/* ==========================================================================
   AirTone Studio · Official Site
   Design tokens reused from apps/web/src/styles/index.css
   Sony Industrial Design Style · Amber #f59e0b
   ========================================================================== */

:root {
  --bg-primary:     #0b0b0d;
  --bg-secondary:   #141418;
  --bg-tertiary:    #1b1b21;
  --bg-elevated:    #23232c;
  --bg-hover:       rgba(245, 158, 11, 0.08);

  --border-primary: #2a2a33;
  --border-secondary: #1f1f27;
  --border-accent:  #f59e0b;

  --fg-primary:     #f5f5f7;
  --fg-secondary:   #bcbcc5;
  --fg-muted:       #7a7a85;
  --fg-disabled:    #4b4b54;

  --accent:         #f59e0b;
  --accent-weak:    rgba(245, 158, 11, 0.18);
  --accent-strong:  #fbbf24;

  --glow: 0 0 24px -6px rgba(245, 158, 11, 0.55);

  --font-sans: "Inter", system-ui, -apple-system, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "SFMono-Regular", monospace;

  --radius-sm: 2px;
  --radius-md: 6px;
  --radius-lg: 10px;
  --radius-xl: 14px;

  --container: 1180px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  font-family: var(--font-sans);
  background-color: var(--bg-primary);
  color: var(--fg-primary);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  background-image:
    radial-gradient(1200px 500px at -10% -10%, var(--accent-weak), transparent 60%),
    radial-gradient(800px 400px at 110% 110%, var(--accent-weak), transparent 60%);
  background-size: auto, auto;
  background-attachment: fixed;
}

a {
  color: inherit;
  text-decoration: none;
}

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

::selection {
  background: var(--accent);
  color: #000;
}

::-webkit-scrollbar { width: 10px; height: 10px; }
::-webkit-scrollbar-thumb { background: var(--fg-muted); border-radius: 4px; }
::-webkit-scrollbar-track { background: transparent; }

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

.mono {
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

/* --------------------------------------------------------------------------
   Header / Nav
   -------------------------------------------------------------------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(11, 11, 13, 0.82);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--border-primary);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.brand .logo-mark {
  width: 34px;
  height: 34px;
  flex: none;
}

.brand-name {
  font-size: 16px;
}

.brand-name span {
  color: var(--fg-muted);
  font-weight: 400;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-links a {
  padding: 8px 14px;
  border-radius: var(--radius-md);
  font-size: 14px;
  color: var(--fg-secondary);
  transition: color 0.15s, background 0.15s;
}

.nav-links a:hover {
  color: var(--fg-primary);
  background: var(--bg-hover);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

/* Language switcher */
.lang-switcher {
  display: flex;
  align-items: center;
  gap: 2px;
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-md);
  padding: 2px;
}

.lang-btn {
  border: none;
  background: transparent;
  color: var(--fg-muted);
  font-family: var(--font-mono);
  font-size: 12px;
  padding: 6px 10px;
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: color 0.15s, background 0.15s;
  white-space: nowrap;
}

.lang-btn:hover {
  color: var(--fg-primary);
}

.lang-btn.active {
  color: #0b0b0d;
  background: var(--accent);
  font-weight: 500;
}

/* Hamburger */
.nav-toggle {
  display: none;
  border: 1px solid var(--border-primary);
  background: transparent;
  color: var(--fg-primary);
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  cursor: pointer;
  align-items: center;
  justify-content: center;
}

/* --------------------------------------------------------------------------
   Buttons
   -------------------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border-radius: var(--radius-md);
  padding: 12px 22px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: filter 0.15s, box-shadow 0.15s, border-color 0.15s, color 0.15s, background 0.15s;
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--accent);
  color: #0b0b0d;
}

.btn-primary:hover {
  filter: brightness(1.08);
  box-shadow: var(--glow);
}

.btn-ghost {
  border-color: var(--border-primary);
  color: var(--fg-secondary);
}

.btn-ghost:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: var(--bg-hover);
}

.btn-block {
  width: 100%;
}

/* --------------------------------------------------------------------------
   Hero
   -------------------------------------------------------------------------- */
.hero {
  padding: 96px 0 72px;
  border-bottom: 1px solid var(--border-primary);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 56px;
  align-items: center;
}

.eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.22em;
  color: var(--accent);
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 20px;
}

.eyebrow::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--accent);
}

.hero h1 {
  font-size: clamp(38px, 5.4vw, 64px);
  line-height: 1.05;
  font-weight: 600;
  letter-spacing: -0.03em;
  margin-bottom: 24px;
}

.hero h1 .accent {
  color: var(--accent);
}

.hero-desc {
  font-size: 17px;
  color: var(--fg-secondary);
  max-width: 560px;
  margin-bottom: 32px;
}

.hero-cta {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 32px;
}

.hero-chips {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-md);
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--fg-muted);
}

.chip-accent {
  color: var(--accent);
  border-color: var(--accent);
  background: var(--accent-weak);
}

/* Hero visual (device mock) */
.hero-visual {
  position: relative;
}

.device {
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-xl);
  background: var(--bg-secondary);
  overflow: hidden;
  box-shadow: 0 30px 80px -40px rgba(0, 0, 0, 0.9);
}

.device-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 14px 18px;
  border-bottom: 1px solid var(--border-primary);
}

.dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--fg-disabled);
}

.dot:nth-child(1) { background: #f43f5e; }
.dot:nth-child(2) { background: #f59e0b; }
.dot:nth-child(3) { background: #10b981; }

.device-bar .title {
  margin-left: 8px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--fg-muted);
}

.device-body {
  padding: 40px 32px;
  display: flex;
  flex-direction: column;
  gap: 18px;
}

.device-logo {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 18px;
  padding: 16px 0;
}

.device-logo .logo-mark {
  width: 88px;
  height: 88px;
}

.device-logo .name {
  font-size: 22px;
  font-weight: 600;
  letter-spacing: -0.01em;
}

.device-module {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-md);
  background: var(--bg-tertiary);
}

.device-module .m-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--fg-secondary);
}

.device-module .m-badge {
  font-family: var(--font-mono);
  font-size: 10px;
  padding: 3px 8px;
  border-radius: 999px;
  color: var(--accent);
  border: 1px solid var(--accent);
  background: var(--accent-weak);
}

/* --------------------------------------------------------------------------
   Sections (generic)
   -------------------------------------------------------------------------- */
.section {
  padding: 96px 0;
  border-bottom: 1px solid var(--border-primary);
}

.section-head {
  max-width: 640px;
  margin-bottom: 56px;
}

.section-head .eyebrow {
  color: var(--fg-muted);
}

.section-head .eyebrow::before {
  background: var(--fg-muted);
}

.section-head h2 {
  font-size: clamp(28px, 3.6vw, 42px);
  line-height: 1.1;
  font-weight: 600;
  letter-spacing: -0.02em;
  margin-bottom: 16px;
}

.section-head p {
  color: var(--fg-secondary);
  font-size: 16px;
}

/* --------------------------------------------------------------------------
   Features grid
   -------------------------------------------------------------------------- */
.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.feature-card {
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg);
  background: var(--bg-secondary);
  padding: 28px 24px;
  transition: border-color 0.18s, background 0.18s, transform 0.18s;
}

.feature-card:hover {
  border-color: var(--accent);
  background: var(--bg-hover);
  transform: translateY(-3px);
}

.feature-card .icon {
  width: 40px;
  height: 40px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-primary);
  background: var(--bg-tertiary);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
  margin-bottom: 20px;
}

.feature-card h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 6px;
}

.feature-card .badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--accent);
  margin-bottom: 14px;
}

.feature-card p {
  font-size: 14px;
  color: var(--fg-secondary);
}

/* --------------------------------------------------------------------------
   Why grid
   -------------------------------------------------------------------------- */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.why-card {
  display: flex;
  gap: 18px;
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg);
  background: var(--bg-secondary);
  padding: 26px;
  transition: border-color 0.18s, background 0.18s;
}

.why-card:hover {
  border-color: var(--accent);
  background: var(--bg-hover);
}

.why-card .num {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--accent);
  padding-top: 3px;
  flex: none;
}

.why-card h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 8px;
}

.why-card p {
  font-size: 14px;
  color: var(--fg-secondary);
}

/* --------------------------------------------------------------------------
   Compliance
   -------------------------------------------------------------------------- */
.compliance-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.compliance-card {
  text-align: center;
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg);
  background: var(--bg-secondary);
  padding: 32px 20px;
}

.compliance-card .platform {
  font-size: 15px;
  font-weight: 600;
  color: var(--fg-secondary);
  margin-bottom: 16px;
}

.compliance-card .lufs {
  font-family: var(--font-mono);
  font-size: 34px;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: -0.02em;
}

.compliance-card .unit {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--fg-muted);
  margin-top: 6px;
  letter-spacing: 0.1em;
}

.compliance-note {
  margin-top: 32px;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  color: var(--fg-muted);
  text-align: center;
}

/* --------------------------------------------------------------------------
   Workflow
   -------------------------------------------------------------------------- */
.workflow-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  counter-reset: step;
}

.step {
  position: relative;
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg);
  background: var(--bg-secondary);
  padding: 28px 24px;
}

.step .step-num {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--accent);
  letter-spacing: 0.12em;
  margin-bottom: 18px;
}

.step h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 10px;
}

.step p {
  font-size: 14px;
  color: var(--fg-secondary);
}

/* --------------------------------------------------------------------------
   Download
   -------------------------------------------------------------------------- */
.download-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.download-card {
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg);
  background: var(--bg-secondary);
  padding: 30px 24px;
  text-align: center;
  transition: border-color 0.18s, background 0.18s, transform 0.18s;
}

.download-card:hover {
  border-color: var(--accent);
  background: var(--bg-hover);
  transform: translateY(-3px);
}

.download-card .os-icon {
  width: 40px;
  height: 40px;
  margin: 0 auto 18px;
  color: var(--accent);
}

.download-card .os-icon svg {
  width: 100%;
  height: 100%;
  display: block;
}

.download-card h3 {
  font-size: 17px;
  font-weight: 600;
  margin-bottom: 6px;
}

.download-card .desc {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--fg-muted);
  margin-bottom: 20px;
  letter-spacing: 0.04em;
}

.download-actions {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.channel-note {
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-lg);
  background: var(--bg-secondary);
  padding: 20px 24px;
  margin-bottom: 32px;
}

.channel-note h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 8px;
}

.channel-note p {
  font-size: 14px;
  color: var(--fg-secondary);
}

.community {
  margin-top: 56px;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 40px;
  align-items: center;
  border: 1px solid var(--border-primary);
  border-radius: var(--radius-xl);
  background: var(--bg-secondary);
  padding: 40px;
}

.community .qr img {
  width: 180px;
  height: 180px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-primary);
}

.community h3 {
  font-size: 22px;
  font-weight: 600;
  margin-bottom: 12px;
}

.community p {
  color: var(--fg-secondary);
  margin-bottom: 20px;
  max-width: 480px;
}

.download-note {
  margin-top: 32px;
  text-align: center;
  color: var(--fg-muted);
  font-size: 14px;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.site-footer {
  padding: 56px 0 40px;
  background: var(--bg-secondary);
}

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 28px;
}

.footer-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

.footer-brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.footer-brand .logo-mark {
  width: 28px;
  height: 28px;
}

.footer-brand .tagline {
  font-size: 14px;
  color: var(--fg-secondary);
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  padding-top: 24px;
  border-top: 1px solid var(--border-primary);
  font-size: 13px;
  color: var(--fg-muted);
}

.footer-bottom .publisher {
  font-family: var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* --------------------------------------------------------------------------
   Reveal animation
   -------------------------------------------------------------------------- */
.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
  opacity: 1;
  transform: none;
}

/* --------------------------------------------------------------------------
   Responsive
   -------------------------------------------------------------------------- */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .compliance-grid { grid-template-columns: repeat(2, 1fr); }
  .hero-grid { grid-template-columns: 1fr; }
  .hero-visual { display: none; }
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 68px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    background: var(--bg-secondary);
    border-bottom: 1px solid var(--border-primary);
    padding: 12px 16px 16px;
    gap: 4px;
    display: none;
  }

  .nav-links.open {
    display: flex;
  }

  .nav-links a {
    padding: 12px 14px;
  }

  .nav-toggle {
    display: inline-flex;
  }

  .grid-2 { grid-template-columns: 1fr; }
  .workflow-grid { grid-template-columns: 1fr; }
  .download-grid { grid-template-columns: 1fr; }
  .community { grid-template-columns: 1fr; text-align: center; }
  .community .qr { justify-self: center; }
  .section { padding: 64px 0; }
  .hero { padding: 64px 0 56px; }
}