feat: enhance mobile responsiveness with collapsible controls and automation/effects bars

Added comprehensive mobile support for Phase 15 (Polish & Optimization):

**Mobile Layout Enhancements:**
- Track controls now collapsible on mobile with two states:
  - Collapsed: minimal controls with expand chevron, R/M/S buttons, horizontal level meter
  - Expanded: full height fader, pan control, all buttons
- Track collapse buttons added to mobile view (left chevron for track collapse, right chevron for control collapse)
- Master controls collapse button hidden on desktop (lg:hidden)
- Automation and effects bars now available on mobile layout
- Both bars collapsible with eye/eye-off icons, horizontally scrollable when zoomed
- Mobile vertical stacking: controls → waveform → automation → effects per track

**Bug Fixes:**
- Fixed track controls and waveform container height matching on desktop
- Fixed Modal component prop: isOpen → open in all dialog components
- Fixed TypeScript null check for audioBuffer.duration
- Fixed keyboard shortcut category: 'help' → 'view'

**Technical Improvements:**
- Consistent height calculation using trackHeight variable
- Proper responsive breakpoints with Tailwind (sm:640px, lg:1024px)
- Progressive disclosure pattern for mobile controls

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

components/controls/MasterControls.tsx

@@ -1,6 +1,7 @@
 'use client';
 
 import * as React from 'react';
+import { ChevronDown, ChevronUp } from 'lucide-react';
 import { CircularKnob } from '@/components/ui/CircularKnob';
 import { MasterFader } from './MasterFader';
 import { cn } from '@/lib/utils/cn';
@@ -12,10 +13,12 @@ export interface MasterControlsProps {
   rmsLevel: number;
   isClipping: boolean;
   isMuted?: boolean;
+  collapsed?: boolean; // For collapsible on mobile/small screens
   onVolumeChange: (volume: number) => void;
   onPanChange: (pan: number) => void;
   onMuteToggle: () => void;
   onResetClip?: () => void;
+  onToggleCollapse?: () => void;
   className?: string;
 }
 
@@ -26,21 +29,82 @@ export function MasterControls({
   rmsLevel,
   isClipping,
   isMuted = false,
+  collapsed = false,
   onVolumeChange,
   onPanChange,
   onMuteToggle,
   onResetClip,
+  onToggleCollapse,
   className,
 }: MasterControlsProps) {
+  // Collapsed view - minimal controls
+  if (collapsed) {
+    return (
+      <div className={cn(
+        'flex flex-col items-center gap-2 px-3 py-2 bg-card/50 border border-accent/50 rounded-lg w-full',
+        className
+      )}>
+        <div className="flex items-center justify-between w-full">
+          <div className="text-xs font-bold text-accent uppercase tracking-wider">
+            Master
+          </div>
+          {onToggleCollapse && (
+            <button
+              onClick={onToggleCollapse}
+              className="p-1 hover:bg-accent/20 rounded transition-colors"
+              title="Expand master controls"
+            >
+              <ChevronDown className="h-3 w-3 text-muted-foreground" />
+            </button>
+          )}
+        </div>
+        <div className="flex items-center gap-2 w-full justify-center">
+          <button
+            onClick={onMuteToggle}
+            className={cn(
+              'h-7 w-7 rounded-md flex items-center justify-center transition-all text-xs font-bold',
+              isMuted
+                ? 'bg-blue-500 text-white shadow-md shadow-blue-500/30'
+                : 'bg-card hover:bg-accent text-muted-foreground border border-border/50'
+            )}
+            title={isMuted ? 'Unmute' : 'Mute'}
+          >
+            M
+          </button>
+          <div className="flex-1 h-2 bg-muted rounded-full overflow-hidden">
+            <div
+              className={cn(
+                'h-full transition-all',
+                peakLevel > 0.95 ? 'bg-red-500' : peakLevel > 0.8 ? 'bg-yellow-500' : 'bg-green-500'
+              )}
+              style={{ width: `${peakLevel * 100}%` }}
+            />
+          </div>
+        </div>
+      </div>
+    );
+  }
+
   return (
     <div className={cn(
       'flex flex-col items-center gap-3 px-4 py-3 bg-card/50 border-2 border-accent/50 rounded-lg',
       className
     )}>
-      {/* Master Label */}
-      <div className="text-[10px] font-bold text-accent uppercase tracking-wider">
+      {/* Master Label with collapse button */}
+      <div className="flex items-center justify-between w-full">
+        <div className="text-[10px] font-bold text-accent uppercase tracking-wider flex-1 text-center">
           Master
         </div>
+        {onToggleCollapse && (
+          <button
+            onClick={onToggleCollapse}
+            className="p-0.5 hover:bg-accent/20 rounded transition-colors flex-shrink-0 lg:hidden"
+            title="Collapse master controls"
+          >
+            <ChevronUp className="h-3 w-3 text-muted-foreground" />
+          </button>
+        )}
+      </div>
 
       {/* Pan Control */}
       <CircularKnob

components/dialogs/BrowserCompatDialog.tsx

@@ -0,0 +1,130 @@
+'use client';
+
+import * as React from 'react';
+import { AlertTriangle, XCircle, Info, X } from 'lucide-react';
+import { Modal } from '@/components/ui/Modal';
+import { Button } from '@/components/ui/Button';
+import { getBrowserInfo } from '@/lib/utils/browser-compat';
+
+interface BrowserCompatDialogProps {
+  open: boolean;
+  missingFeatures: string[];
+  warnings: string[];
+  onClose: () => void;
+}
+
+export function BrowserCompatDialog({
+  open,
+  missingFeatures,
+  warnings,
+  onClose,
+}: BrowserCompatDialogProps) {
+  const [browserInfo, setBrowserInfo] = React.useState({ name: 'Unknown', version: 'Unknown' });
+  const hasErrors = missingFeatures.length > 0;
+
+  // Get browser info only on client side
+  React.useEffect(() => {
+    setBrowserInfo(getBrowserInfo());
+  }, []);
+
+  if (!open) return null;
+
+  return (
+    <Modal open={open} onClose={onClose} title="">
+      <div className="p-6 max-w-md">
+        {/* Header */}
+        <div className="flex items-start justify-between mb-4">
+          <div className="flex items-center gap-2">
+            {hasErrors ? (
+              <>
+                <XCircle className="h-5 w-5 text-destructive" />
+                <h2 className="text-lg font-semibold">Browser Not Supported</h2>
+              </>
+            ) : (
+              <>
+                <AlertTriangle className="h-5 w-5 text-yellow-500" />
+                <h2 className="text-lg font-semibold">Browser Warnings</h2>
+              </>
+            )}
+          </div>
+          <button onClick={onClose} className="text-muted-foreground hover:text-foreground">
+            <X className="h-4 w-4" />
+          </button>
+        </div>
+
+        <p className="text-sm text-muted-foreground mb-4">
+          {hasErrors ? (
+            <>Your browser is missing required features to run this audio editor.</>
+          ) : (
+            <>Some features may not work as expected in your browser.</>
+          )}
+        </p>
+
+        <div className="space-y-4">
+          {/* Browser Info */}
+          <div className="flex items-center gap-2 text-sm text-muted-foreground">
+            <Info className="h-4 w-4" />
+            <span>
+              {browserInfo.name} {browserInfo.version}
+            </span>
+          </div>
+
+          {/* Missing Features */}
+          {missingFeatures.length > 0 && (
+            <div className="space-y-2">
+              <h3 className="text-sm font-semibold text-destructive flex items-center gap-2">
+                <XCircle className="h-4 w-4" />
+                Missing Required Features:
+              </h3>
+              <ul className="list-disc list-inside space-y-1 text-sm text-muted-foreground">
+                {missingFeatures.map((feature) => (
+                  <li key={feature}>{feature}</li>
+                ))}
+              </ul>
+            </div>
+          )}
+
+          {/* Warnings */}
+          {warnings.length > 0 && (
+            <div className="space-y-2">
+              <h3 className="text-sm font-semibold text-yellow-600 dark:text-yellow-500 flex items-center gap-2">
+                <AlertTriangle className="h-4 w-4" />
+                Warnings:
+              </h3>
+              <ul className="list-disc list-inside space-y-1 text-sm text-muted-foreground">
+                {warnings.map((warning) => (
+                  <li key={warning}>{warning}</li>
+                ))}
+              </ul>
+            </div>
+          )}
+
+          {/* Recommendations */}
+          {hasErrors && (
+            <div className="bg-muted/50 border border-border rounded-md p-3 space-y-2">
+              <h3 className="text-sm font-semibold">Recommended Browsers:</h3>
+              <ul className="text-sm text-muted-foreground space-y-1">
+                <li>• Chrome 90+ or Edge 90+</li>
+                <li>• Firefox 88+</li>
+                <li>• Safari 14+</li>
+              </ul>
+            </div>
+          )}
+
+          {/* Actions */}
+          <div className="flex justify-end gap-2">
+            {hasErrors ? (
+              <Button onClick={onClose} variant="destructive">
+                Close
+              </Button>
+            ) : (
+              <Button onClick={onClose}>
+                Continue Anyway
+              </Button>
+            )}
+          </div>
+        </div>
+      </div>
+    </Modal>
+  );
+}

components/dialogs/KeyboardShortcutsDialog.tsx

@@ -0,0 +1,140 @@
+'use client';
+
+import * as React from 'react';
+import { Keyboard, X } from 'lucide-react';
+import { Modal } from '@/components/ui/Modal';
+import { Button } from '@/components/ui/Button';
+import { cn } from '@/lib/utils/cn';
+
+export interface KeyboardShortcutsDialogProps {
+  open: boolean;
+  onClose: () => void;
+}
+
+interface ShortcutCategory {
+  name: string;
+  shortcuts: Array<{
+    keys: string[];
+    description: string;
+  }>;
+}
+
+const SHORTCUTS: ShortcutCategory[] = [
+  {
+    name: 'Playback',
+    shortcuts: [
+      { keys: ['Space'], description: 'Play / Pause' },
+      { keys: ['Home'], description: 'Go to Start' },
+      { keys: ['End'], description: 'Go to End' },
+      { keys: ['←'], description: 'Seek Backward' },
+      { keys: ['→'], description: 'Seek Forward' },
+      { keys: ['Ctrl', '←'], description: 'Seek Backward 5s' },
+      { keys: ['Ctrl', '→'], description: 'Seek Forward 5s' },
+    ],
+  },
+  {
+    name: 'Edit',
+    shortcuts: [
+      { keys: ['Ctrl', 'Z'], description: 'Undo' },
+      { keys: ['Ctrl', 'Shift', 'Z'], description: 'Redo' },
+      { keys: ['Ctrl', 'X'], description: 'Cut' },
+      { keys: ['Ctrl', 'C'], description: 'Copy' },
+      { keys: ['Ctrl', 'V'], description: 'Paste' },
+      { keys: ['Delete'], description: 'Delete Selection' },
+      { keys: ['Ctrl', 'D'], description: 'Duplicate' },
+      { keys: ['Ctrl', 'A'], description: 'Select All' },
+    ],
+  },
+  {
+    name: 'View',
+    shortcuts: [
+      { keys: ['Ctrl', '+'], description: 'Zoom In' },
+      { keys: ['Ctrl', '-'], description: 'Zoom Out' },
+      { keys: ['Ctrl', '0'], description: 'Fit to View' },
+    ],
+  },
+  {
+    name: 'File',
+    shortcuts: [
+      { keys: ['Ctrl', 'S'], description: 'Save Project' },
+      { keys: ['Ctrl', 'K'], description: 'Open Command Palette' },
+    ],
+  },
+];
+
+function KeyboardKey({ keyName }: { keyName: string }) {
+  return (
+    <kbd className="px-2 py-1 text-xs font-semibold bg-muted border border-border rounded shadow-sm min-w-[2rem] text-center inline-block">
+      {keyName}
+    </kbd>
+  );
+}
+
+export function KeyboardShortcutsDialog({ open, onClose }: KeyboardShortcutsDialogProps) {
+  if (!open) return null;
+
+  return (
+    <Modal open={open} onClose={onClose} title="">
+      <div className="p-6 max-w-2xl">
+        {/* Header */}
+        <div className="flex items-start justify-between mb-6">
+          <div className="flex items-center gap-3">
+            <Keyboard className="h-6 w-6 text-primary" />
+            <h2 className="text-xl font-semibold">Keyboard Shortcuts</h2>
+          </div>
+          <button onClick={onClose} className="text-muted-foreground hover:text-foreground">
+            <X className="h-5 w-5" />
+          </button>
+        </div>
+
+        {/* Shortcuts Grid */}
+        <div className="grid grid-cols-1 md:grid-cols-2 gap-6">
+          {SHORTCUTS.map((category) => (
+            <div key={category.name} className="space-y-3">
+              <h3 className="text-sm font-semibold text-primary border-b border-border pb-2">
+                {category.name}
+              </h3>
+              <div className="space-y-2">
+                {category.shortcuts.map((shortcut, index) => (
+                  <div
+                    key={index}
+                    className="flex items-center justify-between gap-4 py-1.5"
+                  >
+                    <span className="text-sm text-foreground flex-1">
+                      {shortcut.description}
+                    </span>
+                    <div className="flex items-center gap-1 flex-shrink-0">
+                      {shortcut.keys.map((key, keyIndex) => (
+                        <React.Fragment key={keyIndex}>
+                          {keyIndex > 0 && (
+                            <span className="text-muted-foreground text-xs mx-0.5">+</span>
+                          )}
+                          <KeyboardKey keyName={key} />
+                        </React.Fragment>
+                      ))}
+                    </div>
+                  </div>
+                ))}
+              </div>
+            </div>
+          ))}
+        </div>
+
+        {/* Footer */}
+        <div className="mt-6 pt-4 border-t border-border">
+          <p className="text-xs text-muted-foreground text-center">
+            Press <KeyboardKey keyName="Ctrl" /> + <KeyboardKey keyName="K" /> to open the
+            command palette and search for more actions
+          </p>
+        </div>
+
+        {/* Close Button */}
+        <div className="mt-6 flex justify-end">
+          <Button onClick={onClose} variant="default">
+            Close
+          </Button>
+        </div>
+      </div>
+    </Modal>
+  );
+}

components/dialogs/MemoryWarningDialog.tsx

@@ -0,0 +1,101 @@
+'use client';
+
+import * as React from 'react';
+import { AlertTriangle, Info, X } from 'lucide-react';
+import { Modal } from '@/components/ui/Modal';
+import { Button } from '@/components/ui/Button';
+import { formatMemorySize } from '@/lib/utils/memory-limits';
+
+interface MemoryWarningDialogProps {
+  open: boolean;
+  estimatedMemoryMB: number;
+  availableMemoryMB?: number;
+  warning: string;
+  fileName?: string;
+  onContinue: () => void;
+  onCancel: () => void;
+}
+
+export function MemoryWarningDialog({
+  open,
+  estimatedMemoryMB,
+  availableMemoryMB,
+  warning,
+  fileName,
+  onContinue,
+  onCancel,
+}: MemoryWarningDialogProps) {
+  if (!open) return null;
+
+  const estimatedBytes = estimatedMemoryMB * 1024 * 1024;
+  const availableBytes = availableMemoryMB ? availableMemoryMB * 1024 * 1024 : undefined;
+
+  return (
+    <Modal open={open} onClose={onCancel} title="">
+      <div className="p-6 max-w-md">
+        {/* Header */}
+        <div className="flex items-start justify-between mb-4">
+          <div className="flex items-center gap-2">
+            <AlertTriangle className="h-5 w-5 text-yellow-500" />
+            <h2 className="text-lg font-semibold">Memory Warning</h2>
+          </div>
+          <button onClick={onCancel} className="text-muted-foreground hover:text-foreground">
+            <X className="h-4 w-4" />
+          </button>
+        </div>
+
+        <p className="text-sm text-muted-foreground mb-4">
+          {warning}
+        </p>
+
+        <div className="space-y-4">
+          {/* File Info */}
+          {fileName && (
+            <div className="flex items-center gap-2 text-sm">
+              <Info className="h-4 w-4 text-muted-foreground" />
+              <span className="font-medium">File:</span>
+              <span className="text-muted-foreground truncate">{fileName}</span>
+            </div>
+          )}
+
+          {/* Memory Details */}
+          <div className="bg-muted/50 border border-border rounded-md p-3 space-y-2">
+            <div className="flex justify-between text-sm">
+              <span className="text-muted-foreground">Estimated Memory:</span>
+              <span className="font-medium">{formatMemorySize(estimatedBytes)}</span>
+            </div>
+            {availableBytes && (
+              <div className="flex justify-between text-sm">
+                <span className="text-muted-foreground">Available Memory:</span>
+                <span className="font-medium">{formatMemorySize(availableBytes)}</span>
+              </div>
+            )}
+          </div>
+
+          {/* Warning Message */}
+          <div className="bg-yellow-500/10 border border-yellow-500/20 rounded-md p-3">
+            <p className="text-sm text-yellow-700 dark:text-yellow-400">
+              <strong>Note:</strong> Loading large files may cause performance issues or browser crashes,
+              especially on devices with limited memory. Consider:
+            </p>
+            <ul className="mt-2 text-sm text-yellow-700 dark:text-yellow-400 space-y-1 list-disc list-inside">
+              <li>Closing other browser tabs</li>
+              <li>Using a shorter audio file</li>
+              <li>Splitting large files into smaller segments</li>
+            </ul>
+          </div>
+
+          {/* Actions */}
+          <div className="flex justify-end gap-2">
+            <Button onClick={onCancel} variant="outline">
+              Cancel
+            </Button>
+            <Button onClick={onContinue} variant="default">
+              Continue Anyway
+            </Button>
+          </div>
+        </div>
+      </div>
+    </Modal>
+  );
+}

components/dialogs/UnsupportedFormatDialog.tsx

@@ -0,0 +1,106 @@
+'use client';
+
+import * as React from 'react';
+import { AlertCircle, FileQuestion, X } from 'lucide-react';
+import { Modal } from '@/components/ui/Modal';
+import { Button } from '@/components/ui/Button';
+
+export interface UnsupportedFormatDialogProps {
+  open: boolean;
+  fileName: string;
+  fileType: string;
+  onClose: () => void;
+}
+
+const SUPPORTED_FORMATS = [
+  { extension: 'WAV', mimeType: 'audio/wav', description: 'Lossless, widely supported' },
+  { extension: 'MP3', mimeType: 'audio/mpeg', description: 'Compressed, universal support' },
+  { extension: 'OGG', mimeType: 'audio/ogg', description: 'Free, open format' },
+  { extension: 'FLAC', mimeType: 'audio/flac', description: 'Lossless compression' },
+  { extension: 'M4A/AAC', mimeType: 'audio/aac', description: 'Apple audio format' },
+  { extension: 'AIFF', mimeType: 'audio/aiff', description: 'Apple lossless format' },
+  { extension: 'WebM', mimeType: 'audio/webm', description: 'Modern web format' },
+];
+
+export function UnsupportedFormatDialog({
+  open,
+  fileName,
+  fileType,
+  onClose,
+}: UnsupportedFormatDialogProps) {
+  if (!open) return null;
+
+  return (
+    <Modal open={open} onClose={onClose} title="">
+      <div className="p-6 max-w-lg">
+        {/* Header */}
+        <div className="flex items-start justify-between mb-4">
+          <div className="flex items-center gap-3">
+            <FileQuestion className="h-6 w-6 text-yellow-500" />
+            <h2 className="text-lg font-semibold">Unsupported File Format</h2>
+          </div>
+          <button onClick={onClose} className="text-muted-foreground hover:text-foreground">
+            <X className="h-4 w-4" />
+          </button>
+        </div>
+
+        {/* Error Message */}
+        <div className="bg-yellow-500/10 border border-yellow-500/20 rounded-md p-4 mb-4">
+          <div className="flex items-start gap-2">
+            <AlertCircle className="h-4 w-4 text-yellow-600 dark:text-yellow-400 mt-0.5 flex-shrink-0" />
+            <div className="flex-1">
+              <p className="text-sm text-yellow-800 dark:text-yellow-200 font-medium mb-1">
+                Cannot open this file
+              </p>
+              <p className="text-sm text-yellow-700 dark:text-yellow-300">
+                <strong>{fileName}</strong>
+                {fileType && (
+                  <span className="text-muted-foreground"> ({fileType})</span>
+                )}
+              </p>
+            </div>
+          </div>
+        </div>
+
+        {/* Supported Formats */}
+        <div className="mb-6">
+          <h3 className="text-sm font-semibold mb-3">Supported Audio Formats:</h3>
+          <div className="grid grid-cols-1 gap-2">
+            {SUPPORTED_FORMATS.map((format) => (
+              <div
+                key={format.extension}
+                className="flex items-center justify-between gap-4 p-2 rounded bg-muted/30 border border-border/50"
+              >
+                <div className="flex items-center gap-3">
+                  <span className="text-sm font-mono font-semibold text-primary min-w-[80px]">
+                    {format.extension}
+                  </span>
+                  <span className="text-xs text-muted-foreground">
+                    {format.description}
+                  </span>
+                </div>
+              </div>
+            ))}
+          </div>
+        </div>
+
+        {/* Recommendations */}
+        <div className="bg-muted/50 border border-border rounded-md p-4 mb-4">
+          <h4 className="text-sm font-semibold mb-2">How to fix this:</h4>
+          <ul className="text-sm text-muted-foreground space-y-2 list-disc list-inside">
+            <li>Convert your audio file to a supported format (WAV or MP3 recommended)</li>
+            <li>Use a free audio converter like Audacity, FFmpeg, or online converters</li>
+            <li>Check that the file isn't corrupted or incomplete</li>
+          </ul>
+        </div>
+
+        {/* Close Button */}
+        <div className="flex justify-end">
+          <Button onClick={onClose} variant="default">
+            Got it
+          </Button>
+        </div>
+      </div>
+    </Modal>
+  );
+}

components/editor/AudioEditor.tsx

@@ -4,16 +4,9 @@ import * as React from 'react';
 import { Music, Plus, Upload, Trash2, Settings, Download, FolderOpen } from 'lucide-react';
 import { PlaybackControls } from './PlaybackControls';
 import { MasterControls } from '@/components/controls/MasterControls';
-import { FrequencyAnalyzer } from '@/components/analysis/FrequencyAnalyzer';
-import { Spectrogram } from '@/components/analysis/Spectrogram';
-import { PhaseCorrelationMeter } from '@/components/analysis/PhaseCorrelationMeter';
-import { LUFSMeter } from '@/components/analysis/LUFSMeter';
-import { AudioStatistics } from '@/components/analysis/AudioStatistics';
 import { ThemeToggle } from '@/components/layout/ThemeToggle';
 import { CommandPalette } from '@/components/ui/CommandPalette';
-import { GlobalSettingsDialog } from '@/components/settings/GlobalSettingsDialog';
-import { ExportDialog, type ExportSettings } from '@/components/dialogs/ExportDialog';
-import { ProjectsDialog } from '@/components/dialogs/ProjectsDialog';
+import { BrowserCompatDialog } from '@/components/dialogs/BrowserCompatDialog';
 import { Button } from '@/components/ui/Button';
 import type { CommandAction } from '@/components/ui/CommandPalette';
 import { useMultiTrack } from '@/lib/hooks/useMultiTrack';
@@ -21,7 +14,21 @@ import { useMultiTrackPlayer } from '@/lib/hooks/useMultiTrackPlayer';
 import { useEffectChain } from '@/lib/hooks/useEffectChain';
 import { useToast } from '@/components/ui/Toast';
 import { TrackList } from '@/components/tracks/TrackList';
-import { ImportTrackDialog } from '@/components/tracks/ImportTrackDialog';
+import type { ExportSettings } from '@/components/dialogs/ExportDialog';
+
+// Lazy load dialogs for better performance
+const GlobalSettingsDialog = React.lazy(() => import('@/components/settings/GlobalSettingsDialog').then(m => ({ default: m.GlobalSettingsDialog })));
+const ExportDialog = React.lazy(() => import('@/components/dialogs/ExportDialog').then(m => ({ default: m.ExportDialog })));
+const ProjectsDialog = React.lazy(() => import('@/components/dialogs/ProjectsDialog').then(m => ({ default: m.ProjectsDialog })));
+const ImportTrackDialog = React.lazy(() => import('@/components/tracks/ImportTrackDialog').then(m => ({ default: m.ImportTrackDialog })));
+const KeyboardShortcutsDialog = React.lazy(() => import('@/components/dialogs/KeyboardShortcutsDialog').then(m => ({ default: m.KeyboardShortcutsDialog })));
+
+// Lazy load analysis components (shown conditionally based on analyzerView)
+const FrequencyAnalyzer = React.lazy(() => import('@/components/analysis/FrequencyAnalyzer').then(m => ({ default: m.FrequencyAnalyzer })));
+const Spectrogram = React.lazy(() => import('@/components/analysis/Spectrogram').then(m => ({ default: m.Spectrogram })));
+const PhaseCorrelationMeter = React.lazy(() => import('@/components/analysis/PhaseCorrelationMeter').then(m => ({ default: m.PhaseCorrelationMeter })));
+const LUFSMeter = React.lazy(() => import('@/components/analysis/LUFSMeter').then(m => ({ default: m.LUFSMeter })));
+const AudioStatistics = React.lazy(() => import('@/components/analysis/AudioStatistics').then(m => ({ default: m.AudioStatistics })));
 import { formatDuration } from '@/lib/audio/decoder';
 import { useHistory } from '@/lib/hooks/useHistory';
 import { useRecording } from '@/lib/hooks/useRecording';
@@ -48,6 +55,7 @@ import {
   type ProjectMetadata,
 } from '@/lib/storage/projects';
 import { getAudioContext } from '@/lib/audio/context';
+import { checkBrowserCompatibility } from '@/lib/utils/browser-compat';
 
 export function AudioEditor() {
   // Settings hook
@@ -66,6 +74,7 @@ export function AudioEditor() {
   const [masterVolume, setMasterVolume] = React.useState(0.8);
   const [masterPan, setMasterPan] = React.useState(0);
   const [isMasterMuted, setIsMasterMuted] = React.useState(false);
+  const [masterControlsCollapsed, setMasterControlsCollapsed] = React.useState(false);
   const [clipboard, setClipboard] = React.useState<AudioBuffer | null>(null);
   const [recordingTrackId, setRecordingTrackId] = React.useState<string | null>(null);
   const [punchInEnabled, setPunchInEnabled] = React.useState(false);
@@ -87,6 +96,12 @@ export function AudioEditor() {
   const [projects, setProjects] = React.useState<ProjectMetadata[]>([]);
   const [currentProjectId, setCurrentProjectId] = React.useState<string | null>(null);
   const [currentProjectName, setCurrentProjectName] = React.useState('Untitled Project');
+  const [browserCompatDialogOpen, setBrowserCompatDialogOpen] = React.useState(false);
+  const [shortcutsDialogOpen, setShortcutsDialogOpen] = React.useState(false);
+  const [browserCompatInfo, setBrowserCompatInfo] = React.useState<{
+    missingFeatures: string[];
+    warnings: string[];
+  }>({ missingFeatures: [], warnings: [] });
 
   const { addToast } = useToast();
 
@@ -633,6 +648,9 @@ export function AudioEditor() {
     );
     setClipboard(extracted);
 
+    // Ensure the track is selected so paste works
+    setSelectedTrackId(track.id);
+
     // Execute cut command
     const command = createMultiTrackCutCommand(
       track.id,
@@ -664,6 +682,9 @@ export function AudioEditor() {
     );
     setClipboard(extracted);
 
+    // Ensure the track is selected so paste works
+    setSelectedTrackId(track.id);
+
     // Execute copy command (doesn't modify buffer, just for undo history)
     const command = createMultiTrackCopyCommand(
       track.id,
@@ -684,7 +705,25 @@ export function AudioEditor() {
   }, [tracks, executeCommand, updateTrack, addToast]);
 
   const handlePaste = React.useCallback(() => {
-    if (!clipboard || !selectedTrackId) return;
+    if (!clipboard) {
+      addToast({
+        title: 'Nothing to Paste',
+        description: 'Clipboard is empty. Copy or cut a selection first.',
+        variant: 'error',
+        duration: 2000,
+      });
+      return;
+    }
+
+    if (!selectedTrackId) {
+      addToast({
+        title: 'No Track Selected',
+        description: 'Select a track to paste into.',
+        variant: 'error',
+        duration: 2000,
+      });
+      return;
+    }
 
     const track = tracks.find((t) => t.id === selectedTrackId);
     if (!track) return;
@@ -1056,6 +1095,16 @@ export function AudioEditor() {
     }
   }, [loadTracks, addToast]);
 
+  // Check browser compatibility on mount
+  React.useEffect(() => {
+    const { isSupported, missingFeatures, warnings } = checkBrowserCompatibility();
+
+    if (!isSupported || warnings.length > 0) {
+      setBrowserCompatInfo({ missingFeatures, warnings });
+      setBrowserCompatDialogOpen(true);
+    }
+  }, []);
+
   // Auto-load last project on mount
   const [hasAutoLoaded, setHasAutoLoaded] = React.useState(false);
   React.useEffect(() => {
@@ -1266,6 +1315,80 @@ export function AudioEditor() {
         category: 'playback',
         action: stop,
       },
+      // Edit
+      {
+        id: 'undo',
+        label: 'Undo',
+        description: 'Undo last action',
+        shortcut: 'Ctrl+Z',
+        category: 'edit',
+        action: undo,
+      },
+      {
+        id: 'redo',
+        label: 'Redo',
+        description: 'Redo last undone action',
+        shortcut: 'Ctrl+Shift+Z',
+        category: 'edit',
+        action: redo,
+      },
+      {
+        id: 'cut',
+        label: 'Cut',
+        description: 'Cut selection to clipboard',
+        shortcut: 'Ctrl+X',
+        category: 'edit',
+        action: handleCut,
+      },
+      {
+        id: 'copy',
+        label: 'Copy',
+        description: 'Copy selection to clipboard',
+        shortcut: 'Ctrl+C',
+        category: 'edit',
+        action: handleCopy,
+      },
+      {
+        id: 'paste',
+        label: 'Paste',
+        description: 'Paste clipboard content',
+        shortcut: 'Ctrl+V',
+        category: 'edit',
+        action: handlePaste,
+      },
+      {
+        id: 'delete',
+        label: 'Delete',
+        description: 'Delete selection',
+        shortcut: 'Delete',
+        category: 'edit',
+        action: handleDelete,
+      },
+      {
+        id: 'duplicate',
+        label: 'Duplicate',
+        description: 'Duplicate selection',
+        shortcut: 'Ctrl+D',
+        category: 'edit',
+        action: handleDuplicate,
+      },
+      {
+        id: 'select-all',
+        label: 'Select All',
+        description: 'Select all content on current track',
+        shortcut: 'Ctrl+A',
+        category: 'edit',
+        action: () => {
+          if (selectedTrackId) {
+            const track = tracks.find(t => t.id === selectedTrackId);
+            if (track?.audioBuffer) {
+              updateTrack(selectedTrackId, {
+                selection: { start: 0, end: track.audioBuffer.duration }
+              });
+            }
+          }
+        },
+      },
       // Project
       {
         id: 'save-project',
@@ -1287,6 +1410,7 @@ export function AudioEditor() {
         id: 'zoom-in',
         label: 'Zoom In',
         description: 'Zoom in on waveforms',
+        shortcut: 'Ctrl++',
         category: 'view',
         action: handleZoomIn,
       },
@@ -1294,6 +1418,7 @@ export function AudioEditor() {
         id: 'zoom-out',
         label: 'Zoom Out',
         description: 'Zoom out on waveforms',
+        shortcut: 'Ctrl+-',
         category: 'view',
         action: handleZoomOut,
       },
@@ -1301,9 +1426,59 @@ export function AudioEditor() {
         id: 'fit-to-view',
         label: 'Fit to View',
         description: 'Reset zoom to fit all tracks',
+        shortcut: 'Ctrl+0',
         category: 'view',
         action: handleFitToView,
       },
+      // Navigation
+      {
+        id: 'seek-start',
+        label: 'Go to Start',
+        description: 'Seek to beginning',
+        shortcut: 'Home',
+        category: 'playback',
+        action: () => seek(0),
+      },
+      {
+        id: 'seek-end',
+        label: 'Go to End',
+        description: 'Seek to end',
+        shortcut: 'End',
+        category: 'playback',
+        action: () => seek(duration),
+      },
+      {
+        id: 'seek-backward',
+        label: 'Seek Backward',
+        description: 'Seek backward 1 second',
+        shortcut: '←',
+        category: 'playback',
+        action: () => seek(Math.max(0, currentTime - 1)),
+      },
+      {
+        id: 'seek-forward',
+        label: 'Seek Forward',
+        description: 'Seek forward 1 second',
+        shortcut: '→',
+        category: 'playback',
+        action: () => seek(Math.min(duration, currentTime + 1)),
+      },
+      {
+        id: 'seek-backward-5s',
+        label: 'Seek Backward 5s',
+        description: 'Seek backward 5 seconds',
+        shortcut: 'Ctrl+←',
+        category: 'playback',
+        action: () => seek(Math.max(0, currentTime - 5)),
+      },
+      {
+        id: 'seek-forward-5s',
+        label: 'Seek Forward 5s',
+        description: 'Seek forward 5 seconds',
+        shortcut: 'Ctrl+→',
+        category: 'playback',
+        action: () => seek(Math.min(duration, currentTime + 5)),
+      },
       // Tracks
       {
         id: 'add-track',
@@ -1326,9 +1501,18 @@ export function AudioEditor() {
         category: 'tracks',
         action: handleClearTracks,
       },
+      // Help
+      {
+        id: 'keyboard-shortcuts',
+        label: 'Keyboard Shortcuts',
+        description: 'View all keyboard shortcuts',
+        shortcut: '?',
+        category: 'view',
+        action: () => setShortcutsDialogOpen(true),
+      },
     ];
     return actions;
-  }, [play, pause, stop, handleSaveProject, handleOpenProjectsDialog, handleZoomIn, handleZoomOut, handleFitToView, handleImportTracks, handleClearTracks, addTrack]);
+  }, [play, pause, stop, undo, redo, handleCut, handleCopy, handlePaste, handleDelete, handleDuplicate, handleSaveProject, handleOpenProjectsDialog, handleZoomIn, handleZoomOut, handleFitToView, handleImportTracks, handleClearTracks, addTrack, seek, duration, currentTime, selectedTrackId, tracks, updateTrack, setShortcutsDialogOpen]);
 
   // Keyboard shortcuts
   React.useEffect(() => {
@@ -1398,6 +1582,27 @@ export function AudioEditor() {
         return;
       }
 
+      // Ctrl/Cmd++: Zoom In (also accepts Ctrl+=)
+      if ((e.ctrlKey || e.metaKey) && (e.key === '=' || e.key === '+')) {
+        e.preventDefault();
+        handleZoomIn();
+        return;
+      }
+
+      // Ctrl/Cmd+-: Zoom Out
+      if ((e.ctrlKey || e.metaKey) && e.key === '-') {
+        e.preventDefault();
+        handleZoomOut();
+        return;
+      }
+
+      // Ctrl/Cmd+0: Fit to View
+      if ((e.ctrlKey || e.metaKey) && e.key === '0') {
+        e.preventDefault();
+        handleFitToView();
+        return;
+      }
+
       // Delete or Backspace: Delete selection
       if (e.key === 'Delete' || e.key === 'Backspace') {
         e.preventDefault();
@@ -1457,7 +1662,16 @@ export function AudioEditor() {
       // Ctrl+A: Select All (select all content on current track)
       if ((e.ctrlKey || e.metaKey) && e.key === 'a') {
         e.preventDefault();
-        if (selectedTrackId) {
+        if (!selectedTrackId) {
+          // If no track selected, try to select the first track with audio
+          const trackWithAudio = tracks.find(t => t.audioBuffer);
+          if (trackWithAudio && trackWithAudio.audioBuffer) {
+            setSelectedTrackId(trackWithAudio.id);
+            updateTrack(trackWithAudio.id, {
+              selection: { start: 0, end: trackWithAudio.audioBuffer.duration }
+            });
+          }
+        } else {
           const track = tracks.find(t => t.id === selectedTrackId);
           if (track?.audioBuffer) {
             updateTrack(selectedTrackId, {
@@ -1468,45 +1682,31 @@ export function AudioEditor() {
         return;
       }
 
-      // Ctrl+Plus/Equals: Zoom in
-      if ((e.ctrlKey || e.metaKey) && (e.key === '+' || e.key === '=')) {
+      // ?: Open keyboard shortcuts help
+      if (e.key === '?' && !e.ctrlKey && !e.metaKey) {
         e.preventDefault();
-        handleZoomIn();
-        return;
-      }
-
-      // Ctrl+Minus: Zoom out
-      if ((e.ctrlKey || e.metaKey) && e.key === '-') {
-        e.preventDefault();
-        handleZoomOut();
-        return;
-      }
-
-      // Ctrl+0: Fit to view
-      if ((e.ctrlKey || e.metaKey) && e.key === '0') {
-        e.preventDefault();
-        handleFitToView();
+        setShortcutsDialogOpen(true);
         return;
       }
     };
 
     window.addEventListener('keydown', handleKeyDown);
     return () => window.removeEventListener('keydown', handleKeyDown);
-  }, [togglePlayPause, canUndo, canRedo, undo, redo, handleCut, handleCopy, handlePaste, handleDelete, handleDuplicate, handleSaveProject, seek, duration, currentTime, selectedTrackId, tracks, updateTrack, handleZoomIn, handleZoomOut, handleFitToView]);
+  }, [togglePlayPause, canUndo, canRedo, undo, redo, handleCut, handleCopy, handlePaste, handleDelete, handleDuplicate, handleSaveProject, seek, duration, currentTime, selectedTrackId, tracks, updateTrack, handleZoomIn, handleZoomOut, handleFitToView, setSelectedTrackId, setShortcutsDialogOpen]);
 
   return (
     <>
       {/* Compact Header */}
-      <header className="flex items-center justify-between px-4 py-2 border-b border-border bg-card flex-shrink-0 gap-4">
+      <header className="flex items-center justify-between px-2 sm:px-4 py-2 border-b border-border bg-card flex-shrink-0 gap-2 sm:gap-4">
         {/* Left: Logo */}
-        <div className="flex items-center gap-4 flex-shrink-0">
+        <div className="flex items-center gap-2 sm:gap-4 flex-shrink-0">
           <div className="flex items-center gap-2">
             <Music className="h-5 w-5 text-primary" />
-            <h1 className="text-lg font-bold text-foreground">Audio UI</h1>
+            <h1 className="text-base sm:text-lg font-bold text-foreground hidden sm:block">Audio UI</h1>
           </div>
 
           {/* Project Name */}
-          <div className="flex items-center gap-2 border-l border-border pl-4">
+          <div className="hidden md:flex items-center gap-2 border-l border-border pl-4">
             <input
               type="text"
               value={currentProjectName}
@@ -1518,27 +1718,31 @@ export function AudioEditor() {
             />
           </div>
 
-          {/* Track Actions */}
-          <div className="flex items-center gap-2 border-l border-border pl-4">
-            <Button variant="outline" size="sm" onClick={handleOpenProjectsDialog}>
+          {/* Track Actions - Compact on mobile */}
+          <div className="flex items-center gap-1 sm:gap-2 border-l border-border pl-2 sm:pl-4">
+            <Button variant="outline" size="sm" onClick={handleOpenProjectsDialog} className="hidden sm:flex">
               <FolderOpen className="h-4 w-4 mr-1.5" />
               Projects
             </Button>
+            <Button variant="outline" size="sm" onClick={handleOpenProjectsDialog} className="sm:hidden px-2">
+              <FolderOpen className="h-4 w-4" />
+            </Button>
+
             <Button variant="outline" size="sm" onClick={() => addTrack()}>
-              <Plus className="h-4 w-4 mr-1.5" />
-              Add Track
+              <Plus className="h-4 w-4 sm:mr-1.5" />
+              <span className="hidden sm:inline">Add Track</span>
             </Button>
             <Button variant="outline" size="sm" onClick={handleImportTracks}>
-              <Upload className="h-4 w-4 mr-1.5" />
-              Import
+              <Upload className="h-4 w-4 sm:mr-1.5" />
+              <span className="hidden sm:inline">Import</span>
             </Button>
             {tracks.length > 0 && (
               <>
-                <Button variant="outline" size="sm" onClick={() => setExportDialogOpen(true)}>
+                <Button variant="outline" size="sm" onClick={() => setExportDialogOpen(true)} className="hidden md:flex">
                   <Download className="h-4 w-4 mr-1.5" />
                   Export
                 </Button>
-                <Button variant="outline" size="sm" onClick={handleClearTracks}>
+                <Button variant="outline" size="sm" onClick={handleClearTracks} className="hidden lg:flex">
                   <Trash2 className="h-4 w-4 mr-1.5 text-destructive" />
                   Clear All
                 </Button>
@@ -1591,8 +1795,8 @@ export function AudioEditor() {
           </div>
         </main>
 
-        {/* Right Sidebar - Master Controls & Analyzers */}
-        <aside className="flex-shrink-0 border-l border-border bg-card flex flex-col pt-5 px-4 pb-4 gap-4 w-60">
+        {/* Right Sidebar - Master Controls & Analyzers - Hidden on mobile */}
+        <aside className="hidden lg:flex flex-shrink-0 border-l border-border bg-card flex-col pt-5 px-4 pb-4 gap-4 w-60">
           {/* Master Controls */}
           <div className="flex items-center justify-center">
             <MasterControls
@@ -1602,6 +1806,7 @@ export function AudioEditor() {
               rmsLevel={masterRmsLevel}
               isClipping={masterIsClipping}
               isMuted={isMasterMuted}
+              collapsed={masterControlsCollapsed}
               onVolumeChange={setMasterVolume}
               onPanChange={setMasterPan}
               onMuteToggle={() => {
@@ -1614,6 +1819,7 @@ export function AudioEditor() {
                 }
               }}
               onResetClip={resetClipIndicator}
+              onToggleCollapse={() => setMasterControlsCollapsed(!masterControlsCollapsed)}
             />
           </div>
 
@@ -1681,18 +1887,66 @@ export function AudioEditor() {
           {/* Analyzer Display */}
           <div className="flex-1 min-h-[360px] flex items-start justify-center">
             <div className="w-[178px]">
-              {analyzerView === 'frequency' && <FrequencyAnalyzer analyserNode={masterAnalyser} />}
-              {analyzerView === 'spectrogram' && settings.performance.enableSpectrogram && <Spectrogram analyserNode={masterAnalyser} />}
-              {analyzerView === 'phase' && <PhaseCorrelationMeter analyserNode={masterAnalyser} />}
-              {analyzerView === 'lufs' && <LUFSMeter analyserNode={masterAnalyser} />}
-              {analyzerView === 'stats' && <AudioStatistics tracks={tracks} />}
+              {analyzerView === 'frequency' && (
+                <React.Suspense fallback={<div className="h-[300px] flex items-center justify-center text-muted-foreground">Loading...</div>}>
+                  <FrequencyAnalyzer analyserNode={masterAnalyser} />
+                </React.Suspense>
+              )}
+              {analyzerView === 'spectrogram' && settings.performance.enableSpectrogram && (
+                <React.Suspense fallback={<div className="h-[300px] flex items-center justify-center text-muted-foreground">Loading...</div>}>
+                  <Spectrogram analyserNode={masterAnalyser} />
+                </React.Suspense>
+              )}
+              {analyzerView === 'phase' && (
+                <React.Suspense fallback={<div className="h-[300px] flex items-center justify-center text-muted-foreground">Loading...</div>}>
+                  <PhaseCorrelationMeter analyserNode={masterAnalyser} />
+                </React.Suspense>
+              )}
+              {analyzerView === 'lufs' && (
+                <React.Suspense fallback={<div className="h-[300px] flex items-center justify-center text-muted-foreground">Loading...</div>}>
+                  <LUFSMeter analyserNode={masterAnalyser} />
+                </React.Suspense>
+              )}
+              {analyzerView === 'stats' && (
+                <React.Suspense fallback={<div className="h-[300px] flex items-center justify-center text-muted-foreground">Loading...</div>}>
+                  <AudioStatistics tracks={tracks} />
+                </React.Suspense>
+              )}
             </div>
           </div>
         </aside>
       </div>
 
-      {/* Transport Controls */}
-      <div className="border-t border-border bg-card p-3 flex justify-center">
+      {/* Bottom Bar - Stacked on mobile (Master then Transport), Side-by-side on desktop */}
+      <div className="border-t border-border bg-card p-3 flex flex-col lg:flex-row gap-3">
+        {/* Master Controls - Mobile only (hidden on desktop where sidebar shows master) */}
+        <div className="lg:hidden flex justify-center border-b border-border pb-3 lg:border-b-0 lg:pb-0">
+          <MasterControls
+            volume={masterVolume}
+            pan={masterPan}
+            peakLevel={masterPeakLevel}
+            rmsLevel={masterRmsLevel}
+            isClipping={masterIsClipping}
+            isMuted={isMasterMuted}
+            collapsed={masterControlsCollapsed}
+            onVolumeChange={setMasterVolume}
+            onPanChange={setMasterPan}
+            onMuteToggle={() => {
+              if (isMasterMuted) {
+                setMasterVolume(0.8);
+                setIsMasterMuted(false);
+              } else {
+                setMasterVolume(0);
+                setIsMasterMuted(true);
+              }
+            }}
+            onResetClip={resetClipIndicator}
+            onToggleCollapse={() => setMasterControlsCollapsed(!masterControlsCollapsed)}
+          />
+        </div>
+
+        {/* Playback Controls - Bottom on mobile, centered on desktop */}
+        <div className="flex-1 flex justify-center">
           <PlaybackControls
             isPlaying={isPlaying}
             isPaused={!isPlaying}
@@ -1719,15 +1973,19 @@ export function AudioEditor() {
             onOverdubEnabledChange={setOverdubEnabled}
           />
         </div>
+      </div>
 
       {/* Import Track Dialog */}
+      <React.Suspense fallback={null}>
         <ImportTrackDialog
           open={importDialogOpen}
           onClose={() => setImportDialogOpen(false)}
           onImportTrack={handleImportTrack}
         />
+      </React.Suspense>
 
       {/* Global Settings Dialog */}
+      <React.Suspense fallback={null}>
         <GlobalSettingsDialog
           open={settingsDialogOpen}
           onClose={() => setSettingsDialogOpen(false)}
@@ -1742,8 +2000,10 @@ export function AudioEditor() {
           onPerformanceSettingsChange={updatePerformanceSettings}
           onResetCategory={resetCategory}
         />
+      </React.Suspense>
 
       {/* Export Dialog */}
+      <React.Suspense fallback={null}>
         <ExportDialog
           open={exportDialogOpen}
           onClose={() => setExportDialogOpen(false)}
@@ -1751,8 +2011,10 @@ export function AudioEditor() {
           isExporting={isExporting}
           hasSelection={tracks.some(t => t.selection !== null)}
         />
+      </React.Suspense>
 
       {/* Projects Dialog */}
+      <React.Suspense fallback={null}>
         <ProjectsDialog
           open={projectsDialogOpen}
           onClose={() => setProjectsDialogOpen(false)}
@@ -1764,6 +2026,23 @@ export function AudioEditor() {
           onExportProject={handleExportProject}
           onImportProject={handleImportProject}
         />
+      </React.Suspense>
+
+      {/* Browser Compatibility Dialog */}
+      <BrowserCompatDialog
+        open={browserCompatDialogOpen}
+        missingFeatures={browserCompatInfo.missingFeatures}
+        warnings={browserCompatInfo.warnings}
+        onClose={() => setBrowserCompatDialogOpen(false)}
+      />
+
+      {/* Keyboard Shortcuts Dialog */}
+      <React.Suspense fallback={null}>
+        <KeyboardShortcutsDialog
+          open={shortcutsDialogOpen}
+          onClose={() => setShortcutsDialogOpen(false)}
+        />
+      </React.Suspense>
     </>
   );
 }

components/tracks/Track.tsx

@@ -21,6 +21,7 @@ import {
   COLLAPSED_TRACK_HEIGHT,
   MIN_TRACK_HEIGHT,
   MAX_TRACK_HEIGHT,
+  DEFAULT_TRACK_HEIGHT,
 } from "@/types/track";
 import { Button } from "@/components/ui/Button";
 import { Slider } from "@/components/ui/Slider";
@@ -606,7 +607,9 @@ export function Track({
     }
   };
 
-  const trackHeight = track.collapsed ? COLLAPSED_TRACK_HEIGHT : Math.max(track.height || MIN_TRACK_HEIGHT, MIN_TRACK_HEIGHT);
+  const trackHeight = track.collapsed
+    ? COLLAPSED_TRACK_HEIGHT
+    : Math.max(track.height || DEFAULT_TRACK_HEIGHT, MIN_TRACK_HEIGHT);
 
   // Track height resize handlers
   const handleResizeStart = React.useCallback(
@@ -656,7 +659,9 @@ export function Track({
               ? "bg-primary/10 border-r-primary"
               : "bg-card border-r-transparent hover:bg-accent/30",
           )}
-          style={{ height: trackHeight }}
+          style={{
+            height: `${trackHeight}px`,
+          }}
           onClick={(e) => {
             e.stopPropagation();
             if (onSelect) onSelect();

components/tracks/TrackControls.tsx

@@ -1,7 +1,7 @@
 'use client';
 
 import * as React from 'react';
-import { Circle, Headphones, MoreHorizontal, ChevronRight, ChevronDown } from 'lucide-react';
+import { Circle, Headphones, MoreHorizontal, ChevronRight, ChevronDown, ChevronUp } from 'lucide-react';
 import { CircularKnob } from '@/components/ui/CircularKnob';
 import { TrackFader } from './TrackFader';
 import { cn } from '@/lib/utils/cn';
@@ -20,6 +20,7 @@ export interface TrackControlsProps {
   showAutomation?: boolean;
   showEffects?: boolean;
   isRecording?: boolean;
+  mobileCollapsed?: boolean; // For mobile view collapsible controls
   onNameChange: (name: string) => void;
   onToggleCollapse: () => void;
   onVolumeChange: (volume: number) => void;
@@ -33,6 +34,7 @@ export interface TrackControlsProps {
   onVolumeTouchEnd?: () => void;
   onPanTouchStart?: () => void;
   onPanTouchEnd?: () => void;
+  onToggleMobileCollapse?: () => void;
   className?: string;
 }
 
@@ -50,6 +52,7 @@ export function TrackControls({
   showAutomation = false,
   showEffects = false,
   isRecording = false,
+  mobileCollapsed = false,
   onNameChange,
   onToggleCollapse,
   onVolumeChange,
@@ -63,6 +66,7 @@ export function TrackControls({
   onVolumeTouchEnd,
   onPanTouchStart,
   onPanTouchEnd,
+  onToggleMobileCollapse,
   className,
 }: TrackControlsProps) {
   const [isEditingName, setIsEditingName] = React.useState(false);
@@ -91,9 +95,236 @@ export function TrackControls({
     }
   };
 
+  // Mobile collapsed view - minimal controls (like master controls)
+  if (mobileCollapsed) {
     return (
       <div className={cn(
-      'flex flex-col items-center gap-3 px-4 py-3 bg-card/50 border-2 border-accent/50 rounded-lg',
+        'flex flex-col items-center gap-2 px-3 py-2 bg-card/50 border border-accent/50 rounded-lg w-full sm:hidden',
+        className
+      )}>
+        <div className="flex items-center justify-between w-full">
+          <div className="flex items-center gap-1 flex-1">
+            <button
+              onClick={onToggleCollapse}
+              className="p-0.5 hover:bg-accent/20 rounded transition-colors flex-shrink-0"
+              title={collapsed ? 'Expand track' : 'Collapse track'}
+            >
+              {collapsed ? (
+                <ChevronRight className="h-3 w-3 text-muted-foreground" />
+              ) : (
+                <ChevronDown className="h-3 w-3 text-muted-foreground" />
+              )}
+            </button>
+            <div
+              className="text-xs font-bold uppercase tracking-wider"
+              style={{ color: trackColor }}
+            >
+              {trackName}
+            </div>
+          </div>
+          {onToggleMobileCollapse && (
+            <button
+              onClick={onToggleMobileCollapse}
+              className="p-1 hover:bg-accent/20 rounded transition-colors"
+              title="Expand track controls"
+            >
+              <ChevronDown className="h-3 w-3 text-muted-foreground" />
+            </button>
+          )}
+        </div>
+        <div className="flex items-center gap-1 w-full justify-center">
+          {onRecordToggle && (
+            <button
+              onClick={onRecordToggle}
+              className={cn(
+                'h-7 w-7 rounded-full flex items-center justify-center transition-all',
+                isRecordEnabled
+                  ? isRecording
+                    ? 'bg-red-500 shadow-lg shadow-red-500/50 animate-pulse'
+                    : 'bg-red-500 shadow-md shadow-red-500/30'
+                  : 'bg-card hover:bg-accent border border-border/50'
+              )}
+              title={isRecordEnabled ? 'Record Armed' : 'Arm for Recording'}
+            >
+              <Circle className={cn('h-3.5 w-3.5', isRecordEnabled ? 'fill-white text-white' : 'text-muted-foreground')} />
+            </button>
+          )}
+          <button
+            onClick={onMuteToggle}
+            className={cn(
+              'h-7 w-7 rounded-md flex items-center justify-center transition-all text-xs font-bold',
+              isMuted
+                ? 'bg-blue-500 text-white shadow-md shadow-blue-500/30'
+                : 'bg-card hover:bg-accent text-muted-foreground border border-border/50'
+            )}
+            title={isMuted ? 'Unmute' : 'Mute'}
+          >
+            M
+          </button>
+          {onSoloToggle && (
+            <button
+              onClick={onSoloToggle}
+              className={cn(
+                'h-7 w-7 rounded-md flex items-center justify-center transition-all text-xs font-bold',
+                isSolo
+                  ? 'bg-yellow-500 text-white shadow-md shadow-yellow-500/30'
+                  : 'bg-card hover:bg-accent text-muted-foreground border border-border/50'
+              )}
+              title={isSolo ? 'Unsolo' : 'Solo'}
+            >
+              S
+            </button>
+          )}
+          <div className="flex-1 h-2 bg-muted rounded-full overflow-hidden">
+            <div
+              className={cn(
+                'h-full transition-all',
+                peakLevel > 0.95 ? 'bg-red-500' : peakLevel > 0.8 ? 'bg-yellow-500' : 'bg-green-500'
+              )}
+              style={{ width: `${peakLevel * 100}%` }}
+            />
+          </div>
+        </div>
+      </div>
+    );
+  }
+
+  // Mobile expanded view - full controls (like master controls)
+  const mobileExpandedView = (
+    <div className={cn(
+      'flex flex-col items-center gap-3 px-3 py-3 bg-card/50 border border-accent/50 rounded-lg w-full sm:hidden',
+      className
+    )}>
+      {/* Header with collapse button */}
+      <div className="flex items-center justify-between w-full">
+        <button
+          onClick={onToggleCollapse}
+          className="p-0.5 hover:bg-accent/20 rounded transition-colors flex-shrink-0"
+          title={collapsed ? 'Expand track' : 'Collapse track'}
+        >
+          {collapsed ? (
+            <ChevronRight className="h-3 w-3 text-muted-foreground" />
+          ) : (
+            <ChevronDown className="h-3 w-3 text-muted-foreground" />
+          )}
+        </button>
+        <div
+          className="text-xs font-bold uppercase tracking-wider flex-1 text-center"
+          style={{ color: trackColor }}
+        >
+          {trackName}
+        </div>
+        {onToggleMobileCollapse && (
+          <button
+            onClick={onToggleMobileCollapse}
+            className="p-0.5 hover:bg-accent/20 rounded transition-colors flex-shrink-0"
+            title="Collapse track controls"
+          >
+            <ChevronUp className="h-3 w-3 text-muted-foreground" />
+          </button>
+        )}
+      </div>
+
+      {/* Pan Control */}
+      <CircularKnob
+        value={pan}
+        onChange={onPanChange}
+        onTouchStart={onPanTouchStart}
+        onTouchEnd={onPanTouchEnd}
+        min={-1}
+        max={1}
+        step={0.01}
+        label="PAN"
+        size={48}
+        formatValue={(value: number) => {
+          if (Math.abs(value) < 0.01) return 'C';
+          if (value < 0) return `${Math.abs(value * 100).toFixed(0)}L`;
+          return `${(value * 100).toFixed(0)}R`;
+        }}
+      />
+
+      {/* Volume Fader - Full height, not compressed */}
+      <div className="flex-1 flex justify-center items-center w-full min-h-[160px]">
+        <TrackFader
+          value={volume}
+          peakLevel={peakLevel}
+          rmsLevel={rmsLevel}
+          onChange={onVolumeChange}
+          onTouchStart={onVolumeTouchStart}
+          onTouchEnd={onVolumeTouchEnd}
+        />
+      </div>
+
+      {/* Control buttons */}
+      <div className="flex items-center gap-1 w-full justify-center">
+        {onRecordToggle && (
+          <button
+            onClick={onRecordToggle}
+            className={cn(
+              'h-8 w-8 rounded-full flex items-center justify-center transition-all',
+              isRecordEnabled
+                ? isRecording
+                  ? 'bg-red-500 shadow-lg shadow-red-500/50 animate-pulse'
+                  : 'bg-red-500 shadow-md shadow-red-500/30'
+                : 'bg-card hover:bg-accent border border-border/50'
+            )}
+            title={isRecordEnabled ? 'Record Armed' : 'Arm for Recording'}
+          >
+            <Circle className={cn('h-3.5 w-3.5', isRecordEnabled ? 'fill-white text-white' : 'text-muted-foreground')} />
+          </button>
+        )}
+        <button
+          onClick={onMuteToggle}
+          className={cn(
+            'h-8 w-8 rounded-md flex items-center justify-center transition-all text-xs font-bold',
+            isMuted
+              ? 'bg-blue-500 text-white shadow-md shadow-blue-500/30'
+              : 'bg-card hover:bg-accent text-muted-foreground border border-border/50'
+          )}
+          title={isMuted ? 'Unmute' : 'Mute'}
+        >
+          M
+        </button>
+        {onSoloToggle && (
+          <button
+            onClick={onSoloToggle}
+            className={cn(
+              'h-8 w-8 rounded-md flex items-center justify-center transition-all text-xs font-bold',
+              isSolo
+                ? 'bg-yellow-500 text-white shadow-md shadow-yellow-500/30'
+                : 'bg-card hover:bg-accent text-muted-foreground border border-border/50'
+            )}
+            title={isSolo ? 'Unsolo' : 'Solo'}
+          >
+            S
+          </button>
+        )}
+        {onEffectsClick && (
+          <button
+            onClick={onEffectsClick}
+            className={cn(
+              'h-8 w-8 rounded-md flex items-center justify-center transition-all text-xs font-bold',
+              showEffects
+                ? 'bg-purple-500 text-white shadow-md shadow-purple-500/30'
+                : 'bg-card hover:bg-accent text-muted-foreground border border-border/50'
+            )}
+            title="Effects"
+          >
+            FX
+          </button>
+        )}
+      </div>
+    </div>
+  );
+
+  return (
+    <>
+      {/* Mobile view - Show expanded or collapsed */}
+      {!mobileCollapsed && mobileExpandedView}
+
+      {/* Desktop/tablet view - hidden on mobile */}
+      <div className={cn(
+        'flex flex-col items-center gap-3 px-4 py-3 bg-card/50 border border-accent/50 rounded-lg hidden sm:flex',
         className
       )}>
       {/* Track Name Header with Collapse Chevron */}
@@ -221,5 +452,6 @@ export function TrackControls({
         </div>
       </div>
       </div>
+    </>
   );
 }

components/tracks/TrackList.tsx

@@ -167,8 +167,509 @@ export function TrackList({
 
   return (
     <div className="flex-1 flex flex-col overflow-hidden">
-      {/* Track List - Two Column Layout */}
-      <div className="flex-1 flex overflow-hidden">
+      {/* Mobile Layout - Single Column (Stacked: Controls → Waveform per track) */}
+      <div className="flex-1 flex flex-col overflow-y-auto overflow-x-hidden custom-scrollbar lg:hidden">
+        {tracks.map((track) => (
+          <div key={track.id} className="flex flex-col border-b border-border">
+            {/* Track Controls - Top */}
+            <Track
+              track={track}
+              zoom={zoom}
+              currentTime={currentTime}
+              duration={duration}
+              isSelected={selectedTrackId === track.id}
+              onSelect={onSelectTrack ? () => onSelectTrack(track.id) : undefined}
+              onToggleMute={() => onUpdateTrack(track.id, { mute: !track.mute })}
+              onToggleSolo={() => onUpdateTrack(track.id, { solo: !track.solo })}
+              onToggleCollapse={() => onUpdateTrack(track.id, { collapsed: !track.collapsed })}
+              onVolumeChange={(volume) => onUpdateTrack(track.id, { volume })}
+              onPanChange={(pan) => onUpdateTrack(track.id, { pan })}
+              onRemove={() => onRemoveTrack(track.id)}
+              onNameChange={(name) => onUpdateTrack(track.id, { name })}
+              onUpdateTrack={onUpdateTrack}
+              onSeek={onSeek}
+              onLoadAudio={(buffer) => onUpdateTrack(track.id, { audioBuffer: buffer })}
+              onToggleEffect={(effectId) => {
+                const updatedChain = {
+                  ...track.effectChain,
+                  effects: track.effectChain.effects.map((e) =>
+                    e.id === effectId ? { ...e, enabled: !e.enabled } : e
+                  ),
+                };
+                onUpdateTrack(track.id, { effectChain: updatedChain });
+              }}
+              onRemoveEffect={(effectId) => {
+                const updatedChain = {
+                  ...track.effectChain,
+                  effects: track.effectChain.effects.filter((e) => e.id !== effectId),
+                };
+                onUpdateTrack(track.id, { effectChain: updatedChain });
+              }}
+              onUpdateEffect={(effectId, parameters) => {
+                const updatedChain = {
+                  ...track.effectChain,
+                  effects: track.effectChain.effects.map((e) =>
+                    e.id === effectId ? { ...e, parameters } : e
+                  ),
+                };
+                onUpdateTrack(track.id, { effectChain: updatedChain });
+              }}
+              onAddEffect={(effectType) => {
+                const newEffect = createEffect(effectType, EFFECT_NAMES[effectType]);
+                const updatedChain = {
+                  ...track.effectChain,
+                  effects: [...track.effectChain.effects, newEffect],
+                };
+                onUpdateTrack(track.id, { effectChain: updatedChain });
+              }}
+              onSelectionChange={
+                onSelectionChange
+                  ? (selection) => onSelectionChange(track.id, selection)
+                  : undefined
+              }
+              onToggleRecordEnable={
+                onToggleRecordEnable
+                  ? () => onToggleRecordEnable(track.id)
+                  : undefined
+              }
+              isRecording={recordingTrackId === track.id}
+              recordingLevel={recordingTrackId === track.id ? recordingLevel : 0}
+              playbackLevel={trackLevels[track.id] || 0}
+              onParameterTouched={onParameterTouched}
+              isPlaying={isPlaying}
+              renderControlsOnly={true}
+            />
+
+            {/* Track Waveform with Automation and Effects - Bottom */}
+            {!track.collapsed && (
+              <div className="flex flex-col">
+                {/* Waveform */}
+                <div className="min-h-[200px] overflow-x-auto custom-scrollbar">
+                  <Track
+                    track={track}
+                    zoom={zoom}
+                    currentTime={currentTime}
+                    duration={duration}
+                    isSelected={selectedTrackId === track.id}
+                    onSelect={onSelectTrack ? () => onSelectTrack(track.id) : undefined}
+                    onToggleMute={() => onUpdateTrack(track.id, { mute: !track.mute })}
+                    onToggleSolo={() => onUpdateTrack(track.id, { solo: !track.solo })}
+                    onToggleCollapse={() => onUpdateTrack(track.id, { collapsed: !track.collapsed })}
+                    onVolumeChange={(volume) => onUpdateTrack(track.id, { volume })}
+                    onPanChange={(pan) => onUpdateTrack(track.id, { pan })}
+                    onRemove={() => onRemoveTrack(track.id)}
+                    onNameChange={(name) => onUpdateTrack(track.id, { name })}
+                    onUpdateTrack={onUpdateTrack}
+                    onSeek={onSeek}
+                    onLoadAudio={(buffer) => onUpdateTrack(track.id, { audioBuffer: buffer })}
+                    onToggleEffect={(effectId) => {
+                      const updatedChain = {
+                        ...track.effectChain,
+                        effects: track.effectChain.effects.map((e) =>
+                          e.id === effectId ? { ...e, enabled: !e.enabled } : e
+                        ),
+                      };
+                      onUpdateTrack(track.id, { effectChain: updatedChain });
+                    }}
+                    onRemoveEffect={(effectId) => {
+                      const updatedChain = {
+                        ...track.effectChain,
+                        effects: track.effectChain.effects.filter((e) => e.id !== effectId),
+                      };
+                      onUpdateTrack(track.id, { effectChain: updatedChain });
+                    }}
+                    onUpdateEffect={(effectId, parameters) => {
+                      const updatedChain = {
+                        ...track.effectChain,
+                        effects: track.effectChain.effects.map((e) =>
+                          e.id === effectId ? { ...e, parameters } : e
+                        ),
+                      };
+                      onUpdateTrack(track.id, { effectChain: updatedChain });
+                    }}
+                    onAddEffect={(effectType) => {
+                      const newEffect = createEffect(effectType, EFFECT_NAMES[effectType]);
+                      const updatedChain = {
+                        ...track.effectChain,
+                        effects: [...track.effectChain.effects, newEffect],
+                      };
+                      onUpdateTrack(track.id, { effectChain: updatedChain });
+                    }}
+                    onSelectionChange={
+                      onSelectionChange
+                        ? (selection) => onSelectionChange(track.id, selection)
+                        : undefined
+                    }
+                    onToggleRecordEnable={
+                      onToggleRecordEnable
+                        ? () => onToggleRecordEnable(track.id)
+                        : undefined
+                    }
+                    isRecording={recordingTrackId === track.id}
+                    recordingLevel={recordingTrackId === track.id ? recordingLevel : 0}
+                    playbackLevel={trackLevels[track.id] || 0}
+                    onParameterTouched={onParameterTouched}
+                    isPlaying={isPlaying}
+                    renderWaveformOnly={true}
+                  />
+                </div>
+
+                {/* Automation Bar */}
+                {(() => {
+                  const selectedParam = track.automation.selectedParameterId || 'volume';
+                  const currentLane = track.automation.lanes.find(
+                    l => l.parameterId === selectedParam
+                  );
+
+                  // Build available parameters list
+                  const availableParameters: Array<{ id: string; name: string }> = [
+                    { id: 'volume', name: 'Volume' },
+                    { id: 'pan', name: 'Pan' },
+                  ];
+
+                  // Add effect parameters
+                  track.effectChain.effects.forEach((effect) => {
+                    if (effect.parameters) {
+                      Object.keys(effect.parameters).forEach((paramKey) => {
+                        const parameterId = `effect.${effect.id}.${paramKey}`;
+                        const paramName = `${effect.name} - ${paramKey.charAt(0).toUpperCase() + paramKey.slice(1)}`;
+                        availableParameters.push({ id: parameterId, name: paramName });
+                      });
+                    }
+                  });
+
+                  // Get parameters that have automation lanes with points
+                  const automatedParams = track.automation.lanes
+                    .filter(lane => lane.points.length > 0)
+                    .map(lane => {
+                      const param = availableParameters.find(p => p.id === lane.parameterId);
+                      return param ? param.name : lane.parameterName;
+                    });
+
+                  const modes = ['read', 'write', 'touch', 'latch'] as const;
+                  const MODE_LABELS = { read: 'R', write: 'W', touch: 'T', latch: 'L' };
+                  const MODE_COLORS = {
+                    read: 'text-muted-foreground',
+                    write: 'text-red-500',
+                    touch: 'text-yellow-500',
+                    latch: 'text-orange-500',
+                  };
+                  const currentModeIndex = modes.indexOf(currentLane?.mode || 'read');
+
+                  return (
+                    <div className="flex-shrink-0 bg-card/90 backdrop-blur-sm">
+                      {/* Automation Header */}
+                      <div className="flex items-center gap-2 px-3 py-1.5 bg-muted border-t border-b border-border/30">
+                        <span className="text-xs font-medium flex-shrink-0">Automation</span>
+
+                        {/* Color indicator */}
+                        {currentLane?.color && (
+                          <div
+                            className="w-1 h-4 rounded-full flex-shrink-0"
+                            style={{ backgroundColor: currentLane.color }}
+                          />
+                        )}
+
+                        {/* Parameter labels - always visible */}
+                        <div className="flex items-center gap-1.5 flex-1 min-w-0 overflow-x-auto">
+                          {automatedParams.map((paramName, index) => (
+                            <span
+                              key={index}
+                              className="text-[10px] px-1.5 py-0.5 rounded whitespace-nowrap flex-shrink-0 bg-primary/10 text-primary border border-primary/20"
+                            >
+                              {paramName}
+                            </span>
+                          ))}
+                        </div>
+
+                        {/* Controls - only visible when expanded */}
+                        {track.automationExpanded && (
+                          <>
+                            {/* Parameter selector */}
+                            {availableParameters && availableParameters.length > 1 && (
+                              <select
+                                value={selectedParam}
+                                onChange={(e) => onUpdateTrack(track.id, {
+                                  automation: { ...track.automation, selectedParameterId: e.target.value },
+                                })}
+                                className="text-xs font-medium text-foreground w-auto min-w-[120px] max-w-[200px] bg-background/50 border border-border/30 rounded px-1.5 py-0.5 hover:bg-background/80 focus:outline-none focus:ring-1 focus:ring-primary flex-shrink-0"
+                              >
+                                {availableParameters.map((param) => (
+                                  <option key={param.id} value={param.id}>
+                                    {param.name}
+                                  </option>
+                                ))}
+                              </select>
+                            )}
+
+                            {/* Automation mode button */}
+                            <Button
+                              variant="ghost"
+                              size="icon-sm"
+                              onClick={() => {
+                                if (currentLane) {
+                                  const nextIndex = (currentModeIndex + 1) % modes.length;
+                                  const updatedLanes = track.automation.lanes.map((l) =>
+                                    l.id === currentLane.id ? { ...l, mode: modes[nextIndex] } : l
+                                  );
+                                  onUpdateTrack(track.id, {
+                                    automation: { ...track.automation, lanes: updatedLanes },
+                                  });
+                                }
+                              }}
+                              title={`Automation mode: ${currentLane?.mode || 'read'} (click to cycle)`}
+                              className={cn('h-5 w-5 text-[10px] font-bold flex-shrink-0', MODE_COLORS[currentLane?.mode || 'read'])}
+                            >
+                              {MODE_LABELS[currentLane?.mode || 'read']}
+                            </Button>
+
+                            {/* Height controls */}
+                            <div className="flex flex-col gap-0 flex-shrink-0">
+                              <Button
+                                variant="ghost"
+                                size="icon-sm"
+                                onClick={() => {
+                                  if (currentLane) {
+                                    const newHeight = Math.max(60, Math.min(200, currentLane.height + 20));
+                                    const updatedLanes = track.automation.lanes.map((l) =>
+                                      l.id === currentLane.id ? { ...l, height: newHeight } : l
+                                    );
+                                    onUpdateTrack(track.id, {
+                                      automation: { ...track.automation, lanes: updatedLanes },
+                                    });
+                                  }
+                                }}
+                                title="Increase lane height"
+                                className="h-3 w-4 p-0"
+                              >
+                                <ChevronUp className="h-2.5 w-2.5" />
+                              </Button>
+                              <Button
+                                variant="ghost"
+                                size="icon-sm"
+                                onClick={() => {
+                                  if (currentLane) {
+                                    const newHeight = Math.max(60, Math.min(200, currentLane.height - 20));
+                                    const updatedLanes = track.automation.lanes.map((l) =>
+                                      l.id === currentLane.id ? { ...l, height: newHeight } : l
+                                    );
+                                    onUpdateTrack(track.id, {
+                                      automation: { ...track.automation, lanes: updatedLanes },
+                                    });
+                                  }
+                                }}
+                                title="Decrease lane height"
+                                className="h-3 w-4 p-0"
+                              >
+                                <ChevronDown className="h-2.5 w-2.5" />
+                              </Button>
+                            </div>
+                          </>
+                        )}
+
+                        {/* Show/hide toggle */}
+                        <Button
+                          variant="ghost"
+                          size="icon-sm"
+                          onClick={() => {
+                            onUpdateTrack(track.id, { automationExpanded: !track.automationExpanded });
+                          }}
+                          title={track.automationExpanded ? 'Hide automation controls' : 'Show automation controls'}
+                          className="h-5 w-5 flex-shrink-0"
+                        >
+                          {track.automationExpanded ? (
+                            <Eye className="h-3 w-3" />
+                          ) : (
+                            <EyeOff className="h-3 w-3 text-muted-foreground" />
+                          )}
+                        </Button>
+                      </div>
+
+                      {/* Automation Lane Content - Shown when expanded */}
+                      {track.automationExpanded && (
+                        <div className="overflow-x-auto custom-scrollbar">
+                          <div
+                            style={{
+                              minWidth: duration && zoom > 1 ? `${duration * zoom * 100}px` : '100%',
+                            }}
+                          >
+                            {track.automation.lanes
+                              .filter((lane) => lane.parameterId === (track.automation.selectedParameterId || 'volume') && lane.visible)
+                              .map((lane) => (
+                                <AutomationLane
+                                  key={lane.id}
+                                  lane={lane}
+                                  zoom={zoom}
+                                  currentTime={currentTime}
+                                  duration={duration}
+                                  onAddPoint={(time, value) => {
+                                    const newPoint = createAutomationPoint({ time, value, curve: 'linear' });
+                                    const updatedLanes = track.automation.lanes.map((l) =>
+                                      l.id === lane.id
+                                        ? { ...l, points: [...l.points, newPoint].sort((a, b) => a.time - b.time) }
+                                        : l
+                                    );
+                                    onUpdateTrack(track.id, {
+                                      automation: { ...track.automation, lanes: updatedLanes },
+                                    });
+                                  }}
+                                  onUpdatePoint={(pointId, updates) => {
+                                    const updatedLanes = track.automation.lanes.map((l) =>
+                                      l.id === lane.id
+                                        ? {
+                                            ...l,
+                                            points: l.points.map((p) =>
+                                              p.id === pointId ? { ...p, ...updates } : p
+                                            ),
+                                          }
+                                        : l
+                                    );
+                                    onUpdateTrack(track.id, {
+                                      automation: { ...track.automation, lanes: updatedLanes },
+                                    });
+                                  }}
+                                  onRemovePoint={(pointId) => {
+                                    const updatedLanes = track.automation.lanes.map((l) =>
+                                      l.id === lane.id
+                                        ? { ...l, points: l.points.filter((p) => p.id !== pointId) }
+                                        : l
+                                    );
+                                    onUpdateTrack(track.id, {
+                                      automation: { ...track.automation, lanes: updatedLanes },
+                                    });
+                                  }}
+                                  onUpdateLane={(updates) => {
+                                    const updatedLanes = track.automation.lanes.map((l) =>
+                                      l.id === lane.id ? { ...l, ...updates } : l
+                                    );
+                                    onUpdateTrack(track.id, {
+                                      automation: { ...track.automation, lanes: updatedLanes },
+                                    });
+                                  }}
+                                />
+                              ))}
+                          </div>
+                        </div>
+                      )}
+                    </div>
+                  );
+                })()}
+
+                {/* Effects Bar */}
+                <div className="flex-shrink-0 bg-card/90 backdrop-blur-sm border-b border-border">
+                  {/* Effects Header */}
+                  <div className="flex items-center gap-2 px-3 py-1.5 bg-muted/50 border-t border-b border-border/30">
+                    <span className="text-xs font-medium flex-shrink-0">Effects</span>
+
+                    {/* Effect name labels */}
+                    <div className="flex items-center gap-1.5 flex-1 min-w-0 overflow-x-auto">
+                      {track.effectChain.effects.map((effect) => (
+                        <span
+                          key={effect.id}
+                          className={cn(
+                            "text-[10px] px-1.5 py-0.5 rounded whitespace-nowrap flex-shrink-0",
+                            effect.enabled
+                              ? "bg-primary/10 text-primary border border-primary/20"
+                              : "bg-muted/30 text-muted-foreground border border-border/30 opacity-60"
+                          )}
+                        >
+                          {effect.name}
+                        </span>
+                      ))}
+                    </div>
+
+                    {/* Add effect button - only visible when expanded */}
+                    {track.effectsExpanded && (
+                      <Button
+                        variant="ghost"
+                        size="icon-sm"
+                        onClick={() => setEffectBrowserTrackId(track.id)}
+                        title="Add effect"
+                        className="h-5 w-5 flex-shrink-0"
+                      >
+                        <Plus className="h-3 w-3" />
+                      </Button>
+                    )}
+
+                    {/* Show/hide toggle */}
+                    <Button
+                      variant="ghost"
+                      size="icon-sm"
+                      onClick={() => {
+                        onUpdateTrack(track.id, { effectsExpanded: !track.effectsExpanded });
+                      }}
+                      title={track.effectsExpanded ? 'Hide effects' : 'Show effects'}
+                      className="h-5 w-5 flex-shrink-0"
+                    >
+                      {track.effectsExpanded ? (
+                        <Eye className="h-3 w-3" />
+                      ) : (
+                        <EyeOff className="h-3 w-3 text-muted-foreground" />
+                      )}
+                    </Button>
+                  </div>
+
+                  {/* Effects Content - Collapsible, horizontally scrollable */}
+                  {track.effectsExpanded && (
+                    <div className="h-48 overflow-x-auto custom-scrollbar bg-muted/70 border-t border-border">
+                      <div className="flex h-full gap-3 p-3">
+                        {track.effectChain.effects.length === 0 ? (
+                          <div className="text-xs text-muted-foreground text-center py-8 w-full">
+                            No effects. Click + to add an effect.
+                          </div>
+                        ) : (
+                          track.effectChain.effects.map((effect) => (
+                            <EffectDevice
+                              key={effect.id}
+                              effect={effect}
+                              onToggleEnabled={() => {
+                                const updatedChain = {
+                                  ...track.effectChain,
+                                  effects: track.effectChain.effects.map((e) =>
+                                    e.id === effect.id ? { ...e, enabled: !e.enabled } : e
+                                  ),
+                                };
+                                onUpdateTrack(track.id, { effectChain: updatedChain });
+                              }}
+                              onRemove={() => {
+                                const updatedChain = {
+                                  ...track.effectChain,
+                                  effects: track.effectChain.effects.filter((e) => e.id !== effect.id),
+                                };
+                                onUpdateTrack(track.id, { effectChain: updatedChain });
+                              }}
+                              onUpdateParameters={(params) => {
+                                const updatedChain = {
+                                  ...track.effectChain,
+                                  effects: track.effectChain.effects.map((e) =>
+                                    e.id === effect.id ? { ...e, parameters: params } : e
+                                  ),
+                                };
+                                onUpdateTrack(track.id, { effectChain: updatedChain });
+                              }}
+                              onToggleExpanded={() => {
+                                const updatedEffects = track.effectChain.effects.map((e) =>
+                                  e.id === effect.id ? { ...e, expanded: !e.expanded } : e
+                                );
+                                onUpdateTrack(track.id, {
+                                  effectChain: { ...track.effectChain, effects: updatedEffects },
+                                });
+                              }}
+                            />
+                          ))
+                        )}
+                      </div>
+                    </div>
+                  )}
+                </div>
+              </div>
+            )}
+          </div>
+        ))}
+      </div>
+
+      {/* Desktop Layout - Two Column Layout */}
+      <div className="flex-1 flex overflow-hidden hidden lg:flex">
         {/* Left Column: Track Controls (Fixed Width, No Scroll - synced with waveforms) */}
         <div ref={controlsScrollRef} className="w-60 flex-shrink-0 overflow-hidden pb-3 border-r border-border">
           {tracks.map((track) => (
@@ -271,14 +772,14 @@ export function TrackList({
           <div className="flex flex-col">
             {tracks.map((track) => (
               <React.Fragment key={track.id}>
-                {/* Track Waveform Row with bars stacked below - Fixed height container */}
+                {/* Track Waveform Row with bars stacked below - Total height matches track controls */}
                 <div
                   className="flex flex-col"
                   style={{
                     height: track.collapsed ? `${COLLAPSED_TRACK_HEIGHT}px` : `${Math.max(track.height || DEFAULT_TRACK_HEIGHT, MIN_TRACK_HEIGHT)}px`
                   }}
                 >
-                  {/* Waveform - Takes remaining space, horizontally scrollable */}
+                  {/* Waveform - Takes remaining space after bars */}
                   <div className="flex-1 min-h-0 relative">
                     {/* Upload hint for empty tracks - stays fixed as overlay */}
                     {!track.audioBuffer && !track.collapsed && (

lib/audio/decoder.ts

@@ -3,6 +3,7 @@
  */
 
 import { getAudioContext } from './context';
+import { checkFileMemoryLimit, type MemoryCheckResult } from '../utils/memory-limits';
 
 export interface ImportOptions {
   convertToMono?: boolean;
@@ -248,6 +249,15 @@ export function isSupportedAudioFormat(file: File): boolean {
          /\.(wav|mp3|ogg|webm|flac|aac|m4a|aiff|aif)$/i.test(file.name);
 }
 
+/**
+ * Check memory requirements for an audio file before decoding
+ * @param file File to check
+ * @returns Memory check result with warning if file is large
+ */
+export function checkAudioFileMemory(file: File): MemoryCheckResult {
+  return checkFileMemoryLimit(file.size);
+}
+
 /**
  * Format duration in seconds to MM:SS format
  */

lib/utils/audio-cleanup.ts

@@ -0,0 +1,149 @@
+/**
+ * Audio cleanup utilities to prevent memory leaks
+ */
+
+/**
+ * Safely disconnect and cleanup an AudioNode
+ */
+export function cleanupAudioNode(node: AudioNode | null | undefined): void {
+  if (!node) return;
+
+  try {
+    node.disconnect();
+  } catch (error) {
+    // Node may already be disconnected, ignore error
+    console.debug('AudioNode cleanup error (expected):', error);
+  }
+}
+
+/**
+ * Cleanup multiple audio nodes
+ */
+export function cleanupAudioNodes(nodes: Array<AudioNode | null | undefined>): void {
+  nodes.forEach(cleanupAudioNode);
+}
+
+/**
+ * Safely stop and cleanup an AudioBufferSourceNode
+ */
+export function cleanupAudioSource(source: AudioBufferSourceNode | null | undefined): void {
+  if (!source) return;
+
+  try {
+    source.stop();
+  } catch (error) {
+    // Source may already be stopped, ignore error
+    console.debug('AudioSource stop error (expected):', error);
+  }
+
+  cleanupAudioNode(source);
+}
+
+/**
+ * Cleanup canvas and release resources
+ */
+export function cleanupCanvas(canvas: HTMLCanvasElement | null | undefined): void {
+  if (!canvas) return;
+
+  const ctx = canvas.getContext('2d');
+  if (ctx) {
+    // Clear the canvas
+    ctx.clearRect(0, 0, canvas.width, canvas.height);
+    // Reset transform
+    ctx.setTransform(1, 0, 0, 1, 0, 0);
+  }
+
+  // Release context (helps with memory)
+  canvas.width = 0;
+  canvas.height = 0;
+}
+
+/**
+ * Cancel animation frame safely
+ */
+export function cleanupAnimationFrame(frameId: number | null | undefined): void {
+  if (frameId !== null && frameId !== undefined) {
+    cancelAnimationFrame(frameId);
+  }
+}
+
+/**
+ * Cleanup media stream tracks
+ */
+export function cleanupMediaStream(stream: MediaStream | null | undefined): void {
+  if (!stream) return;
+
+  stream.getTracks().forEach(track => {
+    track.stop();
+  });
+}
+
+/**
+ * Create a cleanup registry for managing multiple cleanup tasks
+ */
+export class CleanupRegistry {
+  private cleanupTasks: Array<() => void> = [];
+
+  /**
+   * Register a cleanup task
+   */
+  register(cleanup: () => void): void {
+    this.cleanupTasks.push(cleanup);
+  }
+
+  /**
+   * Register an audio node for cleanup
+   */
+  registerAudioNode(node: AudioNode): void {
+    this.register(() => cleanupAudioNode(node));
+  }
+
+  /**
+   * Register an audio source for cleanup
+   */
+  registerAudioSource(source: AudioBufferSourceNode): void {
+    this.register(() => cleanupAudioSource(source));
+  }
+
+  /**
+   * Register a canvas for cleanup
+   */
+  registerCanvas(canvas: HTMLCanvasElement): void {
+    this.register(() => cleanupCanvas(canvas));
+  }
+
+  /**
+   * Register an animation frame for cleanup
+   */
+  registerAnimationFrame(frameId: number): void {
+    this.register(() => cleanupAnimationFrame(frameId));
+  }
+
+  /**
+   * Register a media stream for cleanup
+   */
+  registerMediaStream(stream: MediaStream): void {
+    this.register(() => cleanupMediaStream(stream));
+  }
+
+  /**
+   * Execute all cleanup tasks and clear the registry
+   */
+  cleanup(): void {
+    this.cleanupTasks.forEach(task => {
+      try {
+        task();
+      } catch (error) {
+        console.error('Cleanup task failed:', error);
+      }
+    });
+    this.cleanupTasks = [];
+  }
+
+  /**
+   * Get the number of registered cleanup tasks
+   */
+  get size(): number {
+    return this.cleanupTasks.length;
+  }
+}

lib/utils/browser-compat.ts

@@ -0,0 +1,133 @@
+/**
+ * Browser compatibility checking utilities
+ */
+
+export interface BrowserCompatibility {
+  isSupported: boolean;
+  missingFeatures: string[];
+  warnings: string[];
+}
+
+/**
+ * Check if all required browser features are supported
+ */
+export function checkBrowserCompatibility(): BrowserCompatibility {
+  const missingFeatures: string[] = [];
+  const warnings: string[] = [];
+
+  // Check if running in browser
+  if (typeof window === 'undefined') {
+    return {
+      isSupported: true,
+      missingFeatures: [],
+      warnings: [],
+    };
+  }
+
+  // Check Web Audio API
+  if (!window.AudioContext && !(window as any).webkitAudioContext) {
+    missingFeatures.push('Web Audio API');
+  }
+
+  // Check IndexedDB
+  if (!window.indexedDB) {
+    missingFeatures.push('IndexedDB');
+  }
+
+  // Check localStorage
+  try {
+    localStorage.setItem('test', 'test');
+    localStorage.removeItem('test');
+  } catch (e) {
+    missingFeatures.push('LocalStorage');
+  }
+
+  // Check Canvas API
+  const canvas = document.createElement('canvas');
+  if (!canvas.getContext || !canvas.getContext('2d')) {
+    missingFeatures.push('Canvas API');
+  }
+
+  // Check MediaDevices API (for recording)
+  if (!navigator.mediaDevices || !navigator.mediaDevices.getUserMedia) {
+    warnings.push('Microphone recording not supported (requires HTTPS or localhost)');
+  }
+
+  // Check File API
+  if (!window.File || !window.FileReader || !window.FileList || !window.Blob) {
+    missingFeatures.push('File API');
+  }
+
+  // Check AudioWorklet support (optional)
+  if (window.AudioContext && !AudioContext.prototype.hasOwnProperty('audioWorklet')) {
+    warnings.push('AudioWorklet not supported (some features may have higher latency)');
+  }
+
+  // Check OfflineAudioContext
+  if (!window.OfflineAudioContext && !(window as any).webkitOfflineAudioContext) {
+    missingFeatures.push('OfflineAudioContext (required for audio processing)');
+  }
+
+  return {
+    isSupported: missingFeatures.length === 0,
+    missingFeatures,
+    warnings,
+  };
+}
+
+/**
+ * Get user-friendly browser name
+ */
+export function getBrowserInfo(): { name: string; version: string } {
+  // Check if running in browser
+  if (typeof window === 'undefined' || typeof navigator === 'undefined') {
+    return { name: 'Unknown', version: 'Unknown' };
+  }
+
+  const userAgent = navigator.userAgent;
+  let name = 'Unknown';
+  let version = 'Unknown';
+
+  if (userAgent.indexOf('Chrome') > -1 && userAgent.indexOf('Edg') === -1) {
+    name = 'Chrome';
+    const match = userAgent.match(/Chrome\/(\d+)/);
+    version = match ? match[1] : 'Unknown';
+  } else if (userAgent.indexOf('Edg') > -1) {
+    name = 'Edge';
+    const match = userAgent.match(/Edg\/(\d+)/);
+    version = match ? match[1] : 'Unknown';
+  } else if (userAgent.indexOf('Firefox') > -1) {
+    name = 'Firefox';
+    const match = userAgent.match(/Firefox\/(\d+)/);
+    version = match ? match[1] : 'Unknown';
+  } else if (userAgent.indexOf('Safari') > -1 && userAgent.indexOf('Chrome') === -1) {
+    name = 'Safari';
+    const match = userAgent.match(/Version\/(\d+)/);
+    version = match ? match[1] : 'Unknown';
+  }
+
+  return { name, version };
+}
+
+/**
+ * Check if browser version meets minimum requirements
+ */
+export function checkMinimumVersion(): boolean {
+  const { name, version } = getBrowserInfo();
+  const versionNum = parseInt(version, 10);
+
+  const minimumVersions: Record<string, number> = {
+    Chrome: 90,
+    Edge: 90,
+    Firefox: 88,
+    Safari: 14,
+  };
+
+  const minVersion = minimumVersions[name];
+  if (!minVersion) {
+    // Unknown browser, assume it's ok
+    return true;
+  }
+
+  return versionNum >= minVersion;
+}

lib/utils/memory-limits.ts

@@ -0,0 +1,160 @@
+/**
+ * Memory limit checking utilities for audio file handling
+ */
+
+export interface MemoryCheckResult {
+  allowed: boolean;
+  warning?: string;
+  estimatedMemoryMB: number;
+  availableMemoryMB?: number;
+}
+
+/**
+ * Estimate memory required for an audio buffer
+ * @param duration Duration in seconds
+ * @param sampleRate Sample rate (default: 48000 Hz)
+ * @param channels Number of channels (default: 2 for stereo)
+ * @returns Estimated memory in MB
+ */
+export function estimateAudioMemory(
+  duration: number,
+  sampleRate: number = 48000,
+  channels: number = 2
+): number {
+  // Each sample is a 32-bit float (4 bytes)
+  const bytesPerSample = 4;
+  const totalSamples = duration * sampleRate * channels;
+  const bytes = totalSamples * bytesPerSample;
+
+  // Convert to MB
+  return bytes / (1024 * 1024);
+}
+
+/**
+ * Get available device memory if supported
+ * @returns Available memory in MB, or undefined if not supported
+ */
+export function getAvailableMemory(): number | undefined {
+  if (typeof navigator === 'undefined') return undefined;
+
+  // @ts-ignore - deviceMemory is not in TypeScript types yet
+  const deviceMemory = navigator.deviceMemory;
+  if (typeof deviceMemory === 'number') {
+    // deviceMemory is in GB, convert to MB
+    return deviceMemory * 1024;
+  }
+
+  return undefined;
+}
+
+/**
+ * Check if a file size is within safe memory limits
+ * @param fileSizeBytes File size in bytes
+ * @returns Memory check result
+ */
+export function checkFileMemoryLimit(fileSizeBytes: number): MemoryCheckResult {
+  // Estimate memory usage (audio files decompress to ~10x their size)
+  const estimatedMemoryMB = (fileSizeBytes / (1024 * 1024)) * 10;
+  const availableMemoryMB = getAvailableMemory();
+
+  // Conservative limits
+  const WARN_THRESHOLD_MB = 100; // Warn if file will use > 100MB
+  const MAX_RECOMMENDED_MB = 500; // Don't recommend files > 500MB
+
+  if (estimatedMemoryMB > MAX_RECOMMENDED_MB) {
+    return {
+      allowed: false,
+      warning: `This file may require ${Math.round(estimatedMemoryMB)}MB of memory. ` +
+               `Files larger than ${MAX_RECOMMENDED_MB}MB are not recommended as they may cause performance issues or crashes.`,
+      estimatedMemoryMB,
+      availableMemoryMB,
+    };
+  }
+
+  if (estimatedMemoryMB > WARN_THRESHOLD_MB) {
+    const warning = availableMemoryMB
+      ? `This file will require approximately ${Math.round(estimatedMemoryMB)}MB of memory. ` +
+        `Your device has ${Math.round(availableMemoryMB)}MB available.`
+      : `This file will require approximately ${Math.round(estimatedMemoryMB)}MB of memory. ` +
+        `Large files may cause performance issues on devices with limited memory.`;
+
+    return {
+      allowed: true,
+      warning,
+      estimatedMemoryMB,
+      availableMemoryMB,
+    };
+  }
+
+  return {
+    allowed: true,
+    estimatedMemoryMB,
+    availableMemoryMB,
+  };
+}
+
+/**
+ * Check if an audio buffer is within safe memory limits
+ * @param duration Duration in seconds
+ * @param sampleRate Sample rate
+ * @param channels Number of channels
+ * @returns Memory check result
+ */
+export function checkAudioBufferMemoryLimit(
+  duration: number,
+  sampleRate: number = 48000,
+  channels: number = 2
+): MemoryCheckResult {
+  const estimatedMemoryMB = estimateAudioMemory(duration, sampleRate, channels);
+  const availableMemoryMB = getAvailableMemory();
+
+  const WARN_THRESHOLD_MB = 100;
+  const MAX_RECOMMENDED_MB = 500;
+
+  if (estimatedMemoryMB > MAX_RECOMMENDED_MB) {
+    return {
+      allowed: false,
+      warning: `This audio (${Math.round(duration / 60)} minutes) will require ${Math.round(estimatedMemoryMB)}MB of memory. ` +
+               `Audio longer than ${Math.round((MAX_RECOMMENDED_MB / sampleRate / channels / 4) / 60)} minutes may cause performance issues.`,
+      estimatedMemoryMB,
+      availableMemoryMB,
+    };
+  }
+
+  if (estimatedMemoryMB > WARN_THRESHOLD_MB) {
+    const warning = availableMemoryMB
+      ? `This audio will require approximately ${Math.round(estimatedMemoryMB)}MB of memory. ` +
+        `Your device has ${Math.round(availableMemoryMB)}MB available.`
+      : `This audio will require approximately ${Math.round(estimatedMemoryMB)}MB of memory.`;
+
+    return {
+      allowed: true,
+      warning,
+      estimatedMemoryMB,
+      availableMemoryMB,
+    };
+  }
+
+  return {
+    allowed: true,
+    estimatedMemoryMB,
+    availableMemoryMB,
+  };
+}
+
+/**
+ * Format memory size in human-readable format
+ * @param bytes Size in bytes
+ * @returns Formatted string (e.g., "1.5 MB", "250 KB")
+ */
+export function formatMemorySize(bytes: number): string {
+  if (bytes < 1024) {
+    return `${bytes} B`;
+  } else if (bytes < 1024 * 1024) {
+    return `${(bytes / 1024).toFixed(1)} KB`;
+  } else if (bytes < 1024 * 1024 * 1024) {
+    return `${(bytes / (1024 * 1024)).toFixed(1)} MB`;
+  } else {
+    return `${(bytes / (1024 * 1024 * 1024)).toFixed(2)} GB`;
+  }
+}