/* ============================================
   STABLE LANDING PAGE — Design System
   ============================================ */

/* CSS Variables — Theme Tokens */
:root {
  --font-sans: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', Consolas, monospace;

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
  --radius-full: 9999px;
}

/* Dark Theme (Default) */
[data-theme="dark"] {
  --bg-body: #070709;
  --bg-surface: #0f0f14;
  --bg-surface-rgb: 15, 15, 20;
  --bg-surface-elevated: #16161d;
  --bg-card: #13131a;
  --bg-card-hover: #1a1a24;
  --bg-terminal: #0d0d12;
  --bg-code: #0a0a0f;

  --text-primary: #f0f0f5;
  --text-secondary: #8a8a9a;
  --text-tertiary: #5a5a6a;
  --text-muted: #4a4a5a;
  --text-inverse: #0a0a0f;

  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-medium: rgba(255, 255, 255, 0.1);
  --border-strong: rgba(255, 255, 255, 0.15);

  --accent: #6366f1;
  --accent-light: #818cf8;
  --accent-dark: #4f46e5;
  --accent-glow: rgba(99, 102, 241, 0.3);

  --success: #22c55e;
  --warning: #f59e0b;
  --error: #ef4444;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.4);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.5);
  --shadow-lg: 0 12px 40px rgba(0,0,0,0.6);
  --shadow-glow: 0 0 40px var(--accent-glow);

  --gradient-hero: radial-gradient(ellipse 80% 50% at 50% -10%, rgba(99, 102, 241, 0.12), transparent),
                    radial-gradient(ellipse 60% 40% at 80% 60%, rgba(139, 92, 246, 0.06), transparent);
  --gradient-surface: linear-gradient(180deg, rgba(255,255,255,0.03) 0%, transparent 100%);
}

/* Light Theme */
[data-theme="light"] {
  --bg-body: #fafafa;
  --bg-surface: #ffffff;
  --bg-surface-rgb: 255, 255, 255;
  --bg-surface-elevated: #f5f5f7;
  --bg-card: #ffffff;
  --bg-card-hover: #f0f0f5;
  --bg-terminal: #1e1e2e;
  --bg-code: #f4f4f7;

  --text-primary: #111118;
  --text-secondary: #5a5a6a;
  --text-tertiary: #8a8a9a;
  --text-muted: #b0b0bd;
  --text-inverse: #ffffff;

  --border-subtle: rgba(0, 0, 0, 0.06);
  --border-medium: rgba(0, 0, 0, 0.1);
  --border-strong: rgba(0, 0, 0, 0.15);

  --accent: #4f46e5;
  --accent-light: #6366f1;
  --accent-dark: #4338ca;
  --accent-glow: rgba(79, 70, 229, 0.15);

  --success: #16a34a;
  --warning: #d97706;
  --error: #dc2626;

  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.1);
  --shadow-lg: 0 12px 48px rgba(0,0,0,0.12);
  --shadow-glow: 0 0 30px var(--accent-glow);

  --gradient-hero: radial-gradient(ellipse 80% 50% at 50% -10%, rgba(99, 102, 241, 0.08), transparent),
                    radial-gradient(ellipse 60% 40% at 80% 60%, rgba(139, 92, 246, 0.04), transparent);
  --gradient-surface: linear-gradient(180deg, rgba(0,0,0,0.01) 0%, transparent 100%);
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-body);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  transition: background 0.3s ease, color 0.3s ease;
}

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

a {
  color: var(--accent-light);
  text-decoration: none;
  transition: opacity 0.2s;
}

a:hover {
  opacity: 0.8;
}

/* ============================================
   ANIMATIONS
   ============================================ */

@keyframes fadeInUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes float {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-10px); }
}

@keyframes pulse-glow {
  0%, 100% { box-shadow: 0 0 20px var(--accent-glow); }
  50% { box-shadow: 0 0 40px var(--accent-glow), 0 0 60px var(--accent-glow); }
}

@keyframes gradient-shift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

.animate-fade-in-up {
  opacity: 0;
  animation: fadeInUp 0.8s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.animate-fade-in {
  opacity: 0;
  animation: fadeIn 1s ease forwards;
}

.delay-100 { animation-delay: 0.1s; }
.delay-200 { animation-delay: 0.2s; }
.delay-300 { animation-delay: 0.3s; }
.delay-400 { animation-delay: 0.4s; }
.delay-500 { animation-delay: 0.5s; }
.delay-600 { animation-delay: 0.6s; }

/* ============================================
   LAYOUT UTILITIES
   ============================================ */

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
}

.section {
  padding: 100px 0;
  position: relative;
}

.section-header {
  text-align: center;
  max-width: 640px;
  margin: 0 auto 64px;
}

/* ============================================
   NAVIGATION
   ============================================ */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 16px 0;
  transition: background 0.3s, backdrop-filter 0.3s, box-shadow 0.3s;
}

.nav--scrolled {
  background: rgba(var(--bg-surface-rgb, 15, 15, 20), 0.8);
  backdrop-filter: blur(20px) saturate(1.4);
  -webkit-backdrop-filter: blur(20px) saturate(1.4);
  border-bottom: 1px solid var(--border-subtle);
}

[data-theme="light"] .nav--scrolled {
  background: rgba(255, 255, 255, 0.85);
}

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

.nav__logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  font-size: 1.25rem;
  color: var(--text-primary);
  letter-spacing: -0.02em;
}

.nav__logo-mark {
  width: 32px;
  height: 32px;
  background: var(--accent);
  border-radius: var(--radius-md);
  display: grid;
  place-items: center;
  font-family: var(--font-mono);
  font-size: 0.875rem;
  font-weight: 700;
  color: white;
  box-shadow: 0 2px 8px var(--accent-glow);
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav__link {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-secondary);
  transition: color 0.2s;
}

.nav__link:hover {
  color: var(--text-primary);
  opacity: 1;
}

.nav__actions {
  display: flex;
  align-items: center;
  gap: 16px;
}

/* Theme Toggle */
.theme-toggle {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-full);
  border: 1px solid var(--border-medium);
  background: var(--bg-surface-elevated);
  color: var(--text-secondary);
  cursor: pointer;
  display: grid;
  place-items: center;
  transition: all 0.2s;
}

.theme-toggle:hover {
  background: var(--bg-card-hover);
  color: var(--text-primary);
  border-color: var(--border-strong);
}

.theme-toggle svg {
  width: 18px;
  height: 18px;
}

[data-theme="dark"] .theme-toggle .sun-icon { display: block; }
[data-theme="dark"] .theme-toggle .moon-icon { display: none; }
[data-theme="light"] .theme-toggle .sun-icon { display: none; }
[data-theme="light"] .theme-toggle .moon-icon { display: block; }

/* ============================================
   BUTTONS
   ============================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 20px;
  font-family: var(--font-sans);
  font-size: 0.875rem;
  font-weight: 600;
  border-radius: var(--radius-full);
  border: 1px solid transparent;
  cursor: pointer;
  transition: all 0.2s;
  white-space: nowrap;
}

.btn--primary {
  background: var(--accent);
  color: white;
  box-shadow: 0 2px 8px var(--accent-glow);
}

.btn--primary:hover {
  background: var(--accent-light);
  transform: translateY(-1px);
  box-shadow: 0 4px 16px var(--accent-glow);
  opacity: 1;
}

.btn--secondary {
  background: var(--bg-surface-elevated);
  color: var(--text-primary);
  border-color: var(--border-medium);
}

.btn--secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-strong);
  opacity: 1;
}

.btn--ghost {
  background: transparent;
  color: var(--text-secondary);
  border-color: var(--border-medium);
}

.btn--ghost:hover {
  background: var(--bg-surface-elevated);
  color: var(--text-primary);
  opacity: 1;
}

.btn--large {
  padding: 14px 28px;
  font-size: 1rem;
}

/* ============================================
   HERO SECTION
   ============================================ */

.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 140px 24px 80px;
  position: relative;
  overflow: hidden;
  background: var(--gradient-hero);
}

.hero__badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-medium);
  border-radius: var(--radius-full);
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 32px;
}

.hero__badge-dot {
  width: 6px;
  height: 6px;
  background: var(--success);
  border-radius: var(--radius-full);
  box-shadow: 0 0 8px var(--success);
}

.hero__title {
  font-size: clamp(2.5rem, 6vw, 4.5rem);
  font-weight: 900;
  line-height: 1.05;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
  background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero__title-accent {
  background: linear-gradient(135deg, var(--accent-light) 0%, #a78bfa 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero__subtitle {
  font-size: clamp(1.0625rem, 2vw, 1.25rem);
  color: var(--text-secondary);
  max-width: 560px;
  margin: 0 auto 40px;
  line-height: 1.6;
}

.hero__actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 64px;
}

.hero__meta {
  display: flex;
  gap: 24px;
  justify-content: center;
  flex-wrap: wrap;
  font-size: 0.8125rem;
  color: var(--text-tertiary);
}

.hero__meta-item {
  display: flex;
  align-items: center;
  gap: 6px;
}

.hero__meta-item svg {
  width: 16px;
  height: 16px;
  color: var(--text-muted);
}

/* Hero Visual */
.hero__visual {
  position: relative;
  width: 100%;
  max-width: 960px;
  margin-top: 20px;
}

/* ============================================
   TERMINAL MOCKUP
   ============================================ */

.terminal {
  background: var(--bg-terminal);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-medium);
  overflow: hidden;
  box-shadow: var(--shadow-lg), 0 0 80px rgba(0,0,0,0.3);
  font-family: var(--font-mono);
  text-align: left;
}

.terminal__header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 18px;
  background: rgba(255,255,255,0.02);
  border-bottom: 1px solid var(--border-subtle);
}

.terminal__dot {
  width: 12px;
  height: 12px;
  border-radius: var(--radius-full);
}

.terminal__dot--red { background: #ff5f56; }
.terminal__dot--yellow { background: #ffbd2e; }
.terminal__dot--green { background: #27c93f; }

.terminal__title {
  margin-left: 8px;
  font-size: 0.75rem;
  color: var(--text-muted);
  font-family: var(--font-sans);
}

.terminal__body {
  padding: 20px 24px;
  font-size: 0.8125rem;
  line-height: 1.7;
  color: #c8c8d0;
  overflow-x: auto;
}

.terminal__prompt {
  color: var(--accent-light);
}

.terminal__cmd {
  color: var(--text-primary);
}

.terminal__output {
  color: var(--text-secondary);
}

.terminal__success {
  color: var(--success);
}

/* ============================================
   BROWSER / APP MOCKUP
   ============================================ */

.browser {
  background: var(--bg-surface);
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-medium);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
}

.browser__header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  background: var(--gradient-surface);
  border-bottom: 1px solid var(--border-subtle);
}

.browser__dot {
  width: 10px;
  height: 10px;
  border-radius: var(--radius-full);
}

.browser__dot--red { background: #ff5f56; }
.browser__dot--yellow { background: #ffbd2e; }
.browser__dot--green { background: #27c93f; }

.browser__url {
  flex: 1;
  margin-left: 12px;
  padding: 4px 12px;
  background: var(--bg-body);
  border-radius: var(--radius-sm);
  font-size: 0.6875rem;
  color: var(--text-muted);
  font-family: var(--font-mono);
  text-align: center;
}

.browser__body img {
  width: 100%;
  display: block;
}

/* ============================================
   SCREENSHOT GRID
   ============================================ */

.gallery {
  display: grid;
  gap: 24px;
}

.gallery--2 {
  grid-template-columns: repeat(2, 1fr);
}

.gallery--3 {
  grid-template-columns: repeat(3, 1fr);
}

.gallery--feature {
  grid-template-columns: 1.2fr 1fr;
  align-items: start;
}

.gallery__item {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
  border: 1px solid var(--border-subtle);
  transition: transform 0.3s, box-shadow 0.3s;
}

.gallery__item:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
}

.gallery__item img {
  width: 100%;
  height: auto;
  object-fit: cover;
  transition: transform 0.5s cubic-bezier(0.16, 1, 0.3, 1);
}

.gallery__item:hover img {
  transform: scale(1.03);
}

.gallery__caption {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 20px;
  background: linear-gradient(transparent, rgba(0,0,0,0.8));
  color: white;
}

.gallery__caption-title {
  font-size: 0.875rem;
  font-weight: 600;
  margin-bottom: 2px;
}

.gallery__caption-desc {
  font-size: 0.75rem;
  opacity: 0.7;
}

/* ============================================
   FEATURE CARDS
   ============================================ */

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 20px;
}

.feature-card {
  padding: 32px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  transition: all 0.3s;
}

.feature-card:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-medium);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.feature-card__icon {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-md);
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  display: grid;
  place-items: center;
  margin-bottom: 20px;
  color: var(--accent-light);
}

.feature-card__icon svg {
  width: 22px;
  height: 22px;
}

.feature-card__title {
  font-size: 1.0625rem;
  font-weight: 700;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.feature-card__desc {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ============================================
   SECTION VARIANTS
   ============================================ */

.section--gradient {
  background: var(--gradient-hero);
}

.section--surface {
  background: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
}

.section__label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent-light);
  margin-bottom: 16px;
}

.section__title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.section__subtitle {
  font-size: 1.0625rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ============================================
   CLI SHOWCASE
   ============================================ */

.cli-showcase {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: center;
}

.cli-showcase__content {
  order: 1;
}

.cli-showcase__visual {
  order: 2;
}

.cli-showcase__commands {
  margin-top: 24px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.cli-command {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  background: var(--bg-code);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
}

.cli-command__prompt {
  color: var(--accent-light);
  font-weight: 600;
}

.cli-command__text {
  color: var(--text-secondary);
}

/* ============================================
   DOWNLOAD / CTA SECTION
   ============================================ */

.cta-box {
  padding: 64px;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-xl);
  text-align: center;
  position: relative;
  overflow: hidden;
}

.cta-box::before {
  content: '';
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 60%;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--accent), transparent);
}

.cta-box__title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 800;
  margin-bottom: 12px;
}

.cta-box__desc {
  color: var(--text-secondary);
  margin-bottom: 32px;
  max-width: 480px;
  margin-left: auto;
  margin-right: auto;
}

.download-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
  max-width: 480px;
  margin: 0 auto;
}

.download-card {
  padding: 24px;
  background: var(--bg-surface-elevated);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  text-align: center;
  transition: all 0.2s;
}

.download-card:hover {
  border-color: var(--border-medium);
  transform: translateY(-2px);
}

.download-card__icon {
  width: 48px;
  height: 48px;
  margin: 0 auto 12px;
  color: var(--text-secondary);
}

.download-card__title {
  font-size: 0.9375rem;
  font-weight: 700;
  margin-bottom: 4px;
  color: var(--text-primary);
}

.download-card__meta {
  font-size: 0.75rem;
  color: var(--text-tertiary);
  margin-bottom: 16px;
}

/* ============================================
   FOOTER
   ============================================ */

.footer {
  padding: 48px 0;
  border-top: 1px solid var(--border-subtle);
  text-align: center;
}

.footer__text {
  font-size: 0.8125rem;
  color: var(--text-tertiary);
}

/* ============================================
   SCROLL REVEAL
   ============================================ */

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1), transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ============================================
   RESPONSIVE
   ============================================ */

@media (max-width: 768px) {
  .section {
    padding: 64px 0;
  }

  .nav__links {
    display: none;
  }

  .hero {
    padding: 120px 20px 60px;
  }

  .cli-showcase {
    grid-template-columns: 1fr;
  }

  .cli-showcase__content {
    order: 2;
  }

  .cli-showcase__visual {
    order: 1;
  }

  .gallery--2,
  .gallery--3,
  .gallery--feature {
    grid-template-columns: 1fr;
  }

  .download-grid {
    grid-template-columns: 1fr;
  }

  .cta-box {
    padding: 40px 24px;
  }

  .features-grid {
    grid-template-columns: 1fr;
  }
}

/* ============================================
   ACCESSIBILITY
   ============================================ */

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
  html {
    scroll-behavior: auto;
  }
}