: undefined,
+                  }
+                : currentItem
+            )
+          );
+        } catch (error) {
+          console.error(error);
+
+          setItems((current) =>
+            current.map((currentItem) =>
+              currentItem.id === item.id
+                ? {
+                    ...currentItem,
+                    status: 'error',
+                    error: 'Could not load this PDF.',
+                  }
+                : currentItem
+            )
+          );
+        }
+      })();
+    });
+  }, []);
+
+  const removeItem = useCallback((itemId: string) => {
+    setItems((current) => current.filter((item) => item.id !== itemId));
+  }, []);
+
+  const moveItemUp = useCallback((itemId: string) => {
+    setItems((current) => moveMergeQueueItem(current, itemId, 'up'));
+  }, []);
+
+  const moveItemDown = useCallback((itemId: string) => {
+    setItems((current) => moveMergeQueueItem(current, itemId, 'down'));
+  }, []);
+
+  const clearQueue = useCallback(() => {
+    setItems([]);
+  }, []);
+
+  return {
+    items,
+    addFiles,
+    removeItem,
+    moveItemUp,
+    moveItemDown,
+    clearQueue,
+    readyPdfs: getReadyMergeQueuePdfs(items),
+    canMerge: canMergeQueue(items),
+    hasErrors: hasMergeQueueErrors(items),
+    isLoading: isMergeQueueLoading(items),
+  };
+}

src/pdf/pdfJs.ts

@@ -0,0 +1,9 @@
+import './uint8ArrayToHexPolyfill';
+import * as pdfjsLib from 'pdfjs-dist/legacy/build/pdf.mjs';
+import pdfjsWorker from './pdfjsWorker?worker&url';
+
+// pdf.js worker setup for Vite.
+// eslint-disable-next-line @typescript-eslint/no-explicit-any
+(pdfjsLib as any).GlobalWorkerOptions.workerSrc = pdfjsWorker;
+
+export { pdfjsLib };

src/pdf/pdfMergeService.test.ts

@@ -0,0 +1,57 @@
+import { PDFDocument } from 'pdf-lib';
+import { describe, expect, it } from 'vitest';
+import type { PdfFile } from './pdfTypes';
+import { mergePdfFilesAtPosition } from './pdfService';
+
+async function makePdf(name: string, pageCount: number): Promise<PdfFile> {
+  const doc = await PDFDocument.create();
+  for (let i = 0; i < pageCount; i += 1) {
+    doc.addPage([100, 100]);
+  }
+
+  const bytes = await doc.save();
+  const arrayBuffer = new ArrayBuffer(bytes.byteLength);
+  new Uint8Array(arrayBuffer).set(bytes);
+
+  return {
+    id: name,
+    name,
+    doc,
+    pageCount,
+    arrayBuffer,
+  };
+}
+
+describe('mergePdfFilesAtPosition', () => {
+  it('merges a queue without a current base PDF', async () => {
+    const first = await makePdf('first.pdf', 1);
+    const second = await makePdf('second.pdf', 2);
+
+    const merged = await mergePdfFilesAtPosition({
+      basePdf: null,
+      incomingPdfs: [first, second],
+      insertAt: 0,
+      name: 'merged.pdf',
+    });
+
+    expect(merged.name).toBe('merged.pdf');
+    expect(merged.pageCount).toBe(3);
+    expect(merged.doc.getPageCount()).toBe(3);
+  });
+
+  it('inserts queued PDFs into a current base PDF at the requested slot', async () => {
+    const base = await makePdf('base.pdf', 3);
+    const incoming = await makePdf('incoming.pdf', 2);
+
+    const merged = await mergePdfFilesAtPosition({
+      basePdf: base,
+      incomingPdfs: [incoming],
+      insertAt: 1,
+      name: 'base_plus_incoming.pdf',
+    });
+
+    expect(merged.name).toBe('base_plus_incoming.pdf');
+    expect(merged.pageCount).toBe(5);
+    expect(merged.doc.getPageCount()).toBe(5);
+  });
+});

src/pdf/pdfService.ts

@@ -77,6 +77,76 @@ export async function mergePdfFiles(
   };
 }
 
+interface MergePdfFilesAtPositionOptions {
+  basePdf: PdfFile | null;
+  incomingPdfs: PdfFile[];
+  insertAt: number;
+  name: string;
+}
+
+export async function mergePdfFilesAtPosition({
+  basePdf,
+  incomingPdfs,
+  insertAt,
+  name,
+}: MergePdfFilesAtPositionOptions): Promise<PdfFile> {
+  if (!basePdf && incomingPdfs.length === 0) {
+    throw new Error('At least one PDF is required for merging');
+  }
+
+  const mergedDoc = await PDFDocument.create();
+
+  const addAllPages = async (sourcePdf: PdfFile) => {
+    const sourceDoc =
+      sourcePdf.doc ?? (await PDFDocument.load(sourcePdf.arrayBuffer));
+    const pageCount = sourceDoc.getPageCount();
+    const pages = await mergedDoc.copyPages(
+      sourceDoc,
+      Array.from({ length: pageCount }, (_, i) => i)
+    );
+    pages.forEach((page) => mergedDoc.addPage(page));
+  };
+
+  if (!basePdf) {
+    for (const incomingPdf of incomingPdfs) {
+      await addAllPages(incomingPdf);
+    }
+  } else {
+    const baseDoc =
+      basePdf.doc ?? (await PDFDocument.load(basePdf.arrayBuffer));
+    const basePageCount = baseDoc.getPageCount();
+    const clampedInsertAt = Math.min(Math.max(insertAt, 0), basePageCount);
+
+    const basePages = await mergedDoc.copyPages(
+      baseDoc,
+      Array.from({ length: basePageCount }, (_, i) => i)
+    );
+
+    for (let i = 0; i < clampedInsertAt; i += 1) {
+      mergedDoc.addPage(basePages[i]);
+    }
+
+    for (const incomingPdf of incomingPdfs) {
+      await addAllPages(incomingPdf);
+    }
+
+    for (let i = clampedInsertAt; i < basePages.length; i += 1) {
+      mergedDoc.addPage(basePages[i]);
+    }
+  }
+
+  const bytes = await mergedDoc.save();
+  const buffer = pdfBytesToArrayBuffer(bytes);
+
+  return {
+    id: createId(),
+    name,
+    arrayBuffer: buffer,
+    pageCount: mergedDoc.getPageCount(),
+    doc: mergedDoc,
+  };
+}
+
 export async function splitIntoSinglePages(
   pdf: PdfFile
 ): Promise<SplitResult[]> {

src/pdf/pdfThumbnailService.ts

@@ -1,9 +1,4 @@
-import * as pdfjsLib from 'pdfjs-dist';
+import { pdfjsLib } from './pdfJs';
-import pdfjsWorker from 'pdfjs-dist/build/pdf.worker?worker&url';
-
-// pdf.js worker setup for Vite
-// eslint-disable-next-line @typescript-eslint/no-explicit-any
-(pdfjsLib as any).GlobalWorkerOptions.workerSrc = pdfjsWorker;
 
 type RotationsMap = Record<number, number>; // key: 0-based page index, value: degrees
 

src/pdf/pdfjsWorker.ts

@@ -0,0 +1,2 @@
+import './uint8ArrayToHexPolyfill';
+import 'pdfjs-dist/legacy/build/pdf.worker.mjs';

src/pdf/uint8ArrayToHexPolyfill.ts

@@ -0,0 +1,22 @@
+type Uint8ArrayWithToHex = Uint8Array & {
+  toHex?: () => string;
+};
+
+const uint8ArrayPrototype = Uint8Array.prototype as Uint8ArrayWithToHex;
+
+if (typeof uint8ArrayPrototype.toHex !== 'function') {
+  Object.defineProperty(Uint8Array.prototype, 'toHex', {
+    value: function toHex(this: Uint8Array): string {
+      const hex = new Array<string>(this.length);
+
+      for (let index = 0; index < this.length; index += 1) {
+        const value = this[index].toString(16);
+        hex[index] = value.length === 1 ? `0${value}` : value;
+      }
+
+      return hex.join('');
+    },
+    writable: true,
+    configurable: true,
+  });
+}

src/styles.css

@@ -12,89 +12,30 @@ body {
     BlinkMacSystemFont,
     'Segoe UI',
     sans-serif;
-  background-color: #f3f4f6;
+  background-color: var(--toolbox-background);
-  color: #111827;
+  color: var(--toolbox-text);
 }
 
 #root {
   min-height: 100vh;
 }
 
-.app-shell {
+.pdf-toolbox-shell .toolbox-shell__main .card {
-  display: flex;
+  border: 1px solid var(--pdf-border);
-  min-height: 100vh;
+  background: var(--pdf-surface);
-}
-
-.app-sidebar {
-  width: 260px;
-  background: #111827;
-  color: #e5e7eb;
-  padding: 1rem;
-  display: flex;
-  flex-direction: column;
-  gap: 1rem;
-}
-
-.app-sidebar h1 {
-  font-size: 1.1rem;
-  margin: 0;
-}
-
-.app-sidebar small {
-  color: #9ca3af;
-}
-
-.app-nav {
-  display: flex;
-  flex-direction: column;
-  gap: 0.25rem;
-}
-
-.app-nav button {
-  width: 100%;
-  text-align: left;
-  padding: 0.4rem 0.6rem;
-  border-radius: 0.375rem;
-  border: none;
-  background: transparent;
-  color: #d1d5db;
-  cursor: pointer;
-  font-size: 0.9rem;
-}
-
-.app-nav button.active {
-  background: #374151;
-  color: #f9fafb;
-}
-
-.app-nav button:disabled {
-  opacity: 0.5;
-  cursor: default;
-}
-
-.app-main {
-  flex: 1;
-  padding: 1rem 1.5rem;
-  display: flex;
-  flex-direction: column;
-  gap: 1rem;
-}
-
-.card {
-  background: white;
   border-radius: 0.75rem;
   padding: 1rem;
-  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.12);
+  box-shadow: var(--pdf-card-shadow);
 }
 
-.card h2 {
+.pdf-toolbox-shell .toolbox-shell__main .card h2 {
   margin-top: 0;
   font-size: 1rem;
 }
 
-button.primary {
+.pdf-toolbox-shell .toolbox-shell__main button.primary {
-  background: #2563eb;
+  background: var(--pdf-primary);
-  color: white;
+  color: var(--pdf-on-primary);
   border-radius: 0.5rem;
   padding: 0.45rem 0.9rem;
   border: none;
@@ -102,14 +43,14 @@ button.primary {
   font-size: 0.9rem;
 }
 
-button.primary:disabled {
+.pdf-toolbox-shell .toolbox-shell__main button.primary:disabled {
   opacity: 0.6;
   cursor: default;
 }
 
-button.secondary {
+.pdf-toolbox-shell .toolbox-shell__main button.secondary {
-  background: #e5e7eb;
+  background: var(--pdf-control);
-  color: #111827;
+  color: var(--pdf-control-text);
   border-radius: 0.5rem;
   padding: 0.45rem 0.9rem;
   border: none;
@@ -117,121 +58,175 @@ button.secondary {
   font-size: 0.9rem;
 }
 
-.button-row {
+.pdf-toolbox-shell .toolbox-shell__main .button-row {
   display: flex;
   flex-wrap: wrap;
   gap: 0.5rem;
   margin-top: 0.5rem;
 }
 
-.app-root {
+.pdf-toolbox-shell {
-  min-height: 100vh;
+  --pdf-surface: var(--toolbox-surface);
-  background-color: #f3f4f6;
+  --pdf-surface-soft: #f9fafb;
+  --pdf-surface-raised: #ffffff;
+  --pdf-text: var(--toolbox-text);
+  --pdf-muted: #4b5563;
+  --pdf-muted-soft: #6b7280;
+  --pdf-muted-faint: #9ca3af;
+  --pdf-border: #e5e7eb;
+  --pdf-border-strong: #d1d5db;
+  --pdf-primary: #2563eb;
+  --pdf-on-primary: #ffffff;
+  --pdf-control: #e5e7eb;
+  --pdf-control-text: #111827;
+  --pdf-info-surface: #eff6ff;
+  --pdf-info-border: #bfdbfe;
+  --pdf-info-text: #1e3a8a;
+  --pdf-success-surface: #ecfdf5;
+  --pdf-success-soft: #dcfce7;
+  --pdf-success-border: #86efac;
+  --pdf-success-text: #166534;
+  --pdf-warning-surface: #fff7ed;
+  --pdf-warning-border: #fed7aa;
+  --pdf-warning-text: #9a3412;
+  --pdf-danger-surface: #fef2f2;
+  --pdf-danger-soft: #fee2e2;
+  --pdf-danger-border: #fecaca;
+  --pdf-danger-text: #b91c1c;
+  --pdf-overlay: rgba(15, 23, 42, 0.62);
+  --pdf-dialog-shadow: 0 20px 40px rgba(15, 23, 42, 0.35);
+  --pdf-card-shadow: 0 1px 3px rgba(15, 23, 42, 0.12);
+  --pdf-paper: #ffffff;
+  --pdf-paper-placeholder: #f3f4f6;
+  --pdf-paper-border: #d1d5db;
+  --pdf-paper-text: #111827;
 }
 
-.app-header {
+.pdf-toolbox-shell[data-toolbox-theme='dark'] {
-  position: sticky;
+  --pdf-surface-soft: #20283a;
-  top: 0;
+  --pdf-surface-raised: #1b2334;
-  z-index: 10;
+  --pdf-muted: #b6bfd2;
-  background: #111827;
+  --pdf-muted-soft: #a9b3ca;
-  color: #e5e7eb;
+  --pdf-muted-faint: #8792aa;
-  padding: 0.6rem 1rem;
+  --pdf-border: #303a50;
-  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.4);
+  --pdf-border-strong: #465169;
+  --pdf-primary: #8798f5;
+  --pdf-on-primary: #101728;
+  --pdf-control: #293247;
+  --pdf-control-text: #edf1fb;
+  --pdf-info-surface: #182946;
+  --pdf-info-border: #345a8c;
+  --pdf-info-text: #c6dcff;
+  --pdf-success-surface: #12382e;
+  --pdf-success-soft: #174436;
+  --pdf-success-border: #33765d;
+  --pdf-success-text: #a7e8cf;
+  --pdf-warning-surface: #402814;
+  --pdf-warning-border: #80522d;
+  --pdf-warning-text: #ffd2a6;
+  --pdf-danger-surface: #421f29;
+  --pdf-danger-soft: #4f2530;
+  --pdf-danger-border: #81394b;
+  --pdf-danger-text: #ffc0cc;
+  --pdf-overlay: rgba(2, 6, 16, 0.76);
+  --pdf-dialog-shadow: 0 24px 52px rgba(0, 0, 0, 0.5);
+  --pdf-card-shadow: 0 2px 7px rgba(0, 0, 0, 0.26);
 }
 
-.app-header-title {
+@media (prefers-color-scheme: dark) {
-  display: flex;
+  .pdf-toolbox-shell[data-toolbox-theme='system'] {
-  align-items: center;
+    --pdf-surface-soft: #20283a;
-  gap: 0.6rem;
+    --pdf-surface-raised: #1b2334;
+    --pdf-muted: #b6bfd2;
+    --pdf-muted-soft: #a9b3ca;
+    --pdf-muted-faint: #8792aa;
+    --pdf-border: #303a50;
+    --pdf-border-strong: #465169;
+    --pdf-primary: #8798f5;
+    --pdf-on-primary: #101728;
+    --pdf-control: #293247;
+    --pdf-control-text: #edf1fb;
+    --pdf-info-surface: #182946;
+    --pdf-info-border: #345a8c;
+    --pdf-info-text: #c6dcff;
+    --pdf-success-surface: #12382e;
+    --pdf-success-soft: #174436;
+    --pdf-success-border: #33765d;
+    --pdf-success-text: #a7e8cf;
+    --pdf-warning-surface: #402814;
+    --pdf-warning-border: #80522d;
+    --pdf-warning-text: #ffd2a6;
+    --pdf-danger-surface: #421f29;
+    --pdf-danger-soft: #4f2530;
+    --pdf-danger-border: #81394b;
+    --pdf-danger-text: #ffc0cc;
+    --pdf-overlay: rgba(2, 6, 16, 0.76);
+    --pdf-dialog-shadow: 0 24px 52px rgba(0, 0, 0, 0.5);
+    --pdf-card-shadow: 0 2px 7px rgba(0, 0, 0, 0.26);
+  }
 }
 
-.app-header h1 {
+.pdf-toolbox-shell .toolbox-shell__main {
-  font-size: 1rem;
-  margin: 0;
-}
-
-.app-header small {
-  color: #9ca3af;
-  font-size: 0.8rem;
-}
-
-.app-logo {
-  font-size: 1.4rem;
-}
-
-.app-main {
   padding: 0.75rem;
-  max-width: 900px;
+  max-width: 90rem;
-  margin: 0 auto;
   display: flex;
   flex-direction: column;
   gap: 0.75rem;
 }
 
-/* Make cards full-width on mobile */
+.pdf-toolbox-shell .toolbox-shell__main input,
-.card {
+.pdf-toolbox-shell .toolbox-shell__main select,
+.pdf-toolbox-shell .toolbox-shell__main textarea {
+  border-color: var(--pdf-border-strong);
+  background: var(--pdf-surface);
+  color: var(--pdf-text);
+}
+
+.pdf-toolbox-shell .toolbox-shell__main input::placeholder,
+.pdf-toolbox-shell .toolbox-shell__main textarea::placeholder {
+  color: var(--pdf-muted-soft);
+}
+
+.pdf-toolbox-shell .toolbox-shell__main a {
+  color: var(--toolbox-accent);
+}
+
+.pdf-toolbox-shell .toolbox-shell__main a:hover {
+  color: var(--toolbox-accent-hover);
+}
+
+.pdf-toolbox-shell .toolbox-shell__main button:disabled {
+  opacity: 0.58;
+}
+
+.pdf-toolbox-shell .toolbox-shell__main button:focus-visible,
+.pdf-toolbox-shell .toolbox-shell__main a:focus-visible,
+.pdf-toolbox-shell .toolbox-shell__main input:focus-visible,
+.pdf-toolbox-shell .toolbox-shell__main select:focus-visible {
+  outline: 3px solid color-mix(in srgb, var(--toolbox-focus) 72%, transparent);
+  outline-offset: 2px;
+}
+
+.pdf-toolbox-shell .toolbox-shell__main .card {
   width: 100%;
 }
 
-.download-link {
+.pdf-toolbox-shell .toolbox-shell__main .download-link {
   display: inline-block;
   margin: 0.15rem 0;
   font-size: 0.85rem;
 }
 
-.card hr {
+.pdf-toolbox-shell .toolbox-shell__main .card hr {
   border: none;
-  border-top: 1px solid #e5e7eb;
+  border-top: 1px solid var(--pdf-border);
-}
-
-.app-header-content {
-  display: flex;
-  align-items: center;
-  justify-content: space-between;
-  gap: 1rem;
-}
-
-.app-version {
-  flex: 0 0 auto;
-  border-radius: 999px;
-  background: #374151;
-  color: #d1d5db;
-  padding: 0.4rem 0.7rem;
-  font-size: 0.85rem;
-  font-weight: 500;
-  line-height: 1;
-  white-space: nowrap;
-}
-
-.app-header-actions {
-  display: flex;
-  align-items: center;
-  gap: 0.5rem;
-}
-
-.app-help-button {
-  border: 1px solid #4b5563;
-  border-radius: 999px;
-  background: transparent;
-  color: #e5e7eb;
-  padding: 0.35rem 0.65rem;
-  font-size: 0.85rem;
-  font-weight: 500;
-  cursor: pointer;
-  line-height: 1;
-}
-
-.app-help-button:hover,
-.app-help-button:focus-visible {
-  background: #374151;
-  outline: none;
 }
 
 .help-dialog-backdrop {
   position: fixed;
   inset: 0;
   z-index: 80;
-  background: rgba(15, 23, 42, 0.65);
+  background: var(--pdf-overlay);
   display: flex;
   align-items: center;
   justify-content: center;
@@ -242,9 +237,9 @@ button.secondary {
   width: min(920px, 100%);
   max-height: min(88vh, 760px);
   overflow: auto;
-  background: #ffffff;
+  background: var(--pdf-surface-raised);
   border-radius: 0.9rem;
-  box-shadow: 0 24px 60px rgba(15, 23, 42, 0.4);
+  box-shadow: var(--pdf-dialog-shadow);
 }
 
 .help-dialog-header {
@@ -256,8 +251,8 @@ button.secondary {
   align-items: flex-start;
   gap: 1rem;
   padding: 1rem;
-  background: #ffffff;
+  background: var(--pdf-surface-raised);
-  border-bottom: 1px solid #e5e7eb;
+  border-bottom: 1px solid var(--pdf-border);
 }
 
 .help-dialog-header h2 {
@@ -267,7 +262,7 @@ button.secondary {
 
 .help-dialog-header p {
   margin: 0.35rem 0 0;
-  color: #4b5563;
+  color: var(--pdf-muted);
   font-size: 0.9rem;
   line-height: 1.45;
 }
@@ -278,8 +273,8 @@ button.secondary {
   border-radius: 999px;
   width: 2rem;
   height: 2rem;
-  background: #e5e7eb;
+  background: var(--pdf-control);
-  color: #111827;
+  color: var(--pdf-control-text);
   cursor: pointer;
   font-size: 1.25rem;
   line-height: 1;
@@ -293,10 +288,10 @@ button.secondary {
 }
 
 .help-section {
-  border: 1px solid #e5e7eb;
+  border: 1px solid var(--pdf-border);
   border-radius: 0.75rem;
   padding: 0.9rem;
-  background: #f9fafb;
+  background: var(--pdf-surface-soft);
 }
 
 .help-section h3 {
@@ -312,8 +307,8 @@ button.secondary {
 
 .help-step {
   border-radius: 0.65rem;
-  background: #ffffff;
+  background: var(--pdf-surface);
-  border: 1px solid #e5e7eb;
+  border: 1px solid var(--pdf-border);
   padding: 0.75rem;
 }
 
@@ -325,7 +320,7 @@ button.secondary {
 .help-step p,
 .help-note {
   margin: 0.35rem 0 0;
-  color: #4b5563;
+  color: var(--pdf-muted);
   font-size: 0.85rem;
   line-height: 1.45;
 }
@@ -341,18 +336,18 @@ button.secondary {
   display: inline-flex;
   justify-content: center;
   border-radius: 0.4rem;
-  border: 1px solid #d1d5db;
+  border: 1px solid var(--pdf-border-strong);
-  background: #ffffff;
+  background: var(--pdf-surface);
   padding: 0.2rem 0.45rem;
   font-size: 0.78rem;
   font-family: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;
-  color: #111827;
+  color: var(--pdf-text);
-  box-shadow: inset 0 -1px 0 #d1d5db;
+  box-shadow: inset 0 -1px 0 var(--pdf-border-strong);
   white-space: nowrap;
 }
 
 .shortcut-grid span {
-  color: #4b5563;
+  color: var(--pdf-muted);
   font-size: 0.85rem;
   line-height: 1.35;
 }
@@ -369,8 +364,8 @@ button.secondary {
 }
 
 .help-concepts dl > div {
-  background: #ffffff;
+  background: var(--pdf-surface);
-  border: 1px solid #e5e7eb;
+  border: 1px solid var(--pdf-border);
   border-radius: 0.65rem;
   padding: 0.75rem;
 }
@@ -383,7 +378,7 @@ button.secondary {
 
 .help-concepts dd {
   margin: 0;
-  color: #4b5563;
+  color: var(--pdf-muted);
   font-size: 0.82rem;
   line-height: 1.4;
 }
@@ -393,8 +388,95 @@ button.secondary {
   .help-concepts dl {
     grid-template-columns: 1fr;
   }
+}
 
-  .app-header-content {
+.merge-queue-list {
-    align-items: flex-start;
+  display: flex;
+  flex-direction: column;
+  gap: 0.5rem;
+  margin: 0.75rem 0;
+}
+
+.merge-queue-item {
+  display: grid;
+  grid-template-columns: auto 1fr auto;
+  align-items: center;
+  gap: 0.75rem;
+  border: 1px solid var(--pdf-info-border);
+  border-radius: 0.75rem;
+  background: color-mix(in srgb, var(--pdf-surface) 86%, transparent);
+  padding: 0.6rem;
+}
+
+.merge-queue-order {
+  border-radius: 999px;
+  background: var(--pdf-info-surface);
+  color: var(--pdf-info-text);
+  font-size: 0.8rem;
+  font-weight: 700;
+  padding: 0.2rem 0.5rem;
+}
+
+.merge-queue-details {
+  display: flex;
+  flex-direction: column;
+  gap: 0.1rem;
+  min-width: 0;
+  font-size: 0.9rem;
+}
+
+.merge-queue-details strong {
+  overflow-wrap: anywhere;
+}
+
+.merge-queue-details span {
+  color: var(--pdf-muted);
+  font-size: 0.8rem;
+}
+
+.merge-queue-actions {
+  display: flex;
+  flex-wrap: wrap;
+  justify-content: flex-end;
+  gap: 0.35rem;
+}
+
+.merge-queue-actions button.secondary {
+  padding: 0.3rem 0.55rem;
+  font-size: 0.8rem;
+}
+
+.merge-mode-group {
+  display: flex;
+  flex-direction: column;
+  gap: 0.5rem;
+  margin-top: 0.75rem;
+  font-size: 0.9rem;
+}
+
+.merge-mode-group label {
+  display: flex;
+  align-items: center;
+  gap: 0.4rem;
+}
+
+.merge-warning {
+  margin: 0.75rem 0 0;
+  border: 1px solid var(--pdf-warning-border);
+  border-radius: 0.5rem;
+  background: var(--pdf-warning-surface);
+  color: var(--pdf-warning-text);
+  padding: 0.55rem 0.65rem;
+  font-size: 0.85rem;
+}
+
+@media (max-width: 700px) {
+  .merge-queue-item {
+    grid-template-columns: 1fr;
+    align-items: stretch;
+  }
+
+  .merge-queue-actions {
+    justify-content: flex-start;
   }
 }

src/toolboxApp.definition.json

@@ -0,0 +1,29 @@
+{
+  "id": "de.add-ideas.pdf-tools",
+  "name": "PDF Workbench",
+  "description": "Page-level PDF operations performed locally in the browser.",
+  "entry": "./",
+  "icon": "./favicon.svg",
+  "categories": ["documents", "pdf"],
+  "tags": ["merge", "split", "rotate", "reorder"],
+  "integration": {
+    "contextVersion": 1,
+    "launchModes": ["navigate", "new-tab"],
+    "embedding": "unsupported"
+  },
+  "requirements": {
+    "secureContext": true,
+    "workers": true,
+    "indexedDb": true,
+    "crossOriginIsolated": false
+  },
+  "privacy": {
+    "processing": "local",
+    "fileUploads": false,
+    "telemetry": false
+  },
+  "source": {
+    "repository": "https://git.add-ideas.de/lotobo/pdf-tools",
+    "license": "AGPL-3.0-only"
+  }
+}

src/toolboxApp.test.ts

@@ -0,0 +1,17 @@
+import { describe, expect, it } from 'vitest';
+import { parseToolboxApp } from '@add-ideas/toolbox-contract';
+import generatedManifest from '../public/toolbox-app.json';
+import { toolboxApp } from './toolboxApp';
+
+describe('toolbox app definition', () => {
+  it('matches the generated public manifest', () => {
+    expect(toolboxApp).toEqual(parseToolboxApp(generatedManifest));
+  });
+
+  it('uses repository metadata for the shared source control', () => {
+    expect(toolboxApp.source?.repository).toBe(
+      'https://git.add-ideas.de/lotobo/pdf-tools'
+    );
+    expect(toolboxApp.actions).toBeUndefined();
+  });
+});

src/toolboxApp.ts

@@ -0,0 +1,9 @@
+import { parseToolboxApp } from '@add-ideas/toolbox-contract';
+import definition from './toolboxApp.definition.json';
+import { APP_VERSION } from './version';
+
+export const toolboxApp = parseToolboxApp({
+  schemaVersion: 1,
+  ...definition,
+  version: APP_VERSION,
+});

src/version.ts

@@ -1 +1 @@
-export const APP_VERSION = '0.3.1';
+export const APP_VERSION = '0.4.4';

tests/layoutStyles.test.ts

@@ -0,0 +1,13 @@
+import { readFile } from 'node:fs/promises';
+import { describe, expect, it } from 'vitest';
+
+describe('Toolbox layout styles', () => {
+  it('keeps the PDF workspace aligned to the 90rem shell width', async () => {
+    const stylesheet = await readFile('src/styles.css', 'utf8');
+    const mainRule = stylesheet.match(
+      /\.pdf-toolbox-shell \.toolbox-shell__main\s*\{(?<body>[^}]*)\}/u
+    );
+
+    expect(mainRule?.groups?.body).toMatch(/\bmax-width:\s*90rem\s*;/u);
+  });
+});

tests/releaseArchive.test.ts

@@ -0,0 +1,96 @@
+import { createHash } from 'node:crypto';
+import { spawnSync } from 'node:child_process';
+import {
+  mkdir,
+  mkdtemp,
+  readFile,
+  rm,
+  symlink,
+  writeFile,
+} from 'node:fs/promises';
+import os from 'node:os';
+import path from 'node:path';
+import { describe, expect, it } from 'vitest';
+import {
+  compareCodePoints,
+  collectDirectoryFiles,
+  createThirdPartyLicenseBundle,
+} from '../scripts/release-archive.mjs';
+
+describe('release archive helpers', () => {
+  it('sorts archive paths by code point', () => {
+    expect(['z', 'a', 'ä'].sort(compareCodePoints)).toEqual(['a', 'z', 'ä']);
+  });
+
+  it('creates identical ZIP bytes in different process timezones', () => {
+    const hashes = ['UTC', 'Europe/Berlin', 'America/New_York'].map(
+      (timezone) => {
+        const script = `
+          import { createHash } from 'node:crypto';
+          import { createDeterministicZip } from './scripts/release-archive.mjs';
+          const archive = createDeterministicZip({
+            'z.txt': Buffer.from('last'),
+            'a.txt': Buffer.from('first'),
+          });
+          process.stdout.write(createHash('sha256').update(archive).digest('hex'));
+        `;
+        const result = spawnSync(
+          process.execPath,
+          ['--input-type=module', '--eval', script],
+          {
+            cwd: process.cwd(),
+            encoding: 'utf8',
+            env: { ...process.env, TZ: timezone },
+          }
+        );
+        expect(result.status, result.stderr).toBe(0);
+        return result.stdout;
+      }
+    );
+    expect(new Set(hashes)).toHaveLength(1);
+  });
+
+  it('collects installed runtime license and notice texts', async () => {
+    const bundle = await createThirdPartyLicenseBundle(process.cwd(), [
+      'react',
+      'pdfjs-dist',
+      '@add-ideas/toolbox-contract',
+    ]);
+    const text = bundle.toString('utf8');
+    expect(text).toContain('react@');
+    expect(text).toContain('pdfjs-dist@');
+    expect(text).toContain('@add-ideas/toolbox-contract@');
+    expect(createHash('sha256').update(bundle).digest('hex')).toMatch(
+      /^[a-f0-9]{64}$/
+    );
+  });
+
+  it('rejects symbolic links in release input', async () => {
+    const temporaryDirectory = await mkdtemp(
+      path.join(os.tmpdir(), 'pdf-tools-release-')
+    );
+    try {
+      const outsideFile = path.join(temporaryDirectory, 'outside.txt');
+      const inputDirectory = path.join(temporaryDirectory, 'input');
+      await writeFile(outsideFile, 'private');
+      await mkdir(inputDirectory);
+      await symlink(outsideFile, path.join(inputDirectory, 'linked.txt'));
+
+      await expect(collectDirectoryFiles(inputDirectory)).rejects.toThrow(
+        'Unsupported filesystem entry in release input: linked.txt'
+      );
+    } finally {
+      await rm(temporaryDirectory, { recursive: true, force: true });
+    }
+  });
+
+  it('carries the embedded core-js license used by the PDF.js legacy build', async () => {
+    const license = await readFile(
+      'licenses/core-js-3.49.0-LICENSE.txt',
+      'utf8'
+    );
+    expect(license).toContain('core-js 3.49.0');
+    expect(license).toContain('CoreJS Company');
+    expect(license).toContain('Permission is hereby granted');
+  });
+});

vite.config.ts

@@ -2,9 +2,10 @@ import { defineConfig } from 'vite';
 import react from '@vitejs/plugin-react';
 
 export default defineConfig({
+  base: './',
   plugins: [react()],
   server: {
     host: true,
-    allowedHosts: ['pdftools.add-ideas.de'], // ← ADD THIS
+    allowedHosts: ['pdftools.add-ideas.de'],
   },
 });