Feat: Add public landing page for non-authenticated users

- Create /home route with SEO metadata and JSON-LD structured data
- Add hero section with dual CTAs (sign-up and PWA install)
- Add features section showcasing dual tracking, health timeline, achievements, savings
- Add animated phone demo with rotating screens (auto-advance, pause on hover)
- Add final CTA section and footer with affiliate disclosure
- Extract usePWAInstall hook for reusable PWA install logic
- Enhance theme-context with system preference auto-detection

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/app/home/page.tsx

@@ -0,0 +1,65 @@
+import { Metadata } from 'next';
+import { LandingPage } from '@/components/landing/LandingPage';
+
+export const metadata: Metadata = {
+  title: 'QuitTraq - Track Your Journey to Quit Smoking & Marijuana',
+  description: 'Free app to track nicotine and marijuana usage. Health recovery timeline, achievements, savings tracker. PWA works offline. Your companion to a healthier life.',
+  keywords: ['quit smoking', 'stop smoking app', 'nicotine tracker', 'marijuana tracker', 'health recovery', 'quit vaping', 'substance tracker'],
+  authors: [{ name: 'QuitTraq' }],
+  openGraph: {
+    type: 'website',
+    locale: 'en_US',
+    url: 'https://quittraq.com/home',
+    title: 'QuitTraq - Track Your Journey to Quit Smoking',
+    description: 'Free app to track nicotine and marijuana usage with health timeline and achievements.',
+    siteName: 'QuitTraq',
+    images: [
+      {
+        url: '/og-image.png',
+        width: 1200,
+        height: 630,
+        alt: 'QuitTraq - Quit Smoking App',
+      },
+    ],
+  },
+  twitter: {
+    card: 'summary_large_image',
+    title: 'QuitTraq - Track Your Journey to Quit Smoking',
+    description: 'Free app to track nicotine and marijuana usage with health timeline and achievements.',
+    images: ['/og-image.png'],
+  },
+  robots: {
+    index: true,
+    follow: true,
+    googleBot: {
+      index: true,
+      follow: true,
+    },
+  },
+};
+
+export default function HomePage() {
+  const jsonLd = {
+    '@context': 'https://schema.org',
+    '@type': 'WebApplication',
+    name: 'QuitTraq',
+    description: 'Track your journey to quit smoking and marijuana',
+    applicationCategory: 'HealthApplication',
+    operatingSystem: 'Any',
+    offers: {
+      '@type': 'Offer',
+      price: '0',
+      priceCurrency: 'USD',
+    },
+  };
+
+  return (
+    <>
+      <script
+        type="application/ld+json"
+        dangerouslySetInnerHTML={{ __html: JSON.stringify(jsonLd) }}
+      />
+      <LandingPage />
+    </>
+  );
+}

src/components/landing/CTASection.tsx

@@ -0,0 +1,224 @@
+'use client';
+
+import { useState } from 'react';
+import Link from 'next/link';
+import { Button } from '@/components/ui/button';
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogHeader,
+  DialogTitle,
+} from '@/components/ui/dialog';
+import { ArrowRight, Smartphone, Shield, CreditCard, Wifi, Download, Share, Plus, MoreVertical } from 'lucide-react';
+import { type PWAInstallState } from '@/hooks/usePWAInstall';
+
+interface CTASectionProps {
+  pwaInstall: PWAInstallState;
+}
+
+export function CTASection({ pwaInstall }: CTASectionProps) {
+  const [showInstructions, setShowInstructions] = useState(false);
+
+  const handleInstallClick = async () => {
+    if (pwaInstall.isInstallable) {
+      await pwaInstall.promptInstall();
+    } else {
+      setShowInstructions(true);
+    }
+  };
+
+  return (
+    <section
+      id="cta"
+      aria-labelledby="cta-heading"
+      className="py-20 px-4 relative overflow-hidden"
+    >
+      {/* Background gradient */}
+      <div className="absolute inset-0 bg-gradient-to-br from-primary/10 via-purple-500/5 to-pink-500/10 pointer-events-none" />
+      <div className="absolute top-1/2 left-1/2 -translate-x-1/2 -translate-y-1/2 w-[800px] h-[800px] bg-primary/10 rounded-full blur-[150px] pointer-events-none" />
+
+      <div className="container mx-auto max-w-4xl relative z-10 text-center">
+        {/* Headline */}
+        <h2
+          id="cta-heading"
+          className="text-3xl sm:text-4xl lg:text-5xl font-black tracking-tight mb-6"
+        >
+          Ready to Start Your{' '}
+          <span className="bg-gradient-to-r from-primary via-purple-500 to-pink-500 bg-clip-text text-transparent">
+            Journey?
+          </span>
+        </h2>
+
+        {/* Subheadline */}
+        <p className="text-lg sm:text-xl text-muted-foreground max-w-2xl mx-auto mb-10">
+          Join thousands of people taking control of their health. Your first step starts here.
+        </p>
+
+        {/* Dual CTAs */}
+        <div className="flex flex-col sm:flex-row gap-4 justify-center items-center mb-12">
+          <Button
+            asChild
+            size="lg"
+            className="h-14 px-8 text-lg rounded-xl bg-gradient-to-r from-primary to-purple-600 hover:from-primary/90 hover:to-purple-600/90 hover:scale-105 transition-all shadow-xl shadow-primary/25 hover-glow"
+          >
+            <Link href="/login">
+              Get Started Free
+              <ArrowRight className="ml-2 h-5 w-5" />
+            </Link>
+          </Button>
+
+          {!pwaInstall.isStandalone && (
+            <Button
+              size="lg"
+              variant="outline"
+              onClick={handleInstallClick}
+              aria-label="Install QuitTraq as an app on your device"
+              className="h-14 px-8 text-lg rounded-xl border-purple-500/30 hover:bg-purple-500/10 hover:scale-105 transition-all"
+            >
+              <Smartphone className="mr-2 h-5 w-5" />
+              Install App
+            </Button>
+          )}
+        </div>
+
+        {/* Trust signals */}
+        <div className="flex flex-wrap justify-center gap-6">
+          <div className="flex items-center gap-2 text-sm text-muted-foreground">
+            <CreditCard className="h-4 w-4 text-primary" />
+            <span>No Credit Card Required</span>
+          </div>
+          <div className="flex items-center gap-2 text-sm text-muted-foreground">
+            <Shield className="h-4 w-4 text-primary" />
+            <span>Privacy Focused</span>
+          </div>
+          <div className="flex items-center gap-2 text-sm text-muted-foreground">
+            <Wifi className="h-4 w-4 text-primary" />
+            <span>Works Offline</span>
+          </div>
+        </div>
+      </div>
+
+      {/* PWA Install Instructions Dialog */}
+      <Dialog open={showInstructions} onOpenChange={setShowInstructions}>
+        <DialogContent className="sm:max-w-md">
+          <DialogHeader>
+            <DialogTitle className="flex items-center gap-2">
+              <Download className="h-5 w-5 text-purple-400" />
+              Add QuitTraq to Home Screen
+            </DialogTitle>
+            <DialogDescription>
+              Get quick access to track your progress right from your phone&apos;s home screen.
+            </DialogDescription>
+          </DialogHeader>
+
+          <div className="space-y-6 py-4">
+            {pwaInstall.isIOS ? (
+              <div className="space-y-4">
+                <p className="text-sm font-medium text-purple-400">For iPhone / iPad (Safari):</p>
+                <ol className="space-y-4 text-sm">
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      1
+                    </span>
+                    <div>
+                      <p>
+                        Tap the <strong>Share</strong> button
+                      </p>
+                      <div className="mt-1 inline-flex items-center gap-1 rounded bg-muted px-2 py-1">
+                        <Share className="h-4 w-4" />
+                      </div>
+                    </div>
+                  </li>
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      2
+                    </span>
+                    <div>
+                      <p>
+                        Scroll down and tap <strong>&quot;Add to Home Screen&quot;</strong>
+                      </p>
+                      <div className="mt-1 inline-flex items-center gap-1 rounded bg-muted px-2 py-1">
+                        <Plus className="h-4 w-4" /> Add to Home Screen
+                      </div>
+                    </div>
+                  </li>
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      3
+                    </span>
+                    <p>
+                      Tap <strong>&quot;Add&quot;</strong> to confirm
+                    </p>
+                  </li>
+                </ol>
+              </div>
+            ) : pwaInstall.isAndroid ? (
+              <div className="space-y-4">
+                <p className="text-sm font-medium text-purple-400">For Android (Chrome):</p>
+                <ol className="space-y-4 text-sm">
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      1
+                    </span>
+                    <div>
+                      <p>
+                        Tap the <strong>menu</strong> button (3 dots)
+                      </p>
+                      <div className="mt-1 inline-flex items-center gap-1 rounded bg-muted px-2 py-1">
+                        <MoreVertical className="h-4 w-4" />
+                      </div>
+                    </div>
+                  </li>
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      2
+                    </span>
+                    <p>
+                      Tap <strong>&quot;Add to Home screen&quot;</strong> or{' '}
+                      <strong>&quot;Install app&quot;</strong>
+                    </p>
+                  </li>
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      3
+                    </span>
+                    <p>
+                      Tap <strong>&quot;Add&quot;</strong> or <strong>&quot;Install&quot;</strong> to
+                      confirm
+                    </p>
+                  </li>
+                </ol>
+              </div>
+            ) : (
+              <div className="space-y-4">
+                <p className="text-sm font-medium text-purple-400">On mobile device:</p>
+                <ul className="space-y-2 text-sm text-muted-foreground">
+                  <li>
+                    <strong>iPhone/iPad:</strong> Use Safari, tap Share &rarr; Add to Home Screen
+                  </li>
+                  <li>
+                    <strong>Android:</strong> Use Chrome, tap Menu &rarr; Add to Home screen
+                  </li>
+                </ul>
+                <p className="text-xs text-muted-foreground mt-4">
+                  Open this page on your phone to add QuitTraq to your home screen for quick access!
+                </p>
+              </div>
+            )}
+
+            <div className="pt-2 border-t border-white/10">
+              <p className="text-xs text-muted-foreground text-center">
+                Once added, tap the QuitTraq icon to quickly log your usage!
+              </p>
+            </div>
+          </div>
+
+          <Button onClick={() => setShowInstructions(false)} className="w-full">
+            Got it!
+          </Button>
+        </DialogContent>
+      </Dialog>
+    </section>
+  );
+}

src/components/landing/DemoSection.tsx

@@ -0,0 +1,267 @@
+'use client';
+
+import { useState, useEffect } from 'react';
+import { Cigarette, Leaf, Heart, Trophy, DollarSign, TrendingDown, CheckCircle } from 'lucide-react';
+
+const DEMO_SCREENS = [
+  {
+    id: 'logging',
+    title: 'Log Your Usage',
+    subtitle: 'Track daily consumption with ease',
+    content: (
+      <div className="space-y-4">
+        <div className="flex justify-between items-center p-3 rounded-xl bg-white/5 border border-white/10">
+          <div className="flex items-center gap-3">
+            <div className="w-8 h-8 rounded-lg bg-red-500/20 flex items-center justify-center">
+              <Cigarette className="h-4 w-4 text-red-400" />
+            </div>
+            <span className="font-medium">Nicotine</span>
+          </div>
+          <div className="text-2xl font-bold">3</div>
+        </div>
+        <div className="flex justify-between items-center p-3 rounded-xl bg-white/5 border border-white/10">
+          <div className="flex items-center gap-3">
+            <div className="w-8 h-8 rounded-lg bg-green-500/20 flex items-center justify-center">
+              <Leaf className="h-4 w-4 text-green-400" />
+            </div>
+            <span className="font-medium">Marijuana</span>
+          </div>
+          <div className="text-2xl font-bold">0</div>
+        </div>
+        <div className="text-center text-xs text-muted-foreground mt-4">
+          <TrendingDown className="h-4 w-4 inline mr-1 text-green-400" />
+          Down 40% from last week
+        </div>
+      </div>
+    ),
+  },
+  {
+    id: 'health',
+    title: 'Health Recovery',
+    subtitle: 'Watch your body heal',
+    content: (
+      <div className="space-y-3">
+        <div className="space-y-1">
+          <div className="flex justify-between text-xs">
+            <span>Blood Pressure Normalizes</span>
+            <CheckCircle className="h-3 w-3 text-green-400" />
+          </div>
+          <div className="h-2 rounded-full bg-white/10 overflow-hidden">
+            <div className="h-full w-full bg-gradient-to-r from-teal-500 to-cyan-400 rounded-full" />
+          </div>
+        </div>
+        <div className="space-y-1">
+          <div className="flex justify-between text-xs">
+            <span>Oxygen Levels Rise</span>
+            <CheckCircle className="h-3 w-3 text-green-400" />
+          </div>
+          <div className="h-2 rounded-full bg-white/10 overflow-hidden">
+            <div className="h-full w-full bg-gradient-to-r from-teal-500 to-cyan-400 rounded-full" />
+          </div>
+        </div>
+        <div className="space-y-1">
+          <div className="flex justify-between text-xs">
+            <span>Circulation Improves</span>
+            <span className="text-yellow-400">1 week to go</span>
+          </div>
+          <div className="h-2 rounded-full bg-white/10 overflow-hidden">
+            <div className="h-full w-3/4 bg-gradient-to-r from-teal-500 to-cyan-400 rounded-full" />
+          </div>
+        </div>
+        <div className="space-y-1">
+          <div className="flex justify-between text-xs">
+            <span>Heart Attack Risk Drops</span>
+            <span className="text-muted-foreground">2 weeks to go</span>
+          </div>
+          <div className="h-2 rounded-full bg-white/10 overflow-hidden">
+            <div className="h-full w-1/2 bg-gradient-to-r from-teal-500 to-cyan-400 rounded-full" />
+          </div>
+        </div>
+      </div>
+    ),
+  },
+  {
+    id: 'achievements',
+    title: 'Achievements',
+    subtitle: 'Celebrate every milestone',
+    content: (
+      <div className="grid grid-cols-3 gap-2">
+        {[
+          { name: 'First Step', unlocked: true },
+          { name: 'Hat Trick', unlocked: true },
+          { name: 'Week Warrior', unlocked: true },
+          { name: 'Fighter', unlocked: false },
+          { name: 'Monthly Master', unlocked: false },
+          { name: 'Goal Crusher', unlocked: false },
+        ].map((badge) => (
+          <div
+            key={badge.name}
+            className={`aspect-square rounded-xl flex flex-col items-center justify-center p-2 text-center ${
+              badge.unlocked
+                ? 'bg-gradient-to-br from-yellow-500/30 to-amber-600/20 border border-yellow-500/50'
+                : 'bg-white/5 border border-white/10 opacity-50'
+            }`}
+          >
+            <Trophy
+              className={`h-5 w-5 mb-1 ${badge.unlocked ? 'text-yellow-400' : 'text-muted-foreground'}`}
+            />
+            <span className="text-[10px] leading-tight">{badge.name}</span>
+          </div>
+        ))}
+      </div>
+    ),
+  },
+  {
+    id: 'savings',
+    title: 'Money Saved',
+    subtitle: 'Track your financial wins',
+    content: (
+      <div className="text-center space-y-4">
+        <div className="w-16 h-16 rounded-2xl bg-emerald-500/20 flex items-center justify-center mx-auto">
+          <DollarSign className="h-8 w-8 text-emerald-400" />
+        </div>
+        <div>
+          <div className="text-4xl font-black text-emerald-400">$127.50</div>
+          <div className="text-sm text-muted-foreground">saved this month</div>
+        </div>
+        <div className="grid grid-cols-2 gap-2 text-xs">
+          <div className="p-2 rounded-lg bg-white/5 border border-white/10">
+            <div className="font-bold">$4.25</div>
+            <div className="text-muted-foreground">per day</div>
+          </div>
+          <div className="p-2 rounded-lg bg-white/5 border border-white/10">
+            <div className="font-bold">$1,530</div>
+            <div className="text-muted-foreground">per year</div>
+          </div>
+        </div>
+      </div>
+    ),
+  },
+];
+
+export function DemoSection() {
+  const [activeScreen, setActiveScreen] = useState(0);
+  const [isPaused, setIsPaused] = useState(false);
+
+  useEffect(() => {
+    if (isPaused) return;
+
+    const interval = setInterval(() => {
+      setActiveScreen((prev) => (prev + 1) % DEMO_SCREENS.length);
+    }, 4000);
+
+    return () => clearInterval(interval);
+  }, [isPaused]);
+
+  return (
+    <section
+      id="demo"
+      aria-labelledby="demo-heading"
+      className="py-20 px-4 relative overflow-hidden"
+    >
+      {/* Background accents */}
+      <div className="absolute top-1/2 left-0 w-96 h-96 bg-primary/10 rounded-full blur-[120px] -translate-y-1/2 pointer-events-none" />
+      <div className="absolute top-1/2 right-0 w-96 h-96 bg-purple-500/10 rounded-full blur-[120px] -translate-y-1/2 pointer-events-none" />
+
+      <div className="container mx-auto max-w-6xl relative z-10">
+        {/* Section Header */}
+        <div className="text-center mb-12">
+          <h2
+            id="demo-heading"
+            className="text-3xl sm:text-4xl font-bold mb-4"
+          >
+            See It In{' '}
+            <span className="bg-gradient-to-r from-primary via-purple-500 to-pink-500 bg-clip-text text-transparent">
+              Action
+            </span>
+          </h2>
+          <p className="text-muted-foreground max-w-2xl mx-auto">
+            A quick look at how QuitTraq helps you track progress and stay motivated.
+          </p>
+        </div>
+
+        <div className="flex flex-col lg:flex-row items-center gap-12 lg:gap-16">
+          {/* Phone Mockup */}
+          <div
+            className="relative mx-auto lg:mx-0"
+            onMouseEnter={() => setIsPaused(true)}
+            onMouseLeave={() => setIsPaused(false)}
+            onTouchStart={() => setIsPaused(true)}
+            onTouchEnd={() => setIsPaused(false)}
+          >
+            {/* Phone frame glow */}
+            <div className="absolute inset-0 bg-gradient-to-br from-primary/30 to-purple-500/30 rounded-[3rem] blur-2xl opacity-50" />
+
+            {/* Phone frame */}
+            <div className="relative w-[280px] sm:w-[320px] aspect-[9/16] rounded-[2.5rem] overflow-hidden border-4 border-white/10 bg-background shadow-2xl shadow-black/30">
+              {/* Notch */}
+              <div className="absolute top-0 left-1/2 -translate-x-1/2 w-24 h-6 bg-black rounded-b-2xl z-20" />
+
+              {/* Screen content */}
+              <div className="absolute inset-0 p-4 pt-10">
+                {/* Screen header */}
+                <div className="text-center mb-4">
+                  <h3 className="text-lg font-bold">{DEMO_SCREENS[activeScreen].title}</h3>
+                  <p className="text-xs text-muted-foreground">
+                    {DEMO_SCREENS[activeScreen].subtitle}
+                  </p>
+                </div>
+
+                {/* Screen content with transition */}
+                <div className="animate-fade-in" key={activeScreen}>
+                  {DEMO_SCREENS[activeScreen].content}
+                </div>
+              </div>
+
+              {/* Bottom gradient overlay */}
+              <div className="absolute bottom-0 left-0 right-0 h-20 bg-gradient-to-t from-background to-transparent pointer-events-none" />
+            </div>
+          </div>
+
+          {/* Description and indicators */}
+          <div className="flex-1 text-center lg:text-left">
+            <div className="space-y-6">
+              {/* Screen descriptions */}
+              {DEMO_SCREENS.map((screen, index) => (
+                <button
+                  key={screen.id}
+                  onClick={() => setActiveScreen(index)}
+                  className={`w-full text-left p-4 rounded-xl transition-all duration-300 ${
+                    activeScreen === index
+                      ? 'bg-primary/10 border border-primary/30'
+                      : 'hover:bg-white/5 border border-transparent'
+                  }`}
+                >
+                  <h4
+                    className={`font-semibold mb-1 ${
+                      activeScreen === index ? 'text-primary' : 'text-foreground'
+                    }`}
+                  >
+                    {screen.title}
+                  </h4>
+                  <p className="text-sm text-muted-foreground">{screen.subtitle}</p>
+                </button>
+              ))}
+            </div>
+
+            {/* Dot indicators (mobile) */}
+            <div className="flex justify-center gap-2 mt-6 lg:hidden">
+              {DEMO_SCREENS.map((_, index) => (
+                <button
+                  key={index}
+                  onClick={() => setActiveScreen(index)}
+                  className={`w-2 h-2 rounded-full transition-all ${
+                    activeScreen === index
+                      ? 'w-6 bg-primary'
+                      : 'bg-white/20 hover:bg-white/40'
+                  }`}
+                  aria-label={`Go to screen ${index + 1}`}
+                />
+              ))}
+            </div>
+          </div>
+        </div>
+      </div>
+    </section>
+  );
+}

src/components/landing/FeatureCard.tsx

@@ -0,0 +1,78 @@
+'use client';
+
+import { useRef, useEffect, useState } from 'react';
+import { Card, CardContent, CardHeader, CardTitle } from '@/components/ui/card';
+import { LucideIcon } from 'lucide-react';
+
+interface FeatureIcon {
+  Icon: LucideIcon;
+  color: string;
+  bg: string;
+}
+
+interface FeatureCardProps {
+  title: string;
+  description: string;
+  icons: FeatureIcon[];
+  gradient: string;
+  delay?: number;
+}
+
+export function FeatureCard({ title, description, icons, gradient, delay = 0 }: FeatureCardProps) {
+  const ref = useRef<HTMLDivElement>(null);
+  const [isInView, setIsInView] = useState(false);
+
+  useEffect(() => {
+    const observer = new IntersectionObserver(
+      ([entry]) => {
+        if (entry.isIntersecting) {
+          setIsInView(true);
+          observer.disconnect();
+        }
+      },
+      { threshold: 0.1 }
+    );
+
+    if (ref.current) {
+      observer.observe(ref.current);
+    }
+
+    return () => observer.disconnect();
+  }, []);
+
+  return (
+    <div
+      ref={ref}
+      className={`opacity-0 ${isInView ? 'animate-fade-in-up' : ''}`}
+      style={{ animationDelay: `${delay}ms` }}
+    >
+      <Card
+        className="relative backdrop-blur-xl border border-white/10 shadow-xl hover-lift transition-all duration-300 h-full overflow-hidden group"
+        style={{
+          background: `linear-gradient(135deg, ${gradient})`,
+        }}
+      >
+        {/* Decorative gradient orb */}
+        <div className="absolute top-0 right-0 w-40 h-40 bg-gradient-to-br from-white/10 to-transparent rounded-full -translate-y-1/2 translate-x-1/2 pointer-events-none group-hover:scale-110 transition-transform duration-500" />
+
+        <CardHeader className="relative z-10">
+          <div className="flex items-center gap-2 mb-3">
+            {icons.map((icon, index) => (
+              <div
+                key={index}
+                className={`w-10 h-10 rounded-xl ${icon.bg} flex items-center justify-center`}
+              >
+                <icon.Icon className={`h-5 w-5 ${icon.color}`} />
+              </div>
+            ))}
+          </div>
+          <CardTitle className="text-xl font-bold text-foreground">{title}</CardTitle>
+        </CardHeader>
+
+        <CardContent className="relative z-10">
+          <p className="text-muted-foreground leading-relaxed">{description}</p>
+        </CardContent>
+      </Card>
+    </div>
+  );
+}

src/components/landing/FeaturesSection.tsx

@@ -0,0 +1,88 @@
+'use client';
+
+import { FeatureCard } from './FeatureCard';
+import { Cigarette, Leaf, Heart, Trophy, DollarSign } from 'lucide-react';
+
+const FEATURES = [
+  {
+    id: 'dual-tracking',
+    title: 'Dual Substance Tracking',
+    description:
+      'Track both nicotine and marijuana independently. Each substance has its own stats, timeline, and achievements to support your unique journey.',
+    icons: [
+      { Icon: Cigarette, color: 'text-red-400', bg: 'bg-red-500/20' },
+      { Icon: Leaf, color: 'text-green-400', bg: 'bg-green-500/20' },
+    ],
+    gradient: 'rgba(239, 68, 68, 0.15) 0%, rgba(34, 197, 94, 0.15) 100%',
+  },
+  {
+    id: 'health-timeline',
+    title: 'Health Recovery Timeline',
+    description:
+      'Watch your body heal in real-time. From 20 minutes to 1 year, track every health milestone as your body recovers and gets stronger.',
+    icons: [{ Icon: Heart, color: 'text-teal-400', bg: 'bg-teal-500/20' }],
+    gradient: 'rgba(20, 184, 166, 0.15) 0%, rgba(6, 182, 212, 0.1) 100%',
+  },
+  {
+    id: 'achievements',
+    title: 'Achievements & Badges',
+    description:
+      'Unlock badges as you progress. First Step, Week Warrior, Goal Crusher - celebrate every win and stay motivated on your journey.',
+    icons: [{ Icon: Trophy, color: 'text-yellow-400', bg: 'bg-yellow-500/20' }],
+    gradient: 'rgba(234, 179, 8, 0.15) 0%, rgba(245, 158, 11, 0.1) 100%',
+  },
+  {
+    id: 'savings',
+    title: 'Money Savings Tracker',
+    description:
+      'See how much you save by cutting back. Set your goals and watch your savings grow daily - extra motivation to keep going.',
+    icons: [{ Icon: DollarSign, color: 'text-emerald-400', bg: 'bg-emerald-500/20' }],
+    gradient: 'rgba(16, 185, 129, 0.15) 0%, rgba(34, 197, 94, 0.1) 100%',
+  },
+];
+
+export function FeaturesSection() {
+  return (
+    <section
+      id="features"
+      aria-labelledby="features-heading"
+      className="py-20 px-4 relative"
+    >
+      {/* Background accent */}
+      <div className="absolute inset-0 bg-gradient-to-b from-transparent via-primary/5 to-transparent pointer-events-none" />
+
+      <div className="container mx-auto max-w-6xl relative z-10">
+        {/* Section Header */}
+        <div className="text-center mb-16">
+          <h2
+            id="features-heading"
+            className="text-3xl sm:text-4xl font-bold mb-4"
+          >
+            Everything You Need to{' '}
+            <span className="bg-gradient-to-r from-primary via-purple-500 to-pink-500 bg-clip-text text-transparent">
+              Succeed
+            </span>
+          </h2>
+          <p className="text-muted-foreground max-w-2xl mx-auto">
+            Built with empathy and designed for your success. Every feature supports your journey
+            to a healthier, happier life.
+          </p>
+        </div>
+
+        {/* Features Grid */}
+        <div className="grid sm:grid-cols-2 gap-6">
+          {FEATURES.map((feature, index) => (
+            <FeatureCard
+              key={feature.id}
+              title={feature.title}
+              description={feature.description}
+              icons={feature.icons}
+              gradient={feature.gradient}
+              delay={index * 100}
+            />
+          ))}
+        </div>
+      </div>
+    </section>
+  );
+}

src/components/landing/HeroSection.tsx

@@ -0,0 +1,233 @@
+'use client';
+
+import { useState } from 'react';
+import Link from 'next/link';
+import { Button } from '@/components/ui/button';
+import {
+  Dialog,
+  DialogContent,
+  DialogDescription,
+  DialogHeader,
+  DialogTitle,
+} from '@/components/ui/dialog';
+import { ArrowRight, Smartphone, CheckCircle, Shield, Wifi, Download, Share, Plus, MoreVertical } from 'lucide-react';
+import { type PWAInstallState } from '@/hooks/usePWAInstall';
+
+interface HeroSectionProps {
+  pwaInstall: PWAInstallState;
+}
+
+export function HeroSection({ pwaInstall }: HeroSectionProps) {
+  const [showInstructions, setShowInstructions] = useState(false);
+
+  const handleInstallClick = async () => {
+    if (pwaInstall.isInstallable) {
+      await pwaInstall.promptInstall();
+    } else {
+      setShowInstructions(true);
+    }
+  };
+
+  return (
+    <section
+      id="hero"
+      aria-labelledby="hero-heading"
+      className="min-h-screen flex items-center justify-center px-4 pt-24 pb-16 relative overflow-hidden"
+    >
+      {/* Background decorative elements */}
+      <div className="absolute top-1/4 left-1/4 w-96 h-96 bg-primary/20 rounded-full blur-[120px] animate-pulse-subtle pointer-events-none" />
+      <div className="absolute bottom-1/4 right-1/4 w-96 h-96 bg-purple-500/15 rounded-full blur-[120px] animate-pulse-subtle delay-500 pointer-events-none" />
+      <div className="absolute top-1/2 left-1/2 -translate-x-1/2 -translate-y-1/2 w-[600px] h-[600px] bg-gradient-to-br from-primary/10 to-purple-500/10 rounded-full blur-[150px] pointer-events-none" />
+
+      <div className="container mx-auto max-w-5xl text-center relative z-10">
+        {/* Badge */}
+        <div className="inline-flex items-center gap-2 px-4 py-2 rounded-full bg-primary/10 border border-primary/20 mb-8 animate-fade-in">
+          <CheckCircle className="h-4 w-4 text-primary" />
+          <span className="text-sm font-medium text-primary">Free & Works Offline</span>
+        </div>
+
+        {/* Headline */}
+        <h1
+          id="hero-heading"
+          className="text-4xl sm:text-5xl lg:text-6xl font-black tracking-tight mb-6 animate-fade-in-up"
+        >
+          <span className="bg-gradient-to-r from-primary via-purple-500 to-pink-500 bg-clip-text text-transparent">
+            Take Control
+          </span>
+          <br />
+          <span className="text-foreground">of Your Journey</span>
+        </h1>
+
+        {/* Subheadline */}
+        <p className="text-lg sm:text-xl text-muted-foreground max-w-2xl mx-auto mb-10 animate-fade-in-up delay-200">
+          Track nicotine and marijuana usage, celebrate milestones, and watch your health recover.
+          Your companion to a healthier life.
+        </p>
+
+        {/* Dual CTAs */}
+        <div className="flex flex-col sm:flex-row gap-4 justify-center items-center animate-fade-in-up delay-300">
+          <Button
+            asChild
+            size="lg"
+            className="h-14 px-8 text-lg rounded-xl bg-gradient-to-r from-primary to-purple-600 hover:from-primary/90 hover:to-purple-600/90 hover:scale-105 transition-all shadow-xl shadow-primary/25"
+          >
+            <Link href="/login">
+              Get Started Free
+              <ArrowRight className="ml-2 h-5 w-5" />
+            </Link>
+          </Button>
+
+          {!pwaInstall.isStandalone && (
+            <Button
+              size="lg"
+              variant="outline"
+              onClick={handleInstallClick}
+              aria-label="Install QuitTraq as an app on your device"
+              className="h-14 px-8 text-lg rounded-xl border-purple-500/30 hover:bg-purple-500/10 hover:scale-105 transition-all"
+            >
+              <Smartphone className="mr-2 h-5 w-5" />
+              Install App
+            </Button>
+          )}
+        </div>
+
+        {/* Trust signals */}
+        <div className="flex flex-wrap justify-center gap-6 mt-12 animate-fade-in-up delay-400">
+          <div className="flex items-center gap-2 text-sm text-muted-foreground">
+            <Shield className="h-4 w-4 text-primary" />
+            <span>Privacy First</span>
+          </div>
+          <div className="flex items-center gap-2 text-sm text-muted-foreground">
+            <Wifi className="h-4 w-4 text-primary" />
+            <span>Works Offline</span>
+          </div>
+          <div className="flex items-center gap-2 text-sm text-muted-foreground">
+            <CheckCircle className="h-4 w-4 text-primary" />
+            <span>Always Free</span>
+          </div>
+        </div>
+      </div>
+
+      {/* PWA Install Instructions Dialog */}
+      <Dialog open={showInstructions} onOpenChange={setShowInstructions}>
+        <DialogContent className="sm:max-w-md">
+          <DialogHeader>
+            <DialogTitle className="flex items-center gap-2">
+              <Download className="h-5 w-5 text-purple-400" />
+              Add QuitTraq to Home Screen
+            </DialogTitle>
+            <DialogDescription>
+              Get quick access to track your progress right from your phone&apos;s home screen.
+            </DialogDescription>
+          </DialogHeader>
+
+          <div className="space-y-6 py-4">
+            {pwaInstall.isIOS ? (
+              <div className="space-y-4">
+                <p className="text-sm font-medium text-purple-400">For iPhone / iPad (Safari):</p>
+                <ol className="space-y-4 text-sm">
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      1
+                    </span>
+                    <div>
+                      <p>
+                        Tap the <strong>Share</strong> button
+                      </p>
+                      <div className="mt-1 inline-flex items-center gap-1 rounded bg-muted px-2 py-1">
+                        <Share className="h-4 w-4" />
+                      </div>
+                    </div>
+                  </li>
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      2
+                    </span>
+                    <div>
+                      <p>
+                        Scroll down and tap <strong>&quot;Add to Home Screen&quot;</strong>
+                      </p>
+                      <div className="mt-1 inline-flex items-center gap-1 rounded bg-muted px-2 py-1">
+                        <Plus className="h-4 w-4" /> Add to Home Screen
+                      </div>
+                    </div>
+                  </li>
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      3
+                    </span>
+                    <p>
+                      Tap <strong>&quot;Add&quot;</strong> to confirm
+                    </p>
+                  </li>
+                </ol>
+              </div>
+            ) : pwaInstall.isAndroid ? (
+              <div className="space-y-4">
+                <p className="text-sm font-medium text-purple-400">For Android (Chrome):</p>
+                <ol className="space-y-4 text-sm">
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      1
+                    </span>
+                    <div>
+                      <p>
+                        Tap the <strong>menu</strong> button (3 dots)
+                      </p>
+                      <div className="mt-1 inline-flex items-center gap-1 rounded bg-muted px-2 py-1">
+                        <MoreVertical className="h-4 w-4" />
+                      </div>
+                    </div>
+                  </li>
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      2
+                    </span>
+                    <p>
+                      Tap <strong>&quot;Add to Home screen&quot;</strong> or{' '}
+                      <strong>&quot;Install app&quot;</strong>
+                    </p>
+                  </li>
+                  <li className="flex items-start gap-3">
+                    <span className="flex h-6 w-6 shrink-0 items-center justify-center rounded-full bg-purple-500/20 text-purple-400 text-xs font-bold">
+                      3
+                    </span>
+                    <p>
+                      Tap <strong>&quot;Add&quot;</strong> or <strong>&quot;Install&quot;</strong> to
+                      confirm
+                    </p>
+                  </li>
+                </ol>
+              </div>
+            ) : (
+              <div className="space-y-4">
+                <p className="text-sm font-medium text-purple-400">On mobile device:</p>
+                <ul className="space-y-2 text-sm text-muted-foreground">
+                  <li>
+                    <strong>iPhone/iPad:</strong> Use Safari, tap Share &rarr; Add to Home Screen
+                  </li>
+                  <li>
+                    <strong>Android:</strong> Use Chrome, tap Menu &rarr; Add to Home screen
+                  </li>
+                </ul>
+                <p className="text-xs text-muted-foreground mt-4">
+                  Open this page on your phone to add QuitTraq to your home screen for quick access!
+                </p>
+              </div>
+            )}
+
+            <div className="pt-2 border-t border-white/10">
+              <p className="text-xs text-muted-foreground text-center">
+                Once added, tap the QuitTraq icon to quickly log your usage!
+              </p>
+            </div>
+          </div>
+
+          <Button onClick={() => setShowInstructions(false)} className="w-full">
+            Got it!
+          </Button>
+        </DialogContent>
+      </Dialog>
+    </section>
+  );
+}

src/components/landing/LandingFooter.tsx

@@ -0,0 +1,107 @@
+'use client';
+
+import Link from 'next/link';
+
+const footerLinks = {
+  product: [
+    { label: 'Features', href: '#features' },
+    { label: 'Demo', href: '#demo' },
+    { label: 'Get Started', href: '#cta' },
+  ],
+  legal: [
+    { label: 'Privacy Policy', href: '/privacy' },
+    { label: 'Terms of Service', href: '/terms' },
+  ],
+};
+
+export function LandingFooter() {
+  const currentYear = new Date().getFullYear();
+
+  const handleAnchorClick = (href: string) => {
+    if (href.startsWith('#')) {
+      const element = document.querySelector(href);
+      if (element) {
+        element.scrollIntoView({ behavior: 'smooth' });
+      }
+    }
+  };
+
+  return (
+    <footer role="contentinfo" className="border-t border-white/10 bg-background/50 backdrop-blur-sm">
+      <div className="container mx-auto max-w-6xl px-4 py-12">
+        <div className="grid gap-8 sm:grid-cols-2 lg:grid-cols-4">
+          {/* Brand */}
+          <div className="sm:col-span-2 lg:col-span-2">
+            <Link href="/home" className="flex items-center gap-2 mb-4">
+              <div className="w-9 h-9 bg-gradient-to-br from-primary to-purple-600 rounded-xl flex items-center justify-center shadow-lg shadow-primary/20">
+                <span className="text-lg font-black text-white">Q</span>
+              </div>
+              <span className="text-xl font-black tracking-tight">QuitTraq</span>
+            </Link>
+            <p className="text-sm text-muted-foreground max-w-sm mb-4">
+              Your companion to a healthier life. Track your progress, celebrate milestones, and take
+              control of your journey.
+            </p>
+          </div>
+
+          {/* Product Links */}
+          <div>
+            <h3 className="font-semibold mb-4">Product</h3>
+            <ul className="space-y-2">
+              {footerLinks.product.map((link) => (
+                <li key={link.href}>
+                  {link.href.startsWith('#') ? (
+                    <button
+                      onClick={() => handleAnchorClick(link.href)}
+                      className="text-sm text-muted-foreground hover:text-foreground transition-colors"
+                    >
+                      {link.label}
+                    </button>
+                  ) : (
+                    <Link
+                      href={link.href}
+                      className="text-sm text-muted-foreground hover:text-foreground transition-colors"
+                    >
+                      {link.label}
+                    </Link>
+                  )}
+                </li>
+              ))}
+            </ul>
+          </div>
+
+          {/* Legal Links */}
+          <div>
+            <h3 className="font-semibold mb-4">Legal</h3>
+            <ul className="space-y-2">
+              {footerLinks.legal.map((link) => (
+                <li key={link.href}>
+                  <Link
+                    href={link.href}
+                    className="text-sm text-muted-foreground hover:text-foreground transition-colors"
+                  >
+                    {link.label}
+                  </Link>
+                </li>
+              ))}
+            </ul>
+          </div>
+        </div>
+
+        {/* Affiliate Disclosure */}
+        <div className="mt-12 pt-8 border-t border-white/10">
+          <p className="text-xs text-muted-foreground text-center max-w-2xl mx-auto mb-6">
+            QuitTraq may contain affiliate links. We may earn a small commission when you purchase
+            products through our links, at no extra cost to you. This helps support the free features
+            of the app.
+          </p>
+
+          {/* Copyright */}
+          <p className="text-xs text-muted-foreground text-center">
+            &copy; {currentYear} QuitTraq. All rights reserved.
+          </p>
+        </div>
+      </div>
+    </footer>
+  );
+}

src/components/landing/LandingNav.tsx

@@ -0,0 +1,142 @@
+'use client';
+
+import { useState } from 'react';
+import Link from 'next/link';
+import { Button } from '@/components/ui/button';
+import { Menu, X, Sun, Moon } from 'lucide-react';
+
+interface LandingNavProps {
+  theme: 'dark' | 'light';
+  toggleTheme: () => void;
+}
+
+const navLinks = [
+  { href: '#features', label: 'Features' },
+  { href: '#demo', label: 'Demo' },
+  { href: '#cta', label: 'Get Started' },
+];
+
+export function LandingNav({ theme, toggleTheme }: LandingNavProps) {
+  const [mobileMenuOpen, setMobileMenuOpen] = useState(false);
+
+  const handleNavClick = (href: string) => {
+    setMobileMenuOpen(false);
+    // Smooth scroll handled by CSS (scroll-behavior: smooth)
+    const element = document.querySelector(href);
+    if (element) {
+      element.scrollIntoView({ behavior: 'smooth' });
+    }
+  };
+
+  return (
+    <header
+      role="banner"
+      className="fixed top-0 left-0 right-0 z-50 bg-background/80 backdrop-blur-xl border-b border-white/10"
+    >
+      <nav
+        role="navigation"
+        aria-label="Main navigation"
+        className="container mx-auto max-w-6xl px-4 h-16 flex items-center justify-between"
+      >
+        {/* Logo */}
+        <Link
+          href="/home"
+          className="flex items-center gap-2 group"
+          onClick={() => window.scrollTo({ top: 0, behavior: 'smooth' })}
+        >
+          <div className="w-9 h-9 bg-gradient-to-br from-primary to-purple-600 rounded-xl flex items-center justify-center shadow-lg shadow-primary/20 group-hover:scale-105 transition-transform">
+            <span className="text-lg font-black text-white">Q</span>
+          </div>
+          <span className="text-xl font-black tracking-tight bg-gradient-to-br from-foreground to-foreground/70 bg-clip-text text-transparent">
+            QuitTraq
+          </span>
+        </Link>
+
+        {/* Desktop Navigation */}
+        <div className="hidden md:flex items-center gap-6">
+          {navLinks.map((link) => (
+            <button
+              key={link.href}
+              onClick={() => handleNavClick(link.href)}
+              className="text-sm font-medium text-muted-foreground hover:text-foreground transition-colors"
+            >
+              {link.label}
+            </button>
+          ))}
+        </div>
+
+        {/* Actions */}
+        <div className="flex items-center gap-2">
+          {/* Theme Toggle */}
+          <Button
+            variant="ghost"
+            size="icon"
+            onClick={toggleTheme}
+            aria-label={`Switch to ${theme === 'dark' ? 'light' : 'dark'} mode`}
+            className="text-muted-foreground hover:text-foreground"
+          >
+            {theme === 'dark' ? (
+              <Sun className="h-5 w-5" />
+            ) : (
+              <Moon className="h-5 w-5" />
+            )}
+          </Button>
+
+          {/* Login Button - Desktop */}
+          <Button
+            asChild
+            size="sm"
+            className="hidden md:inline-flex bg-gradient-to-r from-primary to-purple-600 hover:from-primary/90 hover:to-purple-600/90"
+          >
+            <Link href="/login">Sign In</Link>
+          </Button>
+
+          {/* Mobile Menu Toggle */}
+          <Button
+            variant="ghost"
+            size="icon"
+            className="md:hidden"
+            onClick={() => setMobileMenuOpen(!mobileMenuOpen)}
+            aria-label={mobileMenuOpen ? 'Close menu' : 'Open menu'}
+            aria-expanded={mobileMenuOpen}
+            aria-controls="mobile-menu"
+          >
+            {mobileMenuOpen ? (
+              <X className="h-5 w-5" />
+            ) : (
+              <Menu className="h-5 w-5" />
+            )}
+          </Button>
+        </div>
+      </nav>
+
+      {/* Mobile Menu */}
+      {mobileMenuOpen && (
+        <div
+          id="mobile-menu"
+          className="md:hidden bg-background/95 backdrop-blur-xl border-b border-white/10 animate-fade-in"
+        >
+          <div className="container mx-auto px-4 py-4 space-y-2">
+            {navLinks.map((link) => (
+              <button
+                key={link.href}
+                onClick={() => handleNavClick(link.href)}
+                className="block w-full text-left px-4 py-3 rounded-lg text-sm font-medium text-muted-foreground hover:text-foreground hover:bg-accent transition-colors"
+              >
+                {link.label}
+              </button>
+            ))}
+            <div className="pt-2 border-t border-white/10">
+              <Button
+                asChild
+                className="w-full bg-gradient-to-r from-primary to-purple-600"
+              >
+                <Link href="/login">Sign In</Link>
+              </Button>
+            </div>
+          </div>
+        </div>
+      )}
+    </header>
+  );
+}

src/components/landing/LandingPage.tsx

@@ -0,0 +1,38 @@
+'use client';
+
+import { useTheme } from '@/lib/theme-context';
+import { LandingNav } from './LandingNav';
+import { HeroSection } from './HeroSection';
+import { FeaturesSection } from './FeaturesSection';
+import { DemoSection } from './DemoSection';
+import { CTASection } from './CTASection';
+import { LandingFooter } from './LandingFooter';
+import { usePWAInstall } from '@/hooks/usePWAInstall';
+
+export function LandingPage() {
+  const { theme, toggleTheme } = useTheme();
+  const pwaInstall = usePWAInstall();
+
+  return (
+    <div className="min-h-screen bg-background">
+      {/* Skip link for accessibility */}
+      <a
+        href="#main-content"
+        className="sr-only focus:not-sr-only focus:absolute focus:top-4 focus:left-4 focus:z-50 focus:px-4 focus:py-2 focus:bg-primary focus:text-white focus:rounded-lg"
+      >
+        Skip to main content
+      </a>
+
+      <LandingNav theme={theme} toggleTheme={toggleTheme} />
+
+      <main id="main-content" role="main">
+        <HeroSection pwaInstall={pwaInstall} />
+        <FeaturesSection />
+        <DemoSection />
+        <CTASection pwaInstall={pwaInstall} />
+      </main>
+
+      <LandingFooter />
+    </div>
+  );
+}

src/hooks/usePWAInstall.ts

@@ -0,0 +1,78 @@
+'use client';
+
+import { useState, useEffect, useCallback } from 'react';
+
+interface BeforeInstallPromptEvent extends Event {
+  prompt: () => Promise<void>;
+  userChoice: Promise<{ outcome: 'accepted' | 'dismissed' }>;
+}
+
+export interface PWAInstallState {
+  isInstallable: boolean;
+  isStandalone: boolean;
+  isIOS: boolean;
+  isAndroid: boolean;
+  needsManualInstructions: boolean;
+  promptInstall: () => Promise<{ outcome: 'accepted' | 'dismissed' | 'unavailable' }>;
+}
+
+export function usePWAInstall(): PWAInstallState {
+  const [deferredPrompt, setDeferredPrompt] = useState<BeforeInstallPromptEvent | null>(null);
+  const [isIOS, setIsIOS] = useState(false);
+  const [isAndroid, setIsAndroid] = useState(false);
+  const [isStandalone, setIsStandalone] = useState(false);
+  const [isInstallable, setIsInstallable] = useState(false);
+
+  useEffect(() => {
+    // Check if already installed as PWA
+    const isAppInstalled =
+      window.matchMedia('(display-mode: standalone)').matches ||
+      (window.navigator as Navigator & { standalone?: boolean }).standalone === true;
+    setIsStandalone(isAppInstalled);
+
+    // Detect platform
+    const userAgent = window.navigator.userAgent.toLowerCase();
+    const isIOSDevice = /iphone|ipad|ipod/.test(userAgent);
+    const isAndroidDevice = /android/.test(userAgent);
+    setIsIOS(isIOSDevice);
+    setIsAndroid(isAndroidDevice);
+
+    // Listen for beforeinstallprompt (Android/Chrome)
+    const handleBeforeInstallPrompt = (e: Event) => {
+      e.preventDefault();
+      setDeferredPrompt(e as BeforeInstallPromptEvent);
+      setIsInstallable(true);
+    };
+
+    window.addEventListener('beforeinstallprompt', handleBeforeInstallPrompt);
+
+    return () => {
+      window.removeEventListener('beforeinstallprompt', handleBeforeInstallPrompt);
+    };
+  }, []);
+
+  const promptInstall = useCallback(async (): Promise<{ outcome: 'accepted' | 'dismissed' | 'unavailable' }> => {
+    if (!deferredPrompt) {
+      return { outcome: 'unavailable' };
+    }
+
+    await deferredPrompt.prompt();
+    const { outcome } = await deferredPrompt.userChoice;
+
+    if (outcome === 'accepted') {
+      setDeferredPrompt(null);
+      setIsInstallable(false);
+    }
+
+    return { outcome };
+  }, [deferredPrompt]);
+
+  return {
+    isInstallable,
+    isStandalone,
+    isIOS,
+    isAndroid,
+    needsManualInstructions: !deferredPrompt && (isIOS || isAndroid),
+    promptInstall,
+  };
+}

src/lib/theme-context.tsx

@@ -15,10 +15,31 @@ export function ThemeProvider({ children }: { children: ReactNode }) {
   const [theme, setTheme] = useState<Theme>('dark');
 
   useEffect(() => {
+    // Check localStorage first
     const saved = localStorage.getItem('theme') as Theme | null;
     if (saved) {
       setTheme(saved);
+      return;
     }
+
+    // Fall back to system preference
+    const prefersDark = window.matchMedia('(prefers-color-scheme: dark)').matches;
+    setTheme(prefersDark ? 'dark' : 'light');
+  }, []);
+
+  // Listen for system preference changes (only if no manual preference set)
+  useEffect(() => {
+    const mediaQuery = window.matchMedia('(prefers-color-scheme: dark)');
+
+    const handleChange = (e: MediaQueryListEvent) => {
+      // Only update if user hasn't manually set a preference
+      if (!localStorage.getItem('theme')) {
+        setTheme(e.matches ? 'dark' : 'light');
+      }
+    };
+
+    mediaQuery.addEventListener('change', handleChange);
+    return () => mediaQuery.removeEventListener('change', handleChange);
   }, []);
 
   useEffect(() => {