diff --git a/src/app/(app)/layout.tsx b/src/app/(app)/layout.tsx
index dcf5127..c048fbf 100644
--- a/src/app/(app)/layout.tsx
+++ b/src/app/(app)/layout.tsx
@@ -3,6 +3,7 @@ import type { ReactNode } from 'react';
 import { Toaster } from 'react-hot-toast';
 
 import { Providers } from '@/app/providers';
+import { AppMain, AppShell } from '@/components/layout';
 import { getAuthBaseUrl, isAnonymousAuthSessionsEnabled, isGithubAuthEnabled } from '@/lib/server/auth/config';
 
 export const dynamic = 'force-dynamic';
@@ -32,9 +33,9 @@ export default function AppLayout({ children }: { children: ReactNode }) {
       allowAnonymousAuthSessions={allowAnonymousAuthSessions}
       githubAuthEnabled={githubAuthEnabled}
     >
-      <div className="app-shell h-dvh flex flex-col bg-background overflow-hidden">
-        <main className="flex-1 min-h-0 flex flex-col">{children}</main>
-      </div>
+      <AppShell>
+        <AppMain>{children}</AppMain>
+      </AppShell>
       <Toaster
         toastOptions={{
           style: {
diff --git a/src/app/(app)/signin/page.tsx b/src/app/(app)/signin/page.tsx
index a486df1..b5fb29b 100644
--- a/src/app/(app)/signin/page.tsx
+++ b/src/app/(app)/signin/page.tsx
@@ -1,7 +1,6 @@
 'use client';
 
 import { useState, useEffect, Suspense } from 'react';
-import { Button, Input } from '@headlessui/react';
 import { useRouter, useSearchParams } from 'next/navigation';
 import Link from 'next/link';
 import { getAuthClient } from '@/lib/client/auth-client';
@@ -10,7 +9,7 @@ import { useFeatureFlag } from '@/contexts/RuntimeConfigContext';
 import { showPrivacyModal } from '@/components/PrivacyModal';
 import { GithubIcon } from '@/components/icons/Icons';
 import { LoadingSpinner } from '@/components/Spinner';
-import { buttonClass } from '@/components/ui/buttonPrimitives';
+import { Button, Field, Input, Surface } from '@/components/ui';
 
 function SessionExpiredLoader({ setSessionExpired }: { setSessionExpired: (v: boolean) => void }) {
   const searchParams = useSearchParams();
@@ -120,7 +119,7 @@ function SignInContent() {
         <SessionExpiredLoader setSessionExpired={setSessionExpired} />
       </Suspense>
 
-        <div className="w-full max-w-md bg-surface rounded-lg shadow-elev-3 p-6">
+        <Surface elevation="3" className="w-full max-w-md p-6">
           <h1 className="text-xl font-semibold text-foreground">
             {sessionExpired ? 'Session Expired' : 'Connect Account'}
           </h1>
@@ -141,36 +140,32 @@ function SignInContent() {
 
         {error && (
           <div className="mt-4 p-3 bg-danger-wash border border-danger rounded-lg">
-            <p className="text-sm text-danger dark:text-danger">{error}</p>
+            <p className="text-sm text-danger">{error}</p>
           </div>
         )}
 
         <div className="mt-6 space-y-4">
           {/* Email */}
-          <div>
-            <label className="block text-sm font-medium text-foreground mb-1">Email</label>
+          <Field label="Email">
             <Input
               type="email"
               value={email}
               onChange={(e) => { setEmail(e.target.value); setError(null); }}
               placeholder="me@example.com"
-              className="w-full rounded-lg bg-background py-2 px-3 text-foreground shadow-elev-1
-                       focus:outline-none focus:ring-2 focus:ring-accent-line"
+              controlSize="lg"
             />
-          </div>
+          </Field>
 
           {/* Password */}
-          <div>
-            <label className="block text-sm font-medium text-foreground mb-1">Password</label>
+          <Field label="Password">
             <Input
               type="password"
               value={password}
               onChange={(e) => { setPassword(e.target.value); setError(null); }}
               placeholder="Password"
-              className="w-full rounded-lg bg-background py-2 px-3 text-foreground shadow-elev-1
-                       focus:outline-none focus:ring-2 focus:ring-accent-line"
+              controlSize="lg"
             />
-          </div>
+          </Field>
 
           {/* Remember Me */}
           <label className="flex items-center gap-2 cursor-pointer">
@@ -188,7 +183,9 @@ function SignInContent() {
             type="submit"
             disabled={isAnyLoading}
             onClick={handleSignIn}
-            className={buttonClass({ variant: 'primary', size: 'md', className: 'w-full' })}
+            variant="primary"
+            size="md"
+            className="w-full"
           >
             {loadingEmail ? <LoadingSpinner className="w-4 h-4 mx-auto" /> : 'Connect'}
           </Button>
@@ -199,11 +196,9 @@ function SignInContent() {
             type="button"
             disabled={isAnyLoading}
             onClick={handleGithubSignIn}
-            className={buttonClass({
-              variant: 'outline',
-              size: 'md',
-              className: 'w-full flex items-center justify-center gap-2',
-            })}
+            variant="outline"
+            size="md"
+            className="w-full gap-2"
           >
             {loadingGithub ? (
               <LoadingSpinner className="w-4 h-4" />
@@ -222,7 +217,9 @@ function SignInContent() {
               type="button"
               disabled={isAnyLoading}
               onClick={handleAnonymousContinue}
-              className={buttonClass({ variant: 'outline', size: 'md', className: 'w-full' })}
+              variant="outline"
+              size="md"
+              className="w-full"
             >
               {loadingAnonymous ? <LoadingSpinner className="w-4 h-4 mx-auto" /> : 'Continue anonymously'}
             </Button>
@@ -249,7 +246,7 @@ function SignInContent() {
             </button>
           </p>
         </div>
-      </div>
+      </Surface>
     </div>
   );
 }
diff --git a/src/app/(app)/signup/page.tsx b/src/app/(app)/signup/page.tsx
index 9dde55e..f2b1ad8 100644
--- a/src/app/(app)/signup/page.tsx
+++ b/src/app/(app)/signup/page.tsx
@@ -1,7 +1,6 @@
 'use client';
 
 import { useState } from 'react';
-import { Button, Input } from '@headlessui/react';
 import { useRouter } from 'next/navigation';
 import Link from 'next/link';
 import { getAuthClient } from '@/lib/client/auth-client';
@@ -9,7 +8,7 @@ import { useAuthConfig, useAuthRateLimit } from '@/contexts/AuthRateLimitContext
 import { useFeatureFlag } from '@/contexts/RuntimeConfigContext';
 import { showPrivacyModal } from '@/components/PrivacyModal';
 import { LoadingSpinner } from '@/components/Spinner';
-import { buttonClass } from '@/components/ui/buttonPrimitives';
+import { Button, Field, IconButton, Input, Surface } from '@/components/ui';
 import toast from 'react-hot-toast';
 
 export default function SignUpPage() {
@@ -105,7 +104,7 @@ export default function SignUpPage() {
   if (!enableUserSignups) {
     return (
       <div className="min-h-screen flex items-center justify-center p-4 bg-background">
-        <div className="w-full max-w-md bg-surface rounded-lg shadow-elev-3 p-6">
+        <Surface elevation="3" className="w-full max-w-md p-6">
           <h1 className="text-xl font-semibold text-foreground">Sign-ups unavailable</h1>
           <p className="text-sm text-soft mt-1">
             New account sign-ups are currently disabled by the site administrator.
@@ -118,7 +117,7 @@ export default function SignUpPage() {
               </Link>
             </p>
           </div>
-        </div>
+        </Surface>
       </div>
     );
   }
@@ -129,53 +128,45 @@ export default function SignUpPage() {
 
   return (
     <div className="min-h-screen flex items-center justify-center p-4 bg-background">
-      <div className="w-full max-w-md bg-surface rounded-lg shadow-elev-3 p-6">
+      <Surface elevation="3" className="w-full max-w-md p-6">
         <h1 className="text-xl font-semibold text-foreground">Sign Up</h1>
         <p className="text-sm text-soft mt-1">Create your account to get started</p>
 
         {error && (
           <div className="mt-4 p-3 bg-danger-wash border border-danger rounded-lg">
-            <p className="text-sm text-danger dark:text-danger">{error}</p>
+            <p className="text-sm text-danger">{error}</p>
           </div>
         )}
 
         <div className="mt-6 space-y-4">
           {/* Email */}
-          <div>
-            <label className="block text-sm font-medium text-foreground mb-1">Email</label>
+          <Field label="Email">
             <Input
               type="email"
               value={email}
               onChange={(e) => setEmail(e.target.value)}
               placeholder="me@example.com"
-              className="w-full rounded-lg bg-background py-2 px-3 text-foreground shadow-elev-1
-                       focus:outline-none focus:ring-2 focus:ring-accent-line"
+              controlSize="lg"
             />
-          </div>
+          </Field>
 
           {/* Password */}
-          <div>
-            <label className="block text-sm font-medium text-foreground mb-1">Password</label>
+          <Field label="Password">
             <div className="relative">
               <Input
                 type={showPassword ? 'text' : 'password'}
                 value={password}
                 onChange={(e) => setPassword(e.target.value)}
                 placeholder="Password"
-                className="w-full rounded-lg bg-background py-2 px-3 pr-10 text-foreground shadow-elev-1
-                         focus:outline-none focus:ring-2 focus:ring-accent-line"
+                controlSize="lg"
+                className="pr-10"
               />
-              <button
-                type="button"
+              <IconButton
                 onClick={() => setShowPassword(!showPassword)}
-                className={buttonClass({
-                  variant: 'ghost',
-                  size: 'icon',
-                  className: 'absolute right-2 top-1/2 -translate-y-1/2 h-7 w-7 text-soft',
-                })}
+                className="absolute right-2 top-1/2 h-7 w-7 -translate-y-1/2"
               >
                 {showPassword ? '👁️' : '👁️‍🗨️'}
-              </button>
+              </IconButton>
             </div>
 
             {/* Password Strength */}
@@ -209,32 +200,32 @@ export default function SignUpPage() {
                 </div>
               </div>
             )}
-          </div>
+          </Field>
 
           {/* Confirm Password */}
-          <div>
-            <label className="block text-sm font-medium text-foreground mb-1">Confirm Password</label>
+          <Field label="Confirm Password">
             <Input
               type={showPassword ? 'text' : 'password'}
               value={passwordConfirmation}
               onChange={(e) => setPasswordConfirmation(e.target.value)}
               placeholder="Confirm Password"
-              className="w-full rounded-lg bg-background py-2 px-3 text-foreground shadow-elev-1
-                       focus:outline-none focus:ring-2 focus:ring-accent-line"
+              controlSize="lg"
             />
             {passwordConfirmation && password && (
               <p className={`text-xs mt-1 ${password === passwordConfirmation ? 'text-accent' : 'text-danger'}`}>
                 {password === passwordConfirmation ? '✓ Passwords match' : '✗ Passwords do not match'}
               </p>
             )}
-          </div>
+          </Field>
 
           {/* Sign Up Button */}
           <Button
             type="submit"
             disabled={loading}
             onClick={handleSignUp}
-            className={buttonClass({ variant: 'primary', size: 'md', className: 'w-full' })}
+            variant="primary"
+            size="md"
+            className="w-full"
           >
             {loading ? <LoadingSpinner className="w-4 h-4 mx-auto" /> : 'Create Account'}
           </Button>
@@ -258,7 +249,7 @@ export default function SignUpPage() {
             </button>
           </p>
         </div>
-      </div>
+      </Surface>
     </div>
   );
 }
diff --git a/src/components/ConfirmDialog.tsx b/src/components/ConfirmDialog.tsx
index 40da54b..44213c2 100644
--- a/src/components/ConfirmDialog.tsx
+++ b/src/components/ConfirmDialog.tsx
@@ -1,6 +1,6 @@
 import { Fragment, KeyboardEvent } from 'react';
 import { Dialog, DialogPanel, DialogTitle, Transition, TransitionChild } from '@headlessui/react';
-import { buttonClass } from '@/components/ui/buttonPrimitives';
+import { Button, dialogPanelStyles } from '@/components/ui';
 
 interface ConfirmDialogProps {
   isOpen: boolean;
@@ -62,7 +62,7 @@ export function ConfirmDialog({
               leaveFrom="opacity-100 scale-100"
               leaveTo="opacity-0 scale-95"
             >
-              <DialogPanel role='dialog' className="w-full max-w-md transform rounded-lg bg-surface p-6 text-left align-middle shadow-elev-3 transition">
+              <DialogPanel role='dialog' className={dialogPanelStyles({ size: 'md' })}>
                 <DialogTitle
                   as="h3"
                   className="text-lg font-semibold leading-6 text-foreground"
@@ -74,27 +74,17 @@ export function ConfirmDialog({
                 </div>
 
                 <div className="mt-6 flex justify-end space-x-3">
-                  <button
-                    type="button"
-                    className={buttonClass({
-                      variant: 'outline',
-                      size: 'sm',
-                    })}
-                    onClick={onClose}
-                  >
+                  <Button variant="outline" size="sm" onClick={onClose}>
                     {cancelText}
-                  </button>
-                  <button
-                    type="button"
-                    className={buttonClass({
-                      variant: isDangerous ? 'danger' : 'primary',
-                      size: 'sm',
-                      className: 'text-wrap',
-                    })}
+                  </Button>
+                  <Button
+                    variant={isDangerous ? 'danger' : 'primary'}
+                    size="sm"
+                    className="text-wrap"
                     onClick={onConfirm}
                   >
                     {confirmText}
-                  </button>
+                  </Button>
                 </div>
               </DialogPanel>
             </TransitionChild>
diff --git a/src/components/Header.tsx b/src/components/Header.tsx
index a89ece1..e6394ef 100644
--- a/src/components/Header.tsx
+++ b/src/components/Header.tsx
@@ -1,3 +1,4 @@
+import { AppHeader } from '@/components/layout';
 import { ReactNode } from "react";
 
 export function Header({
@@ -9,19 +10,5 @@ export function Header({
   title?: ReactNode;
   right?: ReactNode;
 }) {
-  return (
-    <div className="sticky top-0 z-40 w-full border-b border-line-soft bg-surface" data-app-header>
-      <div className="px-2 sm:px-3 py-1 flex items-center justify-between gap-2 min-h-10">
-        <div className="flex items-center gap-2 min-w-0 flex-1">
-          {left}
-          {typeof title === 'string' ? (
-            <h1 className="text-xs md:text-sm font-semibold truncate text-foreground tracking-tight">{title}</h1>
-          ) : (
-            title
-          )}
-        </div>
-        <div className="flex items-center gap-2 min-w-0 justify-end">{right}</div>
-      </div>
-    </div>
-  );
+  return <AppHeader left={left} title={title} right={right} />;
 }
diff --git a/src/components/PrivacyModal.tsx b/src/components/PrivacyModal.tsx
index 43e4073..0c63c61 100644
--- a/src/components/PrivacyModal.tsx
+++ b/src/components/PrivacyModal.tsx
@@ -7,9 +7,9 @@ import {
   DialogTitle,
   Transition,
   TransitionChild,
-  Button,
 } from '@headlessui/react';
 import { updateAppConfig } from '@/lib/client/dexie';
+import { Button, dialogPanelStyles } from '@/components/ui';
 
 interface PrivacyModalProps {
   isOpen: boolean;
@@ -102,7 +102,7 @@ export function PrivacyModal({ isOpen, onAccept, onDismiss }: PrivacyModalProps)
               leaveFrom="opacity-100 scale-100"
               leaveTo="opacity-0 scale-95"
             >
-              <DialogPanel data-testid="privacy-modal" className="w-full max-w-md transform rounded-lg bg-surface p-6 text-left align-middle shadow-elev-3 transition">
+              <DialogPanel data-testid="privacy-modal" className={dialogPanelStyles({ size: 'md' })}>
                 <DialogTitle
                   as="h3"
                   className="text-lg font-semibold leading-6 text-foreground"
@@ -137,13 +137,9 @@ export function PrivacyModal({ isOpen, onAccept, onDismiss }: PrivacyModalProps)
                   <div className="flex justify-end">
                     <Button
                       data-testid="privacy-continue-button"
-                      type="button"
+                      variant="primary"
+                      size="lg"
                       disabled={!agreed}
-                      className="inline-flex justify-center rounded-lg bg-accent px-4 py-2 text-sm 
-                               font-medium text-background hover:bg-secondary-accent
-                               disabled:opacity-50 disabled:cursor-not-allowed
-                               focus:outline-none focus-visible:ring-2 focus-visible:ring-accent focus-visible:ring-offset-2
-                               transform transition-transform duration-base ease-standard"
                       onClick={handleAccept}
                     >
                       Continue
@@ -216,7 +212,7 @@ export function showPrivacyModal(): void {
                     leaveFrom="opacity-100 scale-100"
                     leaveTo="opacity-0 scale-95"
                   >
-                    <DialogPanel className="w-full max-w-md transform rounded-lg bg-surface p-6 text-left align-middle shadow-elev-3 transition">
+                    <DialogPanel className={dialogPanelStyles({ size: 'md' })}>
                       <DialogTitle
                         as="h3"
                         className="text-lg font-semibold leading-6 text-foreground"
@@ -228,11 +224,8 @@ export function showPrivacyModal(): void {
 
                       <div className="mt-6 flex justify-end">
                         <Button
-                          type="button"
-                          className="inline-flex justify-center rounded-lg bg-accent px-4 py-2 text-sm 
-                                   font-medium text-background hover:bg-secondary-accent focus:outline-none 
-                                   focus-visible:ring-2 focus-visible:ring-accent focus-visible:ring-offset-2
-                                   transform transition-transform duration-base ease-standard"
+                          variant="primary"
+                          size="lg"
                           onClick={handleClose}
                         >
                           Close
diff --git a/src/components/auth/AuthLoader.tsx b/src/components/auth/AuthLoader.tsx
index 2432b82..e429b1e 100644
--- a/src/components/auth/AuthLoader.tsx
+++ b/src/components/auth/AuthLoader.tsx
@@ -7,7 +7,7 @@ import { useAuthConfig, useAuthRateLimit } from '@/contexts/AuthRateLimitContext
 import { useAuthSession } from '@/hooks/useAuthSession';
 import { getAuthClient } from '@/lib/client/auth-client';
 import { LoadingSpinner } from '@/components/Spinner';
-import { buttonClass } from '@/components/ui/buttonPrimitives';
+import { Button } from '@/components/ui';
 
 function sleep(ms: number) {
   return new Promise<void>((resolve) => setTimeout(resolve, ms));
@@ -257,17 +257,17 @@ export function AuthLoader({ children }: { children: ReactNode }) {
         {bootstrapError ? (
           <div className="flex flex-col items-center gap-3">
             <p className="text-sm text-soft text-center">{bootstrapError}</p>
-            <button
-              type="button"
+            <Button
               onClick={() => {
                 attemptedForNullSessionRef.current = false;
                 setBootstrapError(null);
                 setRetryNonce((v) => v + 1);
               }}
-              className={buttonClass({ variant: 'primary', size: 'sm' })}
+              variant="primary"
+              size="sm"
             >
               Retry
-            </button>
+            </Button>
           </div>
         ) : (
           <p className="text-sm text-soft animate-pulse">
diff --git a/src/components/auth/ClaimDataModal.tsx b/src/components/auth/ClaimDataModal.tsx
index 4f6f6cf..fbfa02f 100644
--- a/src/components/auth/ClaimDataModal.tsx
+++ b/src/components/auth/ClaimDataModal.tsx
@@ -7,10 +7,10 @@ import {
   DialogTitle,
   Transition,
   TransitionChild,
-  Button,
 } from '@headlessui/react';
 import { useRouter } from 'next/navigation';
 import toast from 'react-hot-toast';
+import { Button, dialogPanelStyles } from '@/components/ui';
 
 export type ClaimableCounts = {
   documents: number;
@@ -99,7 +99,7 @@ export default function ClaimDataModal({
               leaveFrom="opacity-100 scale-100"
               leaveTo="opacity-0 scale-95"
             >
-              <DialogPanel data-testid="claim-modal" className="w-full max-w-md transform rounded-lg bg-surface p-6 text-left align-middle shadow-elev-3 transition">
+              <DialogPanel data-testid="claim-modal" className={dialogPanelStyles({ size: 'md' })}>
                 <DialogTitle
                   as="h3"
                   className="text-lg font-semibold leading-6 text-foreground mb-4"
@@ -129,27 +129,19 @@ export default function ClaimDataModal({
                 <div className="flex justify-end gap-3">
                   <Button
                     data-testid="claim-dismiss-button"
-                    type="button"
+                    variant="outline"
+                    size="sm"
                     onClick={onDismiss}
                     disabled={isClaiming}
-                    className="inline-flex justify-center rounded-lg bg-background px-3 py-1.5 text-sm
-                             font-medium text-foreground hover:bg-accent-wash focus:outline-none
-                             focus-visible:ring-2 focus-visible:ring-accent focus-visible:ring-offset-2
-                             transform transition-transform duration-base ease-standard hover:text-accent
-                             disabled:opacity-50"
                   >
                     Dismiss
                   </Button>
                   <Button
                     data-testid="claim-submit-button"
-                    type="button"
+                    variant="primary"
+                    size="sm"
                     onClick={handleClaim}
                     disabled={isClaiming}
-                    className="inline-flex justify-center rounded-lg bg-accent px-3 py-1.5 text-sm
-                             font-medium text-background hover:bg-secondary-accent focus:outline-none
-                             focus-visible:ring-2 focus-visible:ring-accent focus-visible:ring-offset-2
-                             transform transition-transform duration-base ease-standard hover:text-background
-                             disabled:opacity-50"
                   >
                     {isClaiming ? 'Claiming...' : 'Claim Data'}
                   </Button>
diff --git a/src/components/doclist/CreateFolderDialog.tsx b/src/components/doclist/CreateFolderDialog.tsx
index c66f7d1..9787811 100644
--- a/src/components/doclist/CreateFolderDialog.tsx
+++ b/src/components/doclist/CreateFolderDialog.tsx
@@ -1,5 +1,6 @@
 import { Fragment, KeyboardEvent } from 'react';
-import { Dialog, DialogPanel, DialogTitle, Input, Transition, TransitionChild } from '@headlessui/react';
+import { Dialog, DialogPanel, DialogTitle, Transition, TransitionChild } from '@headlessui/react';
+import { dialogPanelStyles, Input } from '@/components/ui';
 
 interface CreateFolderDialogProps {
   isOpen: boolean;
@@ -42,7 +43,7 @@ export function CreateFolderDialog({
               leaveFrom="opacity-100 scale-100"
               leaveTo="opacity-0 scale-95"
             >
-              <DialogPanel className="w-full max-w-md transform rounded-lg bg-surface p-6 text-left align-middle shadow-elev-3 transition">
+              <DialogPanel className={dialogPanelStyles({ size: 'md' })}>
                 <DialogTitle as="h3" className="text-lg font-semibold text-foreground">
                   Create New Folder
                 </DialogTitle>
@@ -53,7 +54,7 @@ export function CreateFolderDialog({
                     onChange={(e) => onFolderNameChange(e.target.value)}
                     onKeyDown={onKeyDown}
                     placeholder="Enter folder name"
-                    className="w-full rounded-lg bg-surface-sunken py-2 px-3 text-foreground shadow-elev-1 focus:outline-none focus:ring-1 focus:ring-accent-line"
+                    controlSize="lg"
                     autoFocus
                   />
                   <p className="mt-2 text-xs text-soft">Press Enter to create or Escape to cancel</p>
@@ -65,4 +66,4 @@ export function CreateFolderDialog({
       </Dialog>
     </Transition>
   );
-}
\ No newline at end of file
+}
diff --git a/src/components/doclist/views/GalleryView.tsx b/src/components/doclist/views/GalleryView.tsx
index 8077973..2941072 100644
--- a/src/components/doclist/views/GalleryView.tsx
+++ b/src/components/doclist/views/GalleryView.tsx
@@ -7,7 +7,7 @@ import type { DocumentListDocument } from '@/types/documents';
 import { PDFIcon, EPUBIcon, FileIcon } from '@/components/icons/Icons';
 import { DocumentPreview } from '@/components/doclist/DocumentPreview';
 import { formatDocumentSize } from '@/components/doclist/formatSize';
-import { buttonClass } from '@/components/ui/buttonPrimitives';
+import { buttonClass } from '@/components/ui';
 import { useDocumentSelection } from '../dnd/DocumentSelectionContext';
 import { DND_DOCUMENT, documentIdentityKey, type DocumentDragItem } from '../dnd/dndTypes';
 
diff --git a/src/components/doclist/window/FinderSidebar.tsx b/src/components/doclist/window/FinderSidebar.tsx
index e2f3614..ae95918 100644
--- a/src/components/doclist/window/FinderSidebar.tsx
+++ b/src/components/doclist/window/FinderSidebar.tsx
@@ -7,6 +7,7 @@ import type { Folder, SidebarFilter } from '@/types/documents';
 import { PDFIcon, EPUBIcon, FileIcon, DotsHorizontalIcon } from '@/components/icons/Icons';
 import { FolderIcon, HomeIcon, ClockIcon, FolderPlusIcon } from './finderIcons';
 import { DND_DOCUMENT, type DocumentDragItem } from '../dnd/dndTypes';
+import { IconButton, MenuItemClass, Sidebar as SidebarShell } from '@/components/ui';
 
 interface FinderSidebarProps {
   filter: SidebarFilter;
@@ -204,9 +205,9 @@ export function FinderSidebar({
   };
 
   return (
-    <aside
+    <SidebarShell
       style={{ '--sidebar-width': `${width}px` } as CSSProperties}
-      className="relative h-full w-full md:[width:var(--sidebar-width)] bg-surface border-r border-line-soft shrink-0 flex flex-col"
+      className="relative h-full w-full md:[width:var(--sidebar-width)] rounded-none border-y-0 border-l-0 border-r border-line-soft shadow-none shrink-0 flex flex-col"
     >
       <div className="min-h-0 flex-1 overflow-y-auto">
         <div className="p-2 flex flex-col gap-0.5">
@@ -272,7 +273,9 @@ export function FinderSidebar({
             rightSlot={(
               <Menu as="div" className="relative inline-flex items-center leading-none text-left shrink-0 normal-case tracking-normal font-normal">
                 <MenuButton
-                  className="inline-flex items-center justify-center h-3.5 w-5 rounded-sm text-soft hover:text-accent transition-colors duration-base ease-standard focus:outline-none"
+                  as={IconButton}
+                  size="xs"
+                  className="h-3.5 w-5"
                   title="Folder actions"
                   aria-label="Folder actions"
                 >
@@ -299,7 +302,7 @@ export function FinderSidebar({
                             onNewFolder();
                             onRowAction?.();
                           }}
-                          className={`${active ? 'bg-surface-sunken text-accent' : 'text-foreground'} group flex w-full items-center gap-2 rounded-md px-2 py-2 text-xs`}
+                          className={MenuItemClass(active)}
                         >
                           <FolderPlusIcon className="h-4 w-4" />
                           New Folder
@@ -315,7 +318,7 @@ export function FinderSidebar({
                             onRowAction?.();
                           }}
                           disabled={disabled}
-                          className={`${disabled ? 'text-faint cursor-not-allowed' : active ? 'bg-surface-sunken text-accent' : 'text-foreground'} group flex w-full items-center gap-2 rounded-md px-2 py-2 text-xs`}
+                          className={disabled ? 'flex w-full cursor-not-allowed items-center gap-2 rounded-md px-2 py-2 text-xs text-faint' : MenuItemClass(active)}
                         >
                           <svg className="h-4 w-4" fill="none" stroke="currentColor" viewBox="0 0 24 24">
                             <path strokeLinecap="round" strokeLinejoin="round" strokeWidth="2" d="M6 18L18 6M6 6l12 12" />
@@ -372,6 +375,6 @@ export function FinderSidebar({
         onPointerCancel={onResizeEnd}
         className="hidden md:block absolute top-0 right-0 h-full w-1 cursor-col-resize hover:bg-accent-wash active:bg-accent transition-colors duration-base ease-standard"
       />
-    </aside>
+    </SidebarShell>
   );
 }
diff --git a/src/components/doclist/window/FinderToolbar.tsx b/src/components/doclist/window/FinderToolbar.tsx
index 85fee30..6052ab2 100644
--- a/src/components/doclist/window/FinderToolbar.tsx
+++ b/src/components/doclist/window/FinderToolbar.tsx
@@ -10,6 +10,7 @@ import {
   HamburgerIcon,
 } from './finderIcons';
 import { ChevronUpDownIcon } from '@/components/icons/Icons';
+import { Toolbar, ToolbarButton, ToolbarGroup, ToolbarSegment, toolbarButtonStyles } from '@/components/ui';
 import type { ReactNode } from 'react';
 
 interface FinderToolbarProps {
@@ -52,22 +53,6 @@ const ICON_SIZES: Array<{ value: IconSize; label: string }> = [
   { value: 'xl', label: 'XL' },
 ];
 
-// Match SettingsModal / UserMenu trigger sizing exactly so all bar buttons share one rhythm.
-const TOOLBAR_BTN =
-  'inline-flex items-center py-1 px-2 rounded-md border bg-surface text-xs transition duration-base ease-standard';
-const TOOLBAR_BTN_INACTIVE =
-  'border-line text-foreground hover:text-accent hover:border-accent-line hover:bg-accent-wash';
-const TOOLBAR_BTN_ACTIVE = 'border-accent-line bg-surface-sunken text-accent';
-
-// Pill-grouped segmented control. Outer pill carries the border; inner segments are
-// borderless and rely on bg/text color to show active/hover. Sized so the whole pill
-// matches the height of a standalone TOOLBAR_BTN.
-const PILL = 'inline-flex items-center rounded-md border border-line bg-surface p-0.5 gap-0.5 shrink-0';
-const PILL_SEGMENT =
-  'inline-flex items-center justify-center rounded-sm text-xs transition-colors duration-base ease-standard';
-const PILL_SEGMENT_INACTIVE = 'text-soft hover:bg-accent-wash hover:text-accent';
-const PILL_SEGMENT_ACTIVE = 'bg-surface-sunken text-accent';
-
 export function FinderToolbar({
   viewMode,
   onViewModeChange,
@@ -89,26 +74,25 @@ export function FinderToolbar({
   const directionLabel = sortDirection === 'asc' ? currentSort.asc : currentSort.desc;
 
   return (
-    <div className="sticky top-0 z-40 w-full border-b border-line-soft bg-surface">
-      <div className="px-2 sm:px-3 py-1 min-h-10 flex items-center gap-1.5 sm:gap-2">
+    <Toolbar>
         {leftSlot && (
           <div className="shrink-0 flex items-center gap-2 pr-1 sm:pr-2 sm:border-r sm:border-line">
             {leftSlot}
           </div>
         )}
 
-        <button
-          type="button"
+        <ToolbarButton
           onClick={onToggleSidebar}
-          className={`${TOOLBAR_BTN} ${isSidebarOpen ? TOOLBAR_BTN_ACTIVE : TOOLBAR_BTN_INACTIVE} shrink-0`}
+          active={isSidebarOpen}
+          className="shrink-0"
           aria-pressed={isSidebarOpen}
           aria-label="Toggle sidebar"
           title="Toggle sidebar"
         >
           <HamburgerIcon className="w-4 h-4" />
-        </button>
+        </ToolbarButton>
 
-        <div className={PILL}>
+        <ToolbarGroup>
           {VIEW_BUTTONS.map(({ value, label, Icon }) => {
             const active = viewMode === value;
             const isIconsToggle = value === 'icons';
@@ -117,65 +101,52 @@ export function FinderToolbar({
                 key={value}
                 className={isIconsToggle ? 'relative group/icons inline-flex items-center' : 'inline-flex items-center'}
               >
-                <button
-                  type="button"
+                <ToolbarSegment
                   onClick={() => onViewModeChange(value)}
+                  active={active}
                   aria-pressed={active}
                   aria-label={`${label} view`}
                   title={`${label} view`}
-                  className={
-                    PILL_SEGMENT +
-                    ' h-6 w-7 ' +
-                    (active ? PILL_SEGMENT_ACTIVE : PILL_SEGMENT_INACTIVE)
-                  }
+                  className="w-7"
                 >
                   <Icon className="w-4 h-4" />
-                </button>
+                </ToolbarSegment>
                 {isIconsToggle && viewMode === 'icons' && (
                   <div
                     className="absolute top-full left-1/2 z-30 -translate-x-1/2 pt-1 opacity-0 pointer-events-none transition-opacity duration-fast group-hover/icons:opacity-100 group-hover/icons:pointer-events-auto group-focus-within/icons:opacity-100 group-focus-within/icons:pointer-events-auto"
                   >
-                    <div className={`${PILL} shadow-elev-2`}>
+                    <ToolbarGroup className="shadow-elev-2">
                       {ICON_SIZES.map(({ value: sizeValue, label: sizeLabel }) => {
                         const sizeActive = iconSize === sizeValue;
                         return (
-                          <button
+                          <ToolbarSegment
                             key={sizeValue}
-                            type="button"
                             onClick={() => onIconSizeChange(sizeValue)}
+                            active={sizeActive}
                             aria-pressed={sizeActive}
                             aria-label={`Icon size ${sizeLabel}`}
-                            className={
-                              PILL_SEGMENT +
-                              ' h-6 min-w-[26px] px-1.5 font-semibold tracking-wide ' +
-                              (sizeActive ? PILL_SEGMENT_ACTIVE : PILL_SEGMENT_INACTIVE)
-                            }
+                            className="min-w-[26px] px-1.5 font-semibold tracking-wide"
                           >
                             {sizeLabel}
-                          </button>
+                          </ToolbarSegment>
                         );
                       })}
-                    </div>
+                    </ToolbarGroup>
                   </div>
                 )}
               </div>
             );
           })}
-        </div>
+        </ToolbarGroup>
 
         {showSortControls && (
           <div className="flex items-center gap-1 shrink-0">
-            <button
-              type="button"
-              onClick={onSortDirectionToggle}
-              className={`${TOOLBAR_BTN} ${TOOLBAR_BTN_INACTIVE} whitespace-nowrap`}
-              title="Toggle sort direction"
-            >
+            <ToolbarButton onClick={onSortDirectionToggle} className="whitespace-nowrap" title="Toggle sort direction">
               {directionLabel}
-            </button>
+            </ToolbarButton>
             <Listbox value={sortBy} onChange={onSortByChange}>
               <ListboxButton
-                className={`${TOOLBAR_BTN} ${TOOLBAR_BTN_INACTIVE} gap-1 min-w-[90px] justify-between`}
+                className={toolbarButtonStyles({ className: 'gap-1 min-w-[90px] justify-between' })}
               >
                 <span>{currentSort.label}</span>
                 <ChevronUpDownIcon className="h-3 w-3 opacity-60" />
@@ -220,7 +191,6 @@ export function FinderToolbar({
             {rightSlot}
           </div>
         )}
-      </div>
-    </div>
+    </Toolbar>
   );
 }
diff --git a/src/components/doclist/window/FinderWindow.tsx b/src/components/doclist/window/FinderWindow.tsx
index c3f9bb5..2c10050 100644
--- a/src/components/doclist/window/FinderWindow.tsx
+++ b/src/components/doclist/window/FinderWindow.tsx
@@ -1,7 +1,7 @@
 'use client';
 
-import { Dialog, DialogPanel, Transition, TransitionChild } from '@headlessui/react';
-import { Fragment, useEffect, useState, type ReactNode } from 'react';
+import type { ReactNode } from 'react';
+import { LibraryFrame, useIsNarrow } from '@/components/layout';
 
 interface FinderWindowProps {
   toolbar: ReactNode;
@@ -14,22 +14,7 @@ interface FinderWindowProps {
   onRequestSidebarClose?: () => void;
 }
 
-const NARROW_QUERY = '(max-width: 767px)';
-
-export function useIsNarrow(): boolean {
-  const [isNarrow, setIsNarrow] = useState(() =>
-    typeof window !== 'undefined' ? window.matchMedia(NARROW_QUERY).matches : false,
-  );
-  useEffect(() => {
-    if (typeof window === 'undefined') return;
-    const mq = window.matchMedia(NARROW_QUERY);
-    const update = () => setIsNarrow(mq.matches);
-    update();
-    mq.addEventListener('change', update);
-    return () => mq.removeEventListener('change', update);
-  }, []);
-  return isNarrow;
-}
+export { useIsNarrow };
 
 /**
  * Finder-style file pane: sidebar + toolbar + content + status bar.
@@ -43,60 +28,15 @@ export function FinderWindow({
   sidebarOpen,
   onRequestSidebarClose,
 }: FinderWindowProps) {
-  const isNarrow = useIsNarrow();
-
   return (
-    <div className="flex flex-col h-full w-full bg-surface-sunken overflow-hidden">
-      {toolbar}
-
-      <div className="flex flex-1 min-h-0">
-        {!isNarrow && sidebarOpen && (
-          <div className="h-full">{sidebar}</div>
-        )}
-
-        <div className="flex-1 min-w-0 min-h-0 flex flex-col overflow-hidden">
-          {children}
-        </div>
-      </div>
-
-      {statusBar}
-
-      {/* Mobile drawer */}
-      <Transition show={isNarrow && sidebarOpen} as={Fragment}>
-        <Dialog
-          onClose={onRequestSidebarClose ?? (() => undefined)}
-          className="relative z-40 md:hidden"
-        >
-          <TransitionChild
-            as={Fragment}
-            enter="transition-opacity duration-fast"
-            enterFrom="opacity-0"
-            enterTo="opacity-100"
-            leave="transition-opacity duration-fast"
-            leaveFrom="opacity-100"
-            leaveTo="opacity-0"
-          >
-            <div className="fixed inset-0 bg-black/60 backdrop-blur-sm" />
-          </TransitionChild>
-          <div className="fixed inset-y-0 left-0 flex max-w-full">
-            <TransitionChild
-              as={Fragment}
-              enter="transition-transform duration-base ease-standard"
-              enterFrom="-translate-x-full"
-              enterTo="translate-x-0"
-              leave="transition-transform duration-fast ease-standard"
-              leaveFrom="translate-x-0"
-              leaveTo="-translate-x-full"
-            >
-              <DialogPanel
-                className="w-[80vw] max-w-[280px] h-full bg-surface shadow-elev-3"
-              >
-                {sidebar}
-              </DialogPanel>
-            </TransitionChild>
-          </div>
-        </Dialog>
-      </Transition>
-    </div>
+    <LibraryFrame
+      toolbar={toolbar}
+      sidebar={sidebar}
+      statusBar={statusBar}
+      sidebarOpen={sidebarOpen}
+      onRequestSidebarClose={onRequestSidebarClose}
+    >
+      {children}
+    </LibraryFrame>
   );
 }
diff --git a/src/components/documents/DexieMigrationModal.tsx b/src/components/documents/DexieMigrationModal.tsx
index f8dc6e1..6993eab 100644
--- a/src/components/documents/DexieMigrationModal.tsx
+++ b/src/components/documents/DexieMigrationModal.tsx
@@ -1,12 +1,13 @@
 'use client';
 
 import { Fragment, useCallback, useEffect, useState } from 'react';
-import { Dialog, DialogPanel, DialogTitle, Transition, TransitionChild, Button } from '@headlessui/react';
+import { Dialog, DialogPanel, DialogTitle, Transition, TransitionChild } from '@headlessui/react';
 import { getAllEpubDocuments, getAllHtmlDocuments, getAllPdfDocuments, updateAppConfig } from '@/lib/client/dexie';
 import { listDocuments, mimeTypeForDoc, uploadDocuments } from '@/lib/client/api/documents';
 import { useDocuments } from '@/contexts/DocumentContext';
 import type { BaseDocument } from '@/types/documents';
 import { cacheStoredDocumentFromBytes } from '@/lib/client/cache/documents';
+import { Button, dialogPanelStyles } from '@/components/ui';
 
 type DexieMigrationModalProps = {
   isOpen: boolean;
@@ -161,7 +162,7 @@ export function DexieMigrationModal({
               leaveFrom="opacity-100 scale-100"
               leaveTo="opacity-0 scale-95"
             >
-              <DialogPanel data-testid="migration-modal" className="w-full max-w-md transform rounded-lg bg-surface p-6 text-left align-middle shadow-elev-3 transition">
+              <DialogPanel data-testid="migration-modal" className={dialogPanelStyles({ size: 'md' })}>
                 <DialogTitle as="h3" className="text-lg font-semibold leading-6 text-foreground mb-4">
                   {title}
                 </DialogTitle>
@@ -187,24 +188,18 @@ export function DexieMigrationModal({
                 <div className="flex justify-end gap-3 mt-6">
                   <Button
                     data-testid="migration-skip-button"
+                    variant="outline"
+                    size="sm"
                     onClick={handleSkip}
                     disabled={isUploading}
-                    className="inline-flex justify-center rounded-lg bg-background px-3 py-1.5 text-sm
-                             font-medium text-foreground hover:bg-accent-wash focus:outline-none
-                             focus-visible:ring-2 focus-visible:ring-accent focus-visible:ring-offset-2
-                             transform transition-transform duration-base ease-standard hover:text-accent
-                             disabled:opacity-50"
                   >
                     Skip
                   </Button>
                   <Button
+                    variant="primary"
+                    size="sm"
                     onClick={handleUpload}
                     disabled={isUploading}
-                    className="inline-flex justify-center rounded-lg bg-accent px-3 py-1.5 text-sm
-                             font-medium text-background hover:bg-secondary-accent focus:outline-none
-                             focus-visible:ring-2 focus-visible:ring-accent focus-visible:ring-offset-2
-                             transform transition-transform duration-base ease-standard hover:text-background
-                             disabled:opacity-50"
                   >
                     {isUploading ? 'Uploading…' : 'Upload'}
                   </Button>
diff --git a/src/components/documents/DocumentSelectionModal.tsx b/src/components/documents/DocumentSelectionModal.tsx
index 5a29cda..4119f37 100644
--- a/src/components/documents/DocumentSelectionModal.tsx
+++ b/src/components/documents/DocumentSelectionModal.tsx
@@ -3,7 +3,7 @@
 import { Dialog, DialogPanel, DialogTitle, Transition, TransitionChild } from '@headlessui/react';
 import { Fragment, useEffect, useState } from 'react';
 import { BaseDocument } from '@/types/documents';
-import { buttonClass } from '@/components/ui/buttonPrimitives';
+import { Button, dialogPanelStyles } from '@/components/ui';
 
 interface DocumentSelectionModalProps {
   isOpen: boolean;
@@ -139,7 +139,7 @@ export function DocumentSelectionModal({
               leaveFrom="opacity-100 scale-100"
               leaveTo="opacity-0 scale-95"
             >
-              <DialogPanel className="w-full max-w-2xl transform rounded-lg bg-surface p-6 text-left align-middle shadow-elev-3 transition flex flex-col h-[80vh]">
+              <DialogPanel className={dialogPanelStyles({ size: 'lg', className: 'flex h-[80vh] flex-col' })}>
                 <DialogTitle
                   as="h3"
                   className="text-lg font-semibold leading-6 text-foreground mb-4 flex-shrink-0 flex justify-between items-center"
@@ -206,21 +206,17 @@ export function DocumentSelectionModal({
                 </div>
 
                 <div className="mt-4 flex justify-end gap-3 flex-shrink-0">
-                  <button
-                    type="button"
-                    className={buttonClass({ variant: 'outline', size: 'md' })}
-                    onClick={onClose}
-                  >
+                  <Button variant="outline" size="md" onClick={onClose}>
                     Cancel
-                  </button>
-                  <button
-                    type="button"
-                    className={buttonClass({ variant: 'primary', size: 'md' })}
+                  </Button>
+                  <Button
+                    variant="primary"
+                    size="md"
                     onClick={handleConfirmClick}
                     disabled={isLoading || selectedCount === 0 || isProcessing}
                   >
                     {isProcessing ? 'Processing...' : `${confirmLabel} ${selectedCount > 0 ? `(${selectedCount})` : ''}`}
-                  </button>
+                  </Button>
                 </div>
               </DialogPanel>
             </TransitionChild>
diff --git a/src/components/documents/DocumentUploader.tsx b/src/components/documents/DocumentUploader.tsx
index b83e682..4f1a07c 100644
--- a/src/components/documents/DocumentUploader.tsx
+++ b/src/components/documents/DocumentUploader.tsx
@@ -6,6 +6,7 @@ import { UploadIcon } from '@/components/icons/Icons';
 import { useDocuments } from '@/contexts/DocumentContext';
 import { uploadDocxAsPdf } from '@/lib/client/api/documents';
 import { useFeatureFlag } from '@/contexts/RuntimeConfigContext';
+import { dropzoneSurfaceClass } from '@/components/ui';
 
 interface DocumentUploaderProps {
   className?: string;
@@ -155,24 +156,7 @@ export function DocumentUploader({
     noKeyboard: variant === 'overlay'
   });
 
-  const containerBase = `group w-full rounded transition duration-base ease-standard ${
-    isUploading || isConverting ? 'cursor-not-allowed opacity-50' : 'cursor-pointer'
-  } ${className}`;
-
-  const borderBgClass =
-    variant === 'compact'
-      ? `${
-          isDragActive
-            ? 'border border-accent bg-surface-sunken text-accent'
-            : 'border border-dashed border-line text-foreground hover:border-accent hover:bg-accent-wash hover:text-accent'
-        }`
-      : `${
-          isDragActive
-            ? 'border-2 border-dashed border-accent bg-surface text-foreground'
-            : 'border-2 border-dashed border-muted bg-transparent text-foreground hover:border-accent hover:bg-surface'
-        }`;
-
-  const paddingClass = variant === 'compact' ? 'py-1 px-2 rounded-md' : 'py-5 px-3 rounded-lg';
+  const isDisabled = isUploading || isConverting;
 
   if (variant === 'overlay') {
     const rootProps = getRootProps();
@@ -183,7 +167,7 @@ export function DocumentUploader({
         {isDragActive && (
           <div className="absolute inset-0 z-50 flex flex-col items-center justify-center bg-surface backdrop-blur-md pointer-events-none p-6">
             <div className="w-full h-full border-2 border-dashed border-accent rounded-lg flex flex-col items-center justify-center bg-surface-solid text-center p-4">
-              <UploadIcon className="w-14 h-14 text-accent mb-4 animate-bounce" />
+              <UploadIcon className="w-14 h-14 text-accent mb-4" />
               <p className="text-xl font-bold text-foreground mb-1.5">
                 Drop files here to upload
               </p>
@@ -212,7 +196,12 @@ export function DocumentUploader({
   return (
     <div
       {...getRootProps()}
-      className={`${containerBase} ${borderBgClass} ${paddingClass}`}
+      className={dropzoneSurfaceClass({
+        variant: variant === 'compact' ? 'compact' : 'default',
+        active: isDragActive,
+        disabled: isDisabled,
+        className,
+      })}
     >
       <input {...getInputProps()} />
       {variant === 'compact' ? (
diff --git a/src/components/documents/ZoomControl.tsx b/src/components/documents/ZoomControl.tsx
index 014c2fa..0d88f0b 100644
--- a/src/components/documents/ZoomControl.tsx
+++ b/src/components/documents/ZoomControl.tsx
@@ -1,4 +1,4 @@
-import { buttonClass } from '@/components/ui/buttonPrimitives';
+import { buttonClass } from '@/components/ui';
 
 export function ZoomControl({
   value,
diff --git a/src/components/layout/AppHeader.tsx b/src/components/layout/AppHeader.tsx
new file mode 100644
index 0000000..7edc198
--- /dev/null
+++ b/src/components/layout/AppHeader.tsx
@@ -0,0 +1,30 @@
+import type { ReactNode } from 'react';
+import { cn } from '@/components/ui/cn';
+
+export function AppHeader({
+  left,
+  title,
+  right,
+  className,
+}: {
+  left?: ReactNode;
+  title?: ReactNode;
+  right?: ReactNode;
+  className?: string;
+}) {
+  return (
+    <div className={cn('sticky top-0 z-40 w-full border-b border-line-soft bg-surface', className)} data-app-header>
+      <div className="px-2 sm:px-3 py-1 flex items-center justify-between gap-2 min-h-10">
+        <div className="flex items-center gap-2 min-w-0 flex-1">
+          {left}
+          {typeof title === 'string' ? (
+            <h1 className="text-xs md:text-sm font-semibold truncate text-foreground tracking-tight">{title}</h1>
+          ) : (
+            title
+          )}
+        </div>
+        <div className="flex items-center gap-2 min-w-0 justify-end">{right}</div>
+      </div>
+    </div>
+  );
+}
diff --git a/src/components/layout/AppShell.tsx b/src/components/layout/AppShell.tsx
new file mode 100644
index 0000000..f636d11
--- /dev/null
+++ b/src/components/layout/AppShell.tsx
@@ -0,0 +1,14 @@
+import type { ReactNode } from 'react';
+import { cn } from '@/components/ui/cn';
+
+export function AppShell({ children, className }: { children: ReactNode; className?: string }) {
+  return (
+    <div className={cn('app-shell h-dvh flex flex-col bg-background overflow-hidden', className)}>
+      {children}
+    </div>
+  );
+}
+
+export function AppMain({ children, className }: { children: ReactNode; className?: string }) {
+  return <main className={cn('flex-1 min-h-0 flex flex-col', className)}>{children}</main>;
+}
diff --git a/src/components/layout/LibraryFrame.tsx b/src/components/layout/LibraryFrame.tsx
new file mode 100644
index 0000000..de1bad5
--- /dev/null
+++ b/src/components/layout/LibraryFrame.tsx
@@ -0,0 +1,99 @@
+'use client';
+
+import { Dialog, DialogPanel, Transition, TransitionChild } from '@headlessui/react';
+import { Fragment, useEffect, useState, type ReactNode } from 'react';
+import { cn } from '@/components/ui/cn';
+
+const NARROW_QUERY = '(max-width: 767px)';
+
+export function useIsNarrow(): boolean {
+  const [isNarrow, setIsNarrow] = useState(() =>
+    typeof window !== 'undefined' ? window.matchMedia(NARROW_QUERY).matches : false,
+  );
+  useEffect(() => {
+    if (typeof window === 'undefined') return;
+    const mq = window.matchMedia(NARROW_QUERY);
+    const update = () => setIsNarrow(mq.matches);
+    update();
+    mq.addEventListener('change', update);
+    return () => mq.removeEventListener('change', update);
+  }, []);
+  return isNarrow;
+}
+
+export function LibraryFrame({
+  toolbar,
+  sidebar,
+  statusBar,
+  children,
+  sidebarOpen,
+  onRequestSidebarClose,
+  className,
+}: {
+  toolbar: ReactNode;
+  sidebar: ReactNode;
+  statusBar: ReactNode;
+  children: ReactNode;
+  sidebarOpen: boolean;
+  onRequestSidebarClose?: () => void;
+  className?: string;
+}) {
+  const isNarrow = useIsNarrow();
+
+  return (
+    <div className={cn('flex h-full w-full flex-col overflow-hidden bg-surface-sunken', className)}>
+      {toolbar}
+      <div className="flex flex-1 min-h-0">
+        {!isNarrow && sidebarOpen && <div className="h-full">{sidebar}</div>}
+        <div className="flex-1 min-w-0 min-h-0 flex flex-col overflow-hidden">{children}</div>
+      </div>
+      {statusBar}
+      <LibrarySidebarDrawer open={isNarrow && sidebarOpen} onClose={onRequestSidebarClose}>
+        {sidebar}
+      </LibrarySidebarDrawer>
+    </div>
+  );
+}
+
+function LibrarySidebarDrawer({
+  open,
+  onClose,
+  children,
+}: {
+  open: boolean;
+  onClose?: () => void;
+  children: ReactNode;
+}) {
+  return (
+    <Transition show={open} as={Fragment}>
+      <Dialog onClose={onClose ?? (() => undefined)} className="relative z-40 md:hidden">
+        <TransitionChild
+          as={Fragment}
+          enter="transition-opacity duration-fast"
+          enterFrom="opacity-0"
+          enterTo="opacity-100"
+          leave="transition-opacity duration-fast"
+          leaveFrom="opacity-100"
+          leaveTo="opacity-0"
+        >
+          <div className="fixed inset-0 bg-black/60 backdrop-blur-sm" />
+        </TransitionChild>
+        <div className="fixed inset-y-0 left-0 flex max-w-full">
+          <TransitionChild
+            as={Fragment}
+            enter="transition-transform duration-base ease-standard"
+            enterFrom="-translate-x-full"
+            enterTo="translate-x-0"
+            leave="transition-transform duration-fast ease-standard"
+            leaveFrom="translate-x-0"
+            leaveTo="-translate-x-full"
+          >
+            <DialogPanel className="h-full w-[80vw] max-w-[280px] bg-surface shadow-elev-3">
+              {children}
+            </DialogPanel>
+          </TransitionChild>
+        </div>
+      </Dialog>
+    </Transition>
+  );
+}
diff --git a/src/components/layout/index.ts b/src/components/layout/index.ts
new file mode 100644
index 0000000..2c5bdf6
--- /dev/null
+++ b/src/components/layout/index.ts
@@ -0,0 +1,3 @@
+export * from './AppHeader';
+export * from './AppShell';
+export * from './LibraryFrame';
diff --git a/src/components/player/Navigator.tsx b/src/components/player/Navigator.tsx
index 5ac48dc..c43b295 100644
--- a/src/components/player/Navigator.tsx
+++ b/src/components/player/Navigator.tsx
@@ -1,7 +1,8 @@
 'use client';
 
-import { Button, Popover, PopoverButton, PopoverPanel } from '@headlessui/react';
+import { Popover, PopoverButton, PopoverPanel } from '@headlessui/react';
 import { useState, useEffect, useRef } from 'react';
+import { IconButton, Input, cn, popoverPanelClass, popoverTriggerClass } from '@/components/ui';
 
 export const Navigator = ({ currentPage, numPages, skipToLocation }: {
   currentPage: number;
@@ -53,36 +54,37 @@ export const Navigator = ({ currentPage, numPages, skipToLocation }: {
   return (
     <div className="flex items-center space-x-1">
       {/* Page back */}
-      <Button
+      <IconButton
         onClick={() => skipToLocation(currentPage - 1, true)}
         disabled={currentPage <= 1}
-        className="relative p-2 rounded-full text-foreground hover:bg-accent-wash data-[hover]:bg-accent-wash data-[active]:bg-accent-wash transition duration-base focus:outline-none disabled:opacity-50 transform ease-standard hover:text-accent"
+        className="rounded-full"
         aria-label="Previous page"
       >
         <svg className="h-4 w-4" viewBox="0 0 24 24" fill="none" stroke="currentColor">
           <path strokeLinecap="round" strokeLinejoin="round" strokeWidth="2" d="M11 19l-7-7m0 0l7-7m-7 7h18" />
         </svg>
-      </Button>
+      </IconButton>
 
       {/* Page number popup */}
       <Popover className="relative mb-1">
         <PopoverButton
-          className="bg-surface-sunken px-2 py-0.5 rounded-full focus:outline-none cursor-pointer hover:bg-accent-wash transform transition-transform duration-base ease-standard hover:text-accent"
+          className={cn(popoverTriggerClass, 'rounded-full bg-surface-sunken px-2 py-0.5 text-xs')}
           onClick={handlePopoverOpen}
         >
           <p className="text-xs whitespace-nowrap">
             {currentPage} / {numPages || 1}
           </p>
         </PopoverButton>
-        <PopoverPanel anchor="top" className="absolute z-50 bg-surface p-3 rounded-md shadow-elev-2 border border-line">
+        <PopoverPanel anchor="top" className={popoverPanelClass}>
           <div className="flex flex-col space-y-2">
             <div className="text-xs font-medium text-foreground">Go to page</div>
-            <input
+            <Input
               ref={inputRef}
               type="text"
               inputMode="numeric"
               pattern="[0-9]*"
-              className="w-20 px-2 py-1 text-xs text-accent bg-surface-sunken rounded border-none outline-none appearance-none text-center"
+              controlSize="sm"
+              className="w-20 appearance-none border-none text-center text-accent"
               value={inputValue}
               onChange={handleInputChange}
               onBlur={handleInputConfirm}
@@ -96,16 +98,16 @@ export const Navigator = ({ currentPage, numPages, skipToLocation }: {
       </Popover>
 
       {/* Page forward */}
-      <Button
+      <IconButton
         onClick={() => skipToLocation(currentPage + 1, true)}
         disabled={currentPage >= (numPages || 1)}
-        className="relative p-2 rounded-full text-foreground hover:bg-accent-wash data-[hover]:bg-accent-wash data-[active]:bg-accent-wash transition duration-base focus:outline-none disabled:opacity-50 transform ease-standard hover:text-accent"
+        className="rounded-full"
         aria-label="Next page"
       >
         <svg className="h-4 w-4" viewBox="0 0 24 24" fill="none" stroke="currentColor">
           <path strokeLinecap="round" strokeLinejoin="round" strokeWidth="2" d="M13 5l7 7-7 7M5 5l7 7-7 7" />
         </svg>
-      </Button>
+      </IconButton>
     </div>
   );
 }
diff --git a/src/components/player/RateLimitPauseButton.tsx b/src/components/player/RateLimitPauseButton.tsx
index 44be7e9..7f4a9e5 100644
--- a/src/components/player/RateLimitPauseButton.tsx
+++ b/src/components/player/RateLimitPauseButton.tsx
@@ -1,8 +1,8 @@
 'use client';
 
-import { Button } from '@headlessui/react';
 import { PauseIcon } from '@/components/icons/Icons';
 import { useTTS } from '@/contexts/TTSContext';
+import { IconButton } from '@/components/ui';
 
 export function RateLimitPauseButton() {
   const { isPlaying, togglePlay } = useTTS();
@@ -12,14 +12,13 @@ export function RateLimitPauseButton() {
   if (!isPlaying) return null;
 
   return (
-    <Button
+    <IconButton
       onClick={() => {
         if (isPlaying) togglePlay();
       }}
-      className="relative p-1.5 rounded-md text-foreground hover:bg-accent-wash transition duration-base focus:outline-none h-8 w-8 flex items-center justify-center transform ease-standard hover:text-accent"
       aria-label="Pause"
     >
       <PauseIcon className="w-5 h-5" />
-    </Button>
+    </IconButton>
   );
 }
diff --git a/src/components/player/SpeedControl.tsx b/src/components/player/SpeedControl.tsx
index 2da7074..eae7f04 100644
--- a/src/components/player/SpeedControl.tsx
+++ b/src/components/player/SpeedControl.tsx
@@ -1,10 +1,11 @@
 'use client';
 
-import { Input, Popover, PopoverButton, PopoverPanel } from '@headlessui/react';
+import { Popover, PopoverButton, PopoverPanel } from '@headlessui/react';
 import { ChevronUpDownIcon, SpeedometerIcon } from '@/components/icons/Icons';
 import { useConfig } from '@/contexts/ConfigContext';
 import { useCallback, useEffect, useMemo, useState } from 'react';
 import { resolveTtsProviderModelPolicy } from '@/lib/shared/tts-provider-policy';
+import { popoverPanelClass, popoverTriggerClass, rangeInputClass } from '@/components/ui';
 
 export const SpeedControl = ({ 
   setSpeedAndRestart, 
@@ -88,13 +89,13 @@ export const SpeedControl = ({
 
   return (
     <Popover className="relative">
-      <PopoverButton className="flex items-center space-x-0.5 sm:space-x-1 bg-transparent text-foreground text-xs sm:text-sm focus:outline-none cursor-pointer hover:bg-accent-wash rounded pl-1.5 sm:pl-2 pr-0.5 sm:pr-1 py-0.5 sm:py-1 transform transition-transform duration-base ease-standard hover:text-accent">
+      <PopoverButton className={`${popoverTriggerClass} space-x-0.5 px-1.5 py-0.5 text-xs sm:space-x-1 sm:px-2 sm:py-1 sm:text-sm`}>
         <SpeedometerIcon className="h-3 w-3 sm:h-3.5 sm:w-3.5" />
         <span className="sm:hidden">{compactTriggerLabel}</span>
         <span className="hidden sm:inline">{triggerLabel}</span>
         <ChevronUpDownIcon className="h-2.5 w-2.5 sm:h-3 sm:w-3" />
       </PopoverButton>
-      <PopoverPanel anchor="top" className="absolute z-50 bg-surface p-3 rounded-md shadow-elev-2 border border-line">
+      <PopoverPanel anchor="top" className={popoverPanelClass}>
         <div className="flex flex-col space-y-4">
           {!nativeSpeedSupported && (
             <div className="rounded-md border border-line bg-background px-2 py-1.5 text-[11px] text-soft">
@@ -112,7 +113,7 @@ export const SpeedControl = ({
                 </span>
                 <span className="text-xs">{max.toFixed(1)}x</span>
               </div>
-              <Input
+              <input
                 type="range"
                 min={min}
                 max={max}
@@ -122,7 +123,7 @@ export const SpeedControl = ({
                 onMouseUp={handleVoiceSpeedChangeComplete}
                 onKeyUp={handleVoiceSpeedChangeComplete}
                 onTouchEnd={handleVoiceSpeedChangeComplete}
-                className="w-full bg-surface-sunken rounded-lg appearance-none cursor-pointer accent-accent [&::-webkit-slider-runnable-track]:bg-surface-sunken [&::-webkit-slider-runnable-track]:rounded-lg [&::-webkit-slider-thumb]:appearance-none [&::-webkit-slider-thumb]:h-4 [&::-webkit-slider-thumb]:w-4 [&::-webkit-slider-thumb]:rounded-full [&::-webkit-slider-thumb]:bg-accent [&::-moz-range-track]:bg-surface-sunken [&::-moz-range-track]:rounded-lg [&::-moz-range-thumb]:appearance-none [&::-moz-range-thumb]:h-4 [&::-moz-range-thumb]:w-4 [&::-moz-range-thumb]:rounded-full [&::-moz-range-thumb]:bg-accent"
+                className={rangeInputClass}
               />
             </div>
           )}
@@ -136,7 +137,7 @@ export const SpeedControl = ({
               </span>
               <span className="text-xs">{max.toFixed(1)}x</span>
             </div>
-            <Input
+            <input
               type="range"
               min={min}
               max={max}
@@ -146,7 +147,7 @@ export const SpeedControl = ({
               onMouseUp={handleAudioSpeedChangeComplete}
               onKeyUp={handleAudioSpeedChangeComplete}
               onTouchEnd={handleAudioSpeedChangeComplete}
-              className="w-full bg-surface-sunken rounded-lg appearance-none cursor-pointer accent-accent [&::-webkit-slider-runnable-track]:bg-surface-sunken [&::-webkit-slider-runnable-track]:rounded-lg [&::-webkit-slider-thumb]:appearance-none [&::-webkit-slider-thumb]:h-4 [&::-webkit-slider-thumb]:w-4 [&::-webkit-slider-thumb]:rounded-full [&::-webkit-slider-thumb]:bg-accent [&::-moz-range-track]:bg-surface-sunken [&::-moz-range-track]:rounded-lg [&::-moz-range-thumb]:appearance-none [&::-moz-range-thumb]:h-4 [&::-moz-range-thumb]:w-4 [&::-moz-range-thumb]:rounded-full [&::-moz-range-thumb]:bg-accent"
+              className={rangeInputClass}
             />
           </div>
         </div>
diff --git a/src/components/player/TTSPlayer.tsx b/src/components/player/TTSPlayer.tsx
index 2554413..94dea14 100644
--- a/src/components/player/TTSPlayer.tsx
+++ b/src/components/player/TTSPlayer.tsx
@@ -1,7 +1,6 @@
 'use client';
 
 import { useTTS } from '@/contexts/TTSContext';
-import { Button } from '@headlessui/react';
 import {
   PlayIcon,
   PauseIcon,
@@ -12,6 +11,7 @@ import { LoadingSpinner } from '@/components/Spinner';
 import { VoicesControl } from '@/components/player/VoicesControl';
 import { SpeedControl } from '@/components/player/SpeedControl';
 import { Navigator } from '@/components/player/Navigator';
+import { IconButton } from '@/components/ui';
 
 export default function TTSPlayer({ currentPage, numPages }: {
   currentPage?: number;
@@ -49,32 +49,29 @@ export default function TTSPlayer({ currentPage, numPages }: {
         )}
 
         {/* Playback Controls */}
-        <Button
+        <IconButton
           onClick={skipBackward}
-          className="relative p-1.5 rounded-md text-foreground hover:bg-accent-wash transition duration-base focus:outline-none disabled:opacity-50 h-8 w-8 flex items-center justify-center transform ease-standard hover:text-accent"
           aria-label="Skip backward"
           disabled={isProcessing}
         >
           {isProcessing ? <LoadingSpinner /> : <SkipBackwardIcon className="w-5 h-5" />}
-        </Button>
+        </IconButton>
 
-        <Button
+        <IconButton
           onClick={togglePlay}
-          className="relative p-1.5 rounded-md text-foreground hover:bg-accent-wash transition duration-base focus:outline-none h-8 w-8 flex items-center justify-center transform ease-standard hover:text-accent"
           aria-label={isPlaying ? 'Pause' : 'Play'}
           disabled={isProcessing && !isPlaying}
         >
           {isPlaying ? <PauseIcon className="w-5 h-5" /> : <PlayIcon className="w-5 h-5" />}
-        </Button>
+        </IconButton>
 
-        <Button
+        <IconButton
           onClick={skipForward}
-          className="relative p-1.5 rounded-md text-foreground hover:bg-accent-wash transition duration-base focus:outline-none disabled:opacity-50 h-8 w-8 flex items-center justify-center transform ease-standard hover:text-accent"
           aria-label="Skip forward"
           disabled={isProcessing}
         >
           {isProcessing ? <LoadingSpinner /> : <SkipForwardIcon className="w-5 h-5" />}
-        </Button>
+        </IconButton>
 
         {/* Voice control */}
         <VoicesControl availableVoices={availableVoices} setVoiceAndRestart={setVoiceAndRestart} />
diff --git a/src/components/ui/dropzone.ts b/src/components/ui/dropzone.ts
new file mode 100644
index 0000000..d0498fd
--- /dev/null
+++ b/src/components/ui/dropzone.ts
@@ -0,0 +1,40 @@
+import { cn } from './cn';
+import { variants } from './variants';
+
+export type DropzoneVariant = 'default' | 'compact';
+
+export const dropzoneStyles = variants({
+  base: 'group w-full cursor-pointer border-dashed text-foreground transition-colors duration-base ease-standard disabled:pointer-events-none disabled:cursor-not-allowed disabled:opacity-50',
+  variants: {
+    variant: {
+      default: 'rounded-lg border-2 px-3 py-5',
+      compact: 'rounded-md border px-2 py-1',
+    },
+    active: {
+      true: 'border-accent bg-surface text-accent',
+      false: 'border-line bg-transparent hover:border-accent hover:bg-accent-wash hover:text-accent',
+    },
+  },
+  defaults: {
+    variant: 'default',
+    active: 'false',
+  },
+});
+
+export function dropzoneSurfaceClass({
+  variant = 'default',
+  active = false,
+  disabled = false,
+  className,
+}: {
+  variant?: DropzoneVariant;
+  active?: boolean;
+  disabled?: boolean;
+  className?: string;
+}) {
+  return dropzoneStyles({
+    variant,
+    active: active ? 'true' : 'false',
+    className: cn(disabled && 'cursor-not-allowed opacity-50', className),
+  });
+}
diff --git a/src/components/ui/icon-button.tsx b/src/components/ui/icon-button.tsx
index a2442cb..d89f9ed 100644
--- a/src/components/ui/icon-button.tsx
+++ b/src/components/ui/icon-button.tsx
@@ -1,4 +1,4 @@
-import type { ButtonHTMLAttributes, ReactNode } from 'react';
+import { forwardRef, type ButtonHTMLAttributes, type ReactNode } from 'react';
 import { cn } from './cn';
 import { variants } from './variants';
 import { focusRing, motionColors } from './tokens';
@@ -27,21 +27,21 @@ export const iconButtonStyles = variants({
   },
 });
 
-export function IconButton({
+export const IconButton = forwardRef<HTMLButtonElement, ButtonHTMLAttributes<HTMLButtonElement> & {
+  children: ReactNode;
+  tone?: IconButtonTone;
+  size?: IconButtonSize;
+}>(function IconButton({
   className,
   children,
   tone = 'ghost',
   size = 'md',
   type = 'button',
   ...props
-}: ButtonHTMLAttributes<HTMLButtonElement> & {
-  children: ReactNode;
-  tone?: IconButtonTone;
-  size?: IconButtonSize;
-}) {
+}, ref) {
   return (
-    <button type={type} className={iconButtonStyles({ tone, size, className })} {...props}>
+    <button ref={ref} type={type} className={iconButtonStyles({ tone, size, className })} {...props}>
       {children}
     </button>
   );
-}
+});
diff --git a/src/components/ui/index.ts b/src/components/ui/index.ts
index cf218f0..da14cf7 100644
--- a/src/components/ui/index.ts
+++ b/src/components/ui/index.ts
@@ -3,10 +3,13 @@ export * from './button';
 export * from './cn';
 export * from './dialog';
 export * from './divider';
+export * from './dropzone';
 export * from './field';
 export * from './icon-button';
 export * from './input';
 export * from './menu';
+export * from './popover';
+export * from './range';
 export * from './section';
 export * from './select';
 export * from './sidebar';
diff --git a/src/components/ui/input.tsx b/src/components/ui/input.tsx
index a252595..9d59894 100644
--- a/src/components/ui/input.tsx
+++ b/src/components/ui/input.tsx
@@ -1,4 +1,4 @@
-import type { InputHTMLAttributes, TextareaHTMLAttributes } from 'react';
+import { forwardRef, type InputHTMLAttributes, type TextareaHTMLAttributes } from 'react';
 import { cn } from './cn';
 import { variants } from './variants';
 import { motionColors } from './tokens';
@@ -21,13 +21,13 @@ export const inputStyles = variants({
 
 export const inputClass = inputStyles();
 
-export function Input({
+export const Input = forwardRef<HTMLInputElement, InputHTMLAttributes<HTMLInputElement> & { controlSize?: InputControlSize }>(function Input({
   className,
   controlSize = 'md',
   ...props
-}: InputHTMLAttributes<HTMLInputElement> & { controlSize?: InputControlSize }) {
-  return <input className={inputStyles({ size: controlSize, className })} {...props} />;
-}
+}, ref) {
+  return <input ref={ref} className={inputStyles({ size: controlSize, className })} {...props} />;
+});
 
 export function Textarea({
   className,
diff --git a/src/components/ui/popover.ts b/src/components/ui/popover.ts
new file mode 100644
index 0000000..9f219d6
--- /dev/null
+++ b/src/components/ui/popover.ts
@@ -0,0 +1,9 @@
+import { cn } from './cn';
+
+export const popoverPanelClass = cn(
+  'z-50 rounded-md border border-line bg-surface p-3 shadow-elev-2 focus:outline-none',
+);
+
+export const popoverTriggerClass = cn(
+  'inline-flex items-center rounded-md text-foreground hover:bg-accent-wash hover:text-accent focus:outline-none transition-colors duration-fast ease-standard',
+);
diff --git a/src/components/ui/range.ts b/src/components/ui/range.ts
new file mode 100644
index 0000000..37818f0
--- /dev/null
+++ b/src/components/ui/range.ts
@@ -0,0 +1,9 @@
+import { cn } from './cn';
+
+export const rangeInputClass = cn(
+  'w-full cursor-pointer appearance-none rounded-lg bg-surface-sunken accent-accent',
+  '[&::-webkit-slider-runnable-track]:h-1.5 [&::-webkit-slider-runnable-track]:rounded-lg [&::-webkit-slider-runnable-track]:bg-surface-sunken',
+  '[&::-webkit-slider-thumb]:h-4 [&::-webkit-slider-thumb]:w-4 [&::-webkit-slider-thumb]:appearance-none [&::-webkit-slider-thumb]:rounded-full [&::-webkit-slider-thumb]:bg-accent',
+  '[&::-moz-range-track]:h-1.5 [&::-moz-range-track]:rounded-lg [&::-moz-range-track]:bg-surface-sunken',
+  '[&::-moz-range-thumb]:h-4 [&::-moz-range-thumb]:w-4 [&::-moz-range-thumb]:appearance-none [&::-moz-range-thumb]:rounded-full [&::-moz-range-thumb]:border-0 [&::-moz-range-thumb]:bg-accent',
+);
diff --git a/src/components/ui/toolbar.tsx b/src/components/ui/toolbar.tsx
index 0b6369b..a91a052 100644
--- a/src/components/ui/toolbar.tsx
+++ b/src/components/ui/toolbar.tsx
@@ -1,4 +1,4 @@
-import type { HTMLAttributes, ReactNode } from 'react';
+import type { ButtonHTMLAttributes, HTMLAttributes, ReactNode } from 'react';
 import { cn } from './cn';
 import { variants } from './variants';
 import { motionColors } from './tokens';
@@ -34,7 +34,7 @@ export function ToolbarButton({
   children,
   type = 'button',
   ...props
-}: React.ButtonHTMLAttributes<HTMLButtonElement> & {
+}: ButtonHTMLAttributes<HTMLButtonElement> & {
   active?: boolean;
   children: ReactNode;
 }) {
@@ -63,7 +63,7 @@ export function ToolbarSegment({
   children,
   type = 'button',
   ...props
-}: React.ButtonHTMLAttributes<HTMLButtonElement> & {
+}: ButtonHTMLAttributes<HTMLButtonElement> & {
   active?: boolean;
   children: ReactNode;
 }) {