/* ============================================
   CHAMI - Design System & Styles
   Modern, Youthful Social App Landing Page
   ============================================ */

/* -------------------- CSS Variables -------------------- */
:root {
  /* Primary Colors - Vibrant Gradient */
  --primary-purple: #8B5CF6;
  --primary-pink: #EC4899;
  --primary-orange: #F97316;
  
  /* Gradient Definitions */
  --gradient-primary: linear-gradient(135deg, #8B5CF6 0%, #EC4899 50%, #F97316 100%);
  --gradient-hero: linear-gradient(180deg, #0F0F1A 0%, #1A1A2E 50%, #16213E 100%);
  --gradient-card: linear-gradient(135deg, rgba(139, 92, 246, 0.1) 0%, rgba(236, 72, 153, 0.1) 100%);
  
  /* Background Colors */
  --bg-dark: #0A0A0F;
  --bg-darker: #050508;
  --bg-card: rgba(255, 255, 255, 0.03);
  --bg-glass: rgba(255, 255, 255, 0.05);
  
  /* Text Colors */
  --text-primary: #FFFFFF;
  --text-secondary: rgba(255, 255, 255, 0.7);
  --text-muted: rgba(255, 255, 255, 0.5);
  
  /* Borders */
  --border-glass: rgba(255, 255, 255, 0.1);
  --border-gradient: linear-gradient(135deg, rgba(139, 92, 246, 0.5) 0%, rgba(236, 72, 153, 0.5) 100%);
  
  /* Shadows */
  --shadow-glow: 0 0 60px rgba(139, 92, 246, 0.3);
  --shadow-card: 0 8px 32px rgba(0, 0, 0, 0.3);
  --shadow-button: 0 4px 20px rgba(139, 92, 246, 0.4);
  
  /* Typography */
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-display: 'Outfit', var(--font-primary);
  
  /* Spacing */
  --space-xs: 0.5rem;
  --space-sm: 1rem;
  --space-md: 1.5rem;
  --space-lg: 2rem;
  --space-xl: 3rem;
  --space-2xl: 5rem;
  --space-3xl: 8rem;
  
  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 20px;
  --radius-xl: 30px;
  --radius-full: 9999px;
  
  /* Transitions */
  --transition-fast: 0.15s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
  
  /* Container */
  --container-max: 1200px;
}

/* -------------------- Reset & Base -------------------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  font-family: var(--font-primary);
  background: var(--bg-dark);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition-fast);
}

img {
  max-width: 100%;
  height: auto;
  display: block;
}

ul, ol {
  list-style: none;
}

button {
  font-family: inherit;
  border: none;
  cursor: pointer;
  background: none;
}

/* -------------------- Typography -------------------- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.2;
}

h1 {
  font-size: clamp(2.5rem, 5vw + 1rem, 4.5rem);
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(2rem, 4vw, 3rem);
  letter-spacing: -0.01em;
}

h3 {
  font-size: clamp(1.25rem, 2vw, 1.5rem);
}

.gradient-text {
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* -------------------- Layout -------------------- */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--space-md);
}

section {
  padding: var(--space-3xl) 0;
  position: relative;
}

/* -------------------- Navigation -------------------- */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  padding: var(--space-sm) 0;
  transition: var(--transition-normal);
}

.nav.scrolled {
  background: rgba(10, 10, 15, 0.9);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-glass);
}

.nav-container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav-logo {
  font-family: var(--font-display);
  font-size: 1.75rem;
  font-weight: 800;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-lg);
}

.nav-links a {
  color: var(--text-secondary);
  font-weight: 500;
  font-size: 0.95rem;
  transition: var(--transition-fast);
}

.nav-links a:hover {
  color: var(--text-primary);
}

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  padding: 8px;
}

.nav-toggle span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 2px;
  transition: var(--transition-normal);
}

/* Mobile Menu */
@media (max-width: 768px) {
  .nav-toggle {
    display: flex;
  }
  
  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: var(--bg-darker);
    flex-direction: column;
    padding: var(--space-3xl) var(--space-lg);
    gap: var(--space-md);
    transition: var(--transition-normal);
    border-left: 1px solid var(--border-glass);
  }
  
  .nav-links.active {
    right: 0;
  }
  
  .nav-links a {
    font-size: 1.1rem;
  }
}

/* -------------------- Buttons -------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  padding: 0.875rem 1.75rem;
  font-size: 0.95rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  transition: var(--transition-normal);
}

.btn-primary {
  background: var(--gradient-primary);
  color: white;
  box-shadow: var(--shadow-button);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 30px rgba(139, 92, 246, 0.5);
}

.btn-secondary {
  background: var(--bg-glass);
  color: var(--text-primary);
  border: 1px solid var(--border-glass);
  backdrop-filter: blur(10px);
}

.btn-secondary:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: rgba(255, 255, 255, 0.2);
}

.btn-icon {
  width: 20px;
  height: 20px;
}

/* -------------------- Hero Section -------------------- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding-top: 80px;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 30% 30%, rgba(139, 92, 246, 0.15) 0%, transparent 50%),
              radial-gradient(circle at 70% 70%, rgba(236, 72, 153, 0.1) 0%, transparent 50%);
  animation: heroGlow 15s ease-in-out infinite alternate;
}

@keyframes heroGlow {
  0% { transform: translate(0, 0) rotate(0deg); }
  100% { transform: translate(-5%, -5%) rotate(10deg); }
}

.hero-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--space-2xl);
  align-items: center;
  position: relative;
  z-index: 1;
}

.hero-content {
  max-width: 600px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  padding: 0.5rem 1rem;
  background: var(--bg-glass);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-full);
  font-size: 0.875rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-md);
  backdrop-filter: blur(10px);
}

.hero-badge span {
  color: var(--primary-pink);
}

.hero-title {
  margin-bottom: var(--space-md);
}

.hero-subtitle {
  font-size: 1.25rem;
  color: var(--text-secondary);
  margin-bottom: var(--space-xl);
  max-width: 480px;
}

.hero-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

.hero-visual {
  position: relative;
  display: flex;
  justify-content: center;
  align-items: center;
}

.phone-mockup {
  position: relative;
  width: 280px;
  height: 580px;
  background: linear-gradient(180deg, #1a1a2e 0%, #0f0f1a 100%);
  border-radius: 40px;
  border: 3px solid rgba(255, 255, 255, 0.1);
  box-shadow: var(--shadow-glow), var(--shadow-card);
  overflow: hidden;
  animation: float 6s ease-in-out infinite;
}

@keyframes float {
  0%, 100% { transform: translateY(0px); }
  50% { transform: translateY(-20px); }
}

.phone-screen {
  position: absolute;
  top: 10px;
  left: 10px;
  right: 10px;
  bottom: 10px;
  background: var(--gradient-primary);
  border-radius: 32px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-sm);
}

.phone-screen-logo {
  font-family: var(--font-display);
  font-size: 2.5rem;
  font-weight: 800;
  color: white;
}

.phone-screen-tagline {
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.9);
}

/* Floating Elements */
.floating-elements {
  position: absolute;
  width: 100%;
  height: 100%;
  pointer-events: none;
}

.floating-bubble {
  position: absolute;
  border-radius: 50%;
  background: var(--gradient-primary);
  opacity: 0.3;
  filter: blur(1px);
  animation: bubbleFloat 8s ease-in-out infinite;
}

.floating-bubble:nth-child(1) {
  width: 60px;
  height: 60px;
  top: 10%;
  left: -10%;
  animation-delay: 0s;
}

.floating-bubble:nth-child(2) {
  width: 40px;
  height: 40px;
  top: 60%;
  right: -5%;
  animation-delay: 2s;
}

.floating-bubble:nth-child(3) {
  width: 30px;
  height: 30px;
  bottom: 20%;
  left: 5%;
  animation-delay: 4s;
}

@keyframes bubbleFloat {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(10px, -20px) scale(1.1); }
  66% { transform: translate(-10px, 10px) scale(0.9); }
}

@media (max-width: 968px) {
  .hero-container {
    grid-template-columns: 1fr;
    text-align: center;
  }
  
  .hero-content {
    max-width: 100%;
  }
  
  .hero-subtitle {
    max-width: 100%;
  }
  
  .hero-buttons {
    justify-content: center;
  }
  
  .hero-visual {
    order: -1;
  }
  
  .phone-mockup {
    width: 240px;
    height: 500px;
  }
}

/* -------------------- Features Section -------------------- */
.features {
  background: var(--bg-darker);
  position: relative;
}

.features::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--border-glass), transparent);
}

.section-header {
  text-align: center;
  max-width: 600px;
  margin: 0 auto var(--space-2xl);
}

.section-header p {
  color: var(--text-secondary);
  margin-top: var(--space-sm);
  font-size: 1.1rem;
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-lg);
}

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-lg);
  padding: var(--space-xl);
  transition: var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.feature-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--gradient-primary);
  transform: scaleX(0);
  transition: var(--transition-normal);
}

.feature-card:hover {
  transform: translateY(-5px);
  border-color: rgba(139, 92, 246, 0.3);
  background: var(--bg-glass);
}

.feature-card:hover::before {
  transform: scaleX(1);
}

.feature-icon {
  width: 56px;
  height: 56px;
  background: var(--gradient-primary);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  margin-bottom: var(--space-md);
}

.feature-card h3 {
  margin-bottom: var(--space-xs);
}

.feature-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

@media (max-width: 968px) {
  .features-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 640px) {
  .features-grid {
    grid-template-columns: 1fr;
  }
}

/* -------------------- App Preview Section -------------------- */
.preview {
  position: relative;
  overflow: hidden;
}

.preview::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 120%;
  height: 120%;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.08) 0%, transparent 60%);
}

.preview-container {
  position: relative;
  z-index: 1;
}

.preview-screens {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--space-lg);
  margin-top: var(--space-2xl);
  perspective: 1000px;
}

.preview-phone {
  width: 200px;
  height: 420px;
  background: linear-gradient(180deg, #1a1a2e 0%, #0f0f1a 100%);
  border-radius: 30px;
  border: 2px solid rgba(255, 255, 255, 0.1);
  box-shadow: var(--shadow-card);
  transition: var(--transition-slow);
  position: relative;
  overflow: hidden;
}

.preview-phone::after {
  content: '';
  position: absolute;
  top: 8px;
  left: 8px;
  right: 8px;
  bottom: 8px;
  border-radius: 24px;
  background: var(--gradient-card);
}

.preview-phone:nth-child(1) {
  transform: rotateY(15deg) translateZ(-50px) scale(0.85);
  opacity: 0.7;
}

.preview-phone:nth-child(2) {
  transform: translateZ(50px) scale(1.1);
  z-index: 2;
  box-shadow: var(--shadow-glow), var(--shadow-card);
}

.preview-phone:nth-child(3) {
  transform: rotateY(-15deg) translateZ(-50px) scale(0.85);
  opacity: 0.7;
}

.preview-phone-content {
  position: absolute;
  top: 8px;
  left: 8px;
  right: 8px;
  bottom: 8px;
  border-radius: 24px;
  display: flex;
  flex-direction: column;
  padding: var(--space-md);
  z-index: 1;
}

.preview-phone-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--space-sm);
}

.preview-phone-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--gradient-primary);
}

.preview-phone-stories {
  display: flex;
  gap: var(--space-xs);
  margin-bottom: var(--space-md);
}

.story-circle {
  width: 48px;
  height: 48px;
  border-radius: 50%;
  background: var(--gradient-primary);
  padding: 2px;
}

.story-circle-inner {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: var(--bg-dark);
  display: flex;
  align-items: center;
  justify-content: center;
}

.preview-phone-post {
  flex: 1;
  background: rgba(255, 255, 255, 0.03);
  border-radius: var(--radius-md);
  padding: var(--space-sm);
}

.post-header {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
  margin-bottom: var(--space-sm);
}

.post-avatar {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--primary-purple);
}

.post-name {
  font-size: 0.75rem;
  font-weight: 600;
}

.post-image {
  width: 100%;
  height: 100px;
  background: var(--gradient-primary);
  border-radius: var(--radius-sm);
  margin-bottom: var(--space-xs);
}

.post-actions {
  display: flex;
  gap: var(--space-sm);
  font-size: 0.7rem;
  color: var(--text-muted);
}

@media (max-width: 768px) {
  .preview-screens {
    gap: var(--space-sm);
  }
  
  .preview-phone {
    width: 140px;
    height: 300px;
  }
  
  .preview-phone:nth-child(1),
  .preview-phone:nth-child(3) {
    display: none;
  }
  
  .preview-phone:nth-child(2) {
    transform: none;
    width: 200px;
    height: 420px;
  }
}

/* -------------------- Stats Section -------------------- */
.stats {
  background: var(--bg-darker);
  border-top: 1px solid var(--border-glass);
  border-bottom: 1px solid var(--border-glass);
  padding: var(--space-2xl) 0;
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--space-lg);
  text-align: center;
}

.stat-item h3 {
  font-size: clamp(2rem, 4vw, 3rem);
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--space-xs);
}

.stat-item p {
  color: var(--text-secondary);
  font-size: 0.95rem;
}

@media (max-width: 768px) {
  .stats-grid {
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-xl);
  }
}

/* -------------------- Download Section -------------------- */
.download {
  position: relative;
  overflow: hidden;
}

.download-card {
  background: var(--gradient-card);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-xl);
  padding: var(--space-3xl);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.download-card::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 50% 0%, rgba(139, 92, 246, 0.1) 0%, transparent 50%);
}

.download-content {
  position: relative;
  z-index: 1;
}

.download-content h2 {
  margin-bottom: var(--space-sm);
}

.download-content p {
  color: var(--text-secondary);
  font-size: 1.1rem;
  margin-bottom: var(--space-xl);
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}

.download-buttons {
  display: flex;
  justify-content: center;
  gap: var(--space-md);
  flex-wrap: wrap;
}

.store-btn {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  padding: 0.875rem 1.5rem;
  background: var(--bg-glass);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-md);
  transition: var(--transition-normal);
}

.store-btn:hover {
  background: rgba(255, 255, 255, 0.1);
  transform: translateY(-2px);
}

.store-btn svg {
  width: 28px;
  height: 28px;
}

.store-btn-text {
  text-align: left;
}

.store-btn-text span {
  display: block;
  font-size: 0.7rem;
  color: var(--text-muted);
}

.store-btn-text strong {
  font-size: 1rem;
}

/* -------------------- Footer -------------------- */
.footer {
  background: var(--bg-darker);
  padding: var(--space-2xl) 0 var(--space-lg);
  border-top: 1px solid var(--border-glass);
}

.footer-content {
  display: grid;
  grid-template-columns: 2fr repeat(3, 1fr);
  gap: var(--space-2xl);
  margin-bottom: var(--space-2xl);
}

.footer-brand {
  max-width: 300px;
}

.footer-logo {
  font-family: var(--font-display);
  font-size: 2rem;
  font-weight: 800;
  background: var(--gradient-primary);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--space-sm);
}

.footer-brand p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  margin-bottom: var(--space-md);
}

.social-links {
  display: flex;
  gap: var(--space-sm);
}

.social-link {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-glass);
  border: 1px solid var(--border-glass);
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  transition: var(--transition-normal);
}

.social-link:hover {
  background: var(--gradient-primary);
  border-color: transparent;
  color: white;
}

.social-link svg {
  width: 20px;
  height: 20px;
}

.footer-column h4 {
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-bottom: var(--space-md);
}

.footer-column ul {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
}

.footer-column a {
  color: var(--text-secondary);
  font-size: 0.95rem;
  transition: var(--transition-fast);
}

.footer-column a:hover {
  color: var(--text-primary);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: var(--space-lg);
  border-top: 1px solid var(--border-glass);
}

.footer-bottom p {
  color: var(--text-muted);
  font-size: 0.875rem;
}

.footer-legal {
  display: flex;
  gap: var(--space-md);
}

.footer-legal a {
  color: var(--text-muted);
  font-size: 0.875rem;
}

.footer-legal a:hover {
  color: var(--text-secondary);
}

@media (max-width: 968px) {
  .footer-content {
    grid-template-columns: repeat(2, 1fr);
  }
  
  .footer-brand {
    grid-column: span 2;
  }
}

@media (max-width: 640px) {
  .footer-content {
    grid-template-columns: 1fr;
  }
  
  .footer-brand {
    grid-column: 1;
    text-align: center;
    max-width: 100%;
  }
  
  .social-links {
    justify-content: center;
  }
  
  .footer-column {
    text-align: center;
  }
  
  .footer-bottom {
    flex-direction: column;
    gap: var(--space-sm);
    text-align: center;
  }
}

/* -------------------- Animations -------------------- */
.fade-in {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

.fade-in-delay-1 { transition-delay: 0.1s; }
.fade-in-delay-2 { transition-delay: 0.2s; }
.fade-in-delay-3 { transition-delay: 0.3s; }
.fade-in-delay-4 { transition-delay: 0.4s; }
.fade-in-delay-5 { transition-delay: 0.5s; }
.fade-in-delay-6 { transition-delay: 0.6s; }

/* Smooth scrollbar */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-darker);
}

::-webkit-scrollbar-thumb {
  background: rgba(139, 92, 246, 0.5);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: rgba(139, 92, 246, 0.7);
}