/* ============================================================
   VoiceAI.Live — Global Design System
   Bilingual (CN/EN) · Bidding Demo Site
   ============================================================ */

:root {
  /* Core Palette - VoiceAI Signature */
  --bg-deep: #05050d;
  --bg-dark: #0a0a1a;
  --bg-panel: rgba(255, 255, 255, 0.04);
  --bg-panel-2: rgba(255, 255, 255, 0.07);
  
  --violet: #7c5cff;
  --violet-soft: #a78bfa;
  --cyan: #22e0ff;
  --cyan-soft: #67e8f9;
  --magenta: #ff4dd9;
  --magenta-soft: #f9a8d4;
  --lime: #9dff5b;
  --gold: #ffd76a;
  --teal: #5eead4;
  
  --text-primary: #eef0ff;
  --text-secondary: #a8acd8;
  --text-muted: #6b6f9c;
  --text-dim: #4a4e7a;
  
  --line: rgba(124, 92, 255, 0.22);
  --line-2: rgba(34, 224, 255, 0.18);
  --line-bright: rgba(124, 92, 255, 0.4);
  
  --glow-violet: 0 0 40px rgba(124, 92, 255, 0.45);
  --glow-cyan: 0 0 40px rgba(34, 224, 255, 0.4);
  --glow-magenta: 0 0 40px rgba(255, 77, 217, 0.35);
  
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-xl: 28px;
  
  --font-display: 'Orbitron', 'Noto Sans SC', sans-serif;
  --font-body: 'Sora', 'Noto Sans SC', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, monospace;
  
  --nav-height: 72px;
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  background: var(--bg-deep);
  color: var(--text-primary);
  overflow-x: hidden;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
}

/* Cosmic Background */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -2;
  background:
    radial-gradient(1200px 700px at 12% -5%, rgba(124, 92, 255, 0.20), transparent 60%),
    radial-gradient(1000px 650px at 95% 8%, rgba(34, 224, 255, 0.16), transparent 60%),
    radial-gradient(900px 700px at 50% 110%, rgba(255, 77, 217, 0.14), transparent 60%),
    var(--bg-deep);
}

body::after {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  opacity: 0.4;
  background-image: radial-gradient(rgba(255, 255, 255, 0.15) 1px, transparent 1.4px);
  background-size: 46px 46px;
  -webkit-mask-image: radial-gradient(ellipse at 50% 40%, #000 30%, transparent 75%);
  mask-image: radial-gradient(ellipse at 50% 40%, #000 30%, transparent 75%);
  pointer-events: none;
}

::selection {
  background: var(--violet);
  color: #fff;
}

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

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

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

/* ============ NAVIGATION ============ */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  height: var(--nav-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 40px;
  backdrop-filter: blur(16px);
  background: linear-gradient(180deg, rgba(5, 5, 13, 0.85), rgba(5, 5, 13, 0.6));
  border-bottom: 1px solid var(--line);
  transition: var(--transition);
}

.navbar.scrolled {
  background: rgba(5, 5, 13, 0.92);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}

.nav-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 18px;
  letter-spacing: 1.5px;
}

.nav-brand .logo-dot {
  width: 14px;
  height: 14px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  box-shadow: var(--glow-cyan);
  animation: pulse-dot 2.4s infinite;
}

@keyframes pulse-dot {
  0%, 100% { transform: scale(1); opacity: 1; }
  50% { transform: scale(1.35); opacity: 0.65; }
}

.nav-brand small {
  font-family: var(--font-body);
  font-weight: 300;
  letter-spacing: 1px;
  color: var(--text-muted);
  font-size: 10px;
  display: block;
  margin-top: -2px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
  list-style: none;
}

.nav-links > li {
  position: relative;
}

.nav-links > li > a {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 10px 16px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.nav-links > li > a:hover,
.nav-links > li > a.active {
  color: var(--text-primary);
  background: var(--bg-panel);
}

.nav-links > li > a .chev {
  font-size: 10px;
  transition: transform 0.2s;
}

.nav-links > li:hover > a .chev {
  transform: rotate(180deg);
}

/* Dropdown */
.dropdown {
  position: absolute;
  top: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%) translateY(8px);
  min-width: 240px;
  padding: 8px;
  background: rgba(10, 10, 26, 0.95);
  backdrop-filter: blur(20px);
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.5);
  opacity: 0;
  visibility: hidden;
  transition: all 0.25s ease;
}

.nav-links > li:hover .dropdown {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}

.dropdown a {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  font-size: 13px;
  color: var(--text-secondary);
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.dropdown a:hover {
  background: var(--bg-panel-2);
  color: var(--text-primary);
}

.dropdown a .icon {
  width: 32px;
  height: 32px;
  border-radius: 8px;
  display: grid;
  place-items: center;
  font-size: 14px;
  background: var(--bg-panel-2);
}

.dropdown a .label {
  font-weight: 500;
}

.dropdown a .desc {
  font-size: 11px;
  color: var(--text-muted);
  display: block;
}

/* Nav Right */
.nav-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

.lang-toggle {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 6px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--bg-panel);
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  transition: var(--transition);
}

.lang-toggle:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

.lang-toggle .dot-lang {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--lime);
  box-shadow: 0 0 8px var(--lime);
}

.btn-primary {
  padding: 10px 22px;
  border-radius: 999px;
  background: linear-gradient(100deg, var(--violet), var(--magenta));
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  box-shadow: var(--glow-violet);
  transition: var(--transition);
}

.btn-primary:hover {
  transform: translateY(-2px);
  filter: brightness(1.1);
}

.btn-ghost {
  padding: 10px 22px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--bg-panel);
  color: var(--text-primary);
  font-size: 13px;
  font-weight: 500;
  transition: var(--transition);
}

.btn-ghost:hover {
  border-color: var(--cyan);
  box-shadow: var(--glow-cyan);
}

/* Mobile menu button */
.mobile-menu-btn {
  display: none;
  width: 40px;
  height: 40px;
  border-radius: 10px;
  border: 1px solid var(--line);
  background: var(--bg-panel);
  color: var(--text-primary);
  font-size: 20px;
}

/* ============ HERO SECTION ============ */
.hero {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: calc(var(--nav-height) + 40px) 24px 80px;
  position: relative;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 18px;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  background: var(--bg-panel);
  font-size: 12px;
  color: var(--cyan-soft);
  margin-bottom: 28px;
  font-weight: 500;
}

.hero-badge .pulse {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--lime);
  box-shadow: 0 0 12px var(--lime);
  animation: pulse-dot 1.6s infinite;
}

.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(36px, 6vw, 72px);
  font-weight: 900;
  line-height: 1.1;
  letter-spacing: 2px;
  margin-bottom: 20px;
  background: linear-gradient(135deg, #fff 0%, var(--violet-soft) 50%, var(--cyan) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero h1 .accent {
  display: block;
  background: linear-gradient(90deg, var(--cyan), var(--magenta));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-subtitle {
  font-size: clamp(15px, 2vw, 19px);
  color: var(--text-secondary);
  max-width: 680px;
  margin-bottom: 40px;
  line-height: 1.7;
}

.hero-cta {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
  margin-bottom: 60px;
}

.hero-stats {
  display: flex;
  gap: 48px;
  flex-wrap: wrap;
  justify-content: center;
}

.stat-item {
  text-align: center;
}

.stat-num {
  font-family: var(--font-display);
  font-size: 32px;
  font-weight: 900;
  background: linear-gradient(135deg, var(--violet-soft), var(--cyan));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.stat-label {
  font-size: 12px;
  color: var(--text-muted);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-top: 4px;
}

/* ============ SECTION STYLES ============ */
section {
  padding: 100px 40px;
  position: relative;
}

.section-header {
  text-align: center;
  margin-bottom: 60px;
}

.section-tag {
  display: inline-block;
  padding: 6px 14px;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--cyan);
  margin-bottom: 16px;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(28px, 4vw, 44px);
  font-weight: 800;
  letter-spacing: 1px;
  margin-bottom: 16px;
}

.section-desc {
  font-size: 16px;
  color: var(--text-secondary);
  max-width: 640px;
  margin: 0 auto;
  line-height: 1.7;
}

/* ============ PRODUCT GRID ============ */
.product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 24px;
  max-width: 1280px;
  margin: 0 auto;
}

.product-card {
  position: relative;
  padding: 32px;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  background: var(--bg-panel);
  backdrop-filter: blur(10px);
  transition: var(--transition);
  overflow: hidden;
}

.product-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--violet), var(--cyan), transparent);
  opacity: 0;
  transition: var(--transition);
}

.product-card:hover {
  border-color: var(--line-bright);
  transform: translateY(-6px);
  box-shadow: 0 20px 60px rgba(124, 92, 255, 0.15);
}

.product-card:hover::before {
  opacity: 1;
}

.product-icon {
  width: 56px;
  height: 56px;
  border-radius: 14px;
  display: grid;
  place-items: center;
  font-size: 24px;
  margin-bottom: 20px;
  background: linear-gradient(135deg, rgba(124, 92, 255, 0.2), rgba(34, 224, 255, 0.1));
  border: 1px solid var(--line);
}

.product-card h3 {
  font-family: var(--font-display);
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.5px;
  margin-bottom: 10px;
}

.product-card .product-sub {
  font-size: 12px;
  color: var(--cyan-soft);
  font-weight: 500;
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 14px;
}

.product-card p {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 20px;
}

.product-features {
  list-style: none;
  margin-bottom: 24px;
}

.product-features li {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 6px 0;
  font-size: 13px;
  color: var(--text-secondary);
}

.product-features li::before {
  content: "✦";
  color: var(--cyan);
  font-size: 10px;
}

.product-card .card-actions {
  display: flex;
  gap: 10px;
}

.btn-card {
  flex: 1;
  padding: 10px 16px;
  border-radius: 10px;
  font-size: 12px;
  font-weight: 600;
  text-align: center;
  transition: var(--transition);
}

.btn-card.primary {
  background: linear-gradient(100deg, var(--violet), var(--magenta));
  color: #fff;
}

.btn-card.primary:hover {
  filter: brightness(1.15);
}

.btn-card.secondary {
  border: 1px solid var(--line);
  background: var(--bg-panel-2);
  color: var(--text-secondary);
}

.btn-card.secondary:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

/* Product category colors */
.product-card.voiceai .product-icon { background: linear-gradient(135deg, rgba(124, 92, 255, 0.25), rgba(34, 224, 255, 0.15)); }
.product-card.exis .product-icon { background: linear-gradient(135deg, rgba(94, 234, 212, 0.2), rgba(45, 212, 191, 0.1)); }
.product-card.rockit .product-icon { background: linear-gradient(135deg, rgba(255, 165, 0, 0.2), rgba(255, 100, 0, 0.1)); }
.product-card.vesper .product-icon { background: linear-gradient(135deg, rgba(167, 139, 250, 0.2), rgba(94, 234, 212, 0.1)); }
.product-card.chip .product-icon { background: linear-gradient(135deg, rgba(59, 130, 246, 0.2), rgba(147, 51, 234, 0.1)); }
.product-card.game .product-icon { background: linear-gradient(135deg, rgba(236, 72, 153, 0.2), rgba(249, 115, 22, 0.1)); }
.product-card.model .product-icon { background: linear-gradient(135deg, rgba(16, 185, 129, 0.2), rgba(59, 130, 246, 0.1)); }

/* ============ FEATURES SECTION ============ */
.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 20px;
  max-width: 1200px;
  margin: 0 auto;
}

.feature-item {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: var(--bg-panel);
  transition: var(--transition);
}

.feature-item:hover {
  border-color: var(--line-2);
  background: var(--bg-panel-2);
  transform: translateY(-4px);
}

.feature-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  display: grid;
  place-items: center;
  font-size: 20px;
  background: linear-gradient(135deg, rgba(124, 92, 255, 0.2), rgba(34, 224, 255, 0.1));
  margin-bottom: 16px;
}

.feature-item h4 {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
}

.feature-item p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* ============ DEMO SHOWCASE ============ */
.demo-showcase {
  max-width: 1200px;
  margin: 0 auto;
}

.demo-tabs {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-bottom: 32px;
  flex-wrap: wrap;
}

.demo-tab {
  padding: 10px 20px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: var(--bg-panel);
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 500;
  transition: var(--transition);
}

.demo-tab:hover,
.demo-tab.active {
  border-color: var(--violet);
  background: rgba(124, 92, 255, 0.15);
  color: var(--text-primary);
}

.demo-preview {
  position: relative;
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: var(--bg-dark);
  aspect-ratio: 16 / 9;
}

.demo-browser-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  background: rgba(0, 0, 0, 0.3);
  border-bottom: 1px solid var(--line);
}

.demo-dots {
  display: flex;
  gap: 6px;
}

.demo-dots span {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--text-dim);
}

.demo-dots span:nth-child(1) { background: #ff5f57; }
.demo-dots span:nth-child(2) { background: #febc2e; }
.demo-dots span:nth-child(3) { background: #28c840; }

.demo-url {
  flex: 1;
  margin: 0 16px;
  padding: 6px 14px;
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.05);
  font-size: 11px;
  color: var(--text-muted);
  font-family: var(--font-mono);
  text-align: center;
}

.demo-content {
  padding: 32px;
  height: calc(100% - 48px);
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, var(--bg-dark), var(--bg-deep));
}

.demo-mock {
  width: 100%;
  height: 100%;
  border-radius: 8px;
  background: 
    linear-gradient(90deg, rgba(124, 92, 255, 0.1) 1px, transparent 1px),
    linear-gradient(rgba(124, 92, 255, 0.1) 1px, transparent 1px),
    var(--bg-panel);
  background-size: 20px 20px;
  border: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 16px;
}

.demo-mock-icon {
  font-size: 48px;
  animation: float 3s ease-in-out infinite;
}

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

.demo-mock h4 {
  font-family: var(--font-display);
  font-size: 20px;
  letter-spacing: 1px;
}

.demo-mock p {
  font-size: 13px;
  color: var(--text-muted);
}

/* ============ FOOTER ============ */
footer {
  padding: 60px 40px 30px;
  border-top: 1px solid var(--line);
  background: rgba(5, 5, 13, 0.8);
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
  gap: 40px;
  max-width: 1280px;
  margin: 0 auto 40px;
}

.footer-brand {
  max-width: 320px;
}

.footer-brand h3 {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 900;
  letter-spacing: 2px;
  margin-bottom: 12px;
}

.footer-brand p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.7;
}

.footer-col h5 {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 16px;
}

.footer-col ul {
  list-style: none;
}

.footer-col li {
  margin-bottom: 10px;
}

.footer-col a {
  font-size: 13px;
  color: var(--text-secondary);
  transition: var(--transition);
}

.footer-col a:hover {
  color: var(--cyan);
}

.footer-bottom {
  max-width: 1280px;
  margin: 0 auto;
  padding-top: 24px;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
}

.footer-bottom p {
  font-size: 12px;
  color: var(--text-muted);
}

.footer-social {
  display: flex;
  gap: 12px;
}

.footer-social a {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  display: grid;
  place-items: center;
  border: 1px solid var(--line);
  background: var(--bg-panel);
  font-size: 14px;
  transition: var(--transition);
}

.footer-social a:hover {
  border-color: var(--cyan);
  color: var(--cyan);
}

/* ============ RESPONSIVE ============ */
@media (max-width: 1024px) {
  .nav-links {
    display: none;
  }
  
  .mobile-menu-btn {
    display: grid;
    place-items: center;
  }
  
  .footer-grid {
    grid-template-columns: 1fr 1fr 1fr;
  }
  
  .footer-brand {
    grid-column: 1 / -1;
    max-width: 100%;
  }
}

@media (max-width: 768px) {
  .navbar {
    padding: 0 20px;
  }
  
  section {
    padding: 60px 20px;
  }
  
  .hero-stats {
    gap: 24px;
  }
  
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  
  .product-grid {
    grid-template-columns: 1fr;
  }
  
  .hero-cta {
    flex-direction: column;
    width: 100%;
    max-width: 300px;
  }
  
  .hero-cta .btn-primary,
  .hero-cta .btn-ghost {
    width: 100%;
    text-align: center;
  }
}

@media (max-width: 480px) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
  
  .nav-right .btn-primary {
    display: none;
  }
}

/* ============ ANIMATIONS ============ */
.reveal {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}

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

/* Stagger delays */
.reveal:nth-child(1) { transition-delay: 0.05s; }
.reveal:nth-child(2) { transition-delay: 0.1s; }
.reveal:nth-child(3) { transition-delay: 0.15s; }
.reveal:nth-child(4) { transition-delay: 0.2s; }
.reveal:nth-child(5) { transition-delay: 0.25s; }
.reveal:nth-child(6) { transition-delay: 0.3s; }