:root {
  --bg-obsidian: #090d14;
  --bg-surface: #111723;
  --bg-elevated: #172031;
  --bg-hover: #1d283d;
  --border-subtle: #233047;
  --border-strong: #324565;

  --text-primary: #edf2f7;
  --text-secondary: #9ba9be;
  --text-muted: #64748b;

  --accent-emerald: #10b981;
  --accent-emerald-dim: rgba(16, 185, 129, 0.14);
  --accent-cyan: #06b6d4;
  --accent-cyan-dim: rgba(6, 182, 212, 0.14);
  --accent-amber: #f59e0b;
  --accent-amber-dim: rgba(245, 158, 11, 0.15);
  --accent-crimson: #ef4444;
  --accent-violet: #8b5cf6;

  --font-sans: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  --font-mono: ui-monospace, "JetBrains Mono", "Fira Code", "SFMono-Regular", Menlo, Consolas, monospace;

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --shadow-card: 0 4px 20px rgba(0, 0, 0, 0.45);
}

[data-theme="light"] {
  --bg-obsidian: #f4f6fa;
  --bg-surface: #ffffff;
  --bg-elevated: #edf2f7;
  --bg-hover: #e2e8f0;
  --border-subtle: #cbd5e1;
  --border-strong: #94a3b8;

  --text-primary: #0f172a;
  --text-secondary: #334155;
  --text-muted: #64748b;

  --accent-emerald: #059669;
  --accent-emerald-dim: rgba(5, 150, 105, 0.12);
  --accent-cyan: #0284c7;
  --accent-cyan-dim: rgba(2, 132, 199, 0.12);
  --accent-amber: #d97706;
  --accent-amber-dim: rgba(217, 119, 6, 0.14);
  --accent-crimson: #dc2626;
  --accent-violet: #7c3aed;

  --shadow-card: 0 4px 18px rgba(15, 23, 42, 0.08);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  padding: 0;
  background-color: var(--bg-obsidian);
  color: var(--text-primary);
  font-family: var(--font-sans);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

body {
  background-image:
    radial-gradient(circle at 15% 10%, rgba(16, 185, 129, 0.07), transparent 35%),
    radial-gradient(circle at 85% 20%, rgba(6, 182, 212, 0.07), transparent 35%),
    linear-gradient(to right, rgba(35, 48, 71, 0.22) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(35, 48, 71, 0.22) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 48px 48px, 48px 48px;
  min-height: 100vh;
}

a {
  color: var(--accent-cyan);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

code,
pre,
.mono {
  font-family: var(--font-mono);
}

/* Top Navbar */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(14px);
  background: rgba(9, 13, 20, 0.85);
  border-bottom: 1px solid var(--border-subtle);
}

.nav-container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0.85rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: -0.02em;
  color: var(--text-primary);
  text-decoration: none !important;
}

.brand img {
  width: 34px;
  height: 34px;
  border-radius: 8px;
}

.brand-version {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.15rem 0.5rem;
  border-radius: 999px;
  background: var(--accent-emerald-dim);
  color: var(--accent-emerald);
  border: 1px solid rgba(16, 185, 129, 0.35);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 1.25rem;
  flex-wrap: wrap;
}

.nav-links a {
  color: var(--text-secondary);
  font-size: 0.92rem;
  font-weight: 500;
  text-decoration: none;
  transition: color 0.15s ease;
}

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.6rem 1.15rem;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.15s ease;
  text-decoration: none !important;
}

.btn-primary {
  background: linear-gradient(135deg, var(--accent-emerald), #059669);
  color: #04130d;
  box-shadow: 0 2px 14px rgba(16, 185, 129, 0.3);
}

.btn-primary:hover {
  filter: brightness(1.08);
  transform: translateY(-1px);
}

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

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

.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.3rem 0.7rem;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
}

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--text-muted);
}

.status-dot.online {
  background: var(--accent-emerald);
  box-shadow: 0 0 8px var(--accent-emerald);
}

.status-dot.fallback {
  background: var(--accent-amber);
  box-shadow: 0 0 8px var(--accent-amber);
}

/* Hero Section */
.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 1.5rem;
}

.hero {
  padding: 4.25rem 0 3rem;
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 2.5rem;
  align-items: center;
}

@media (max-width: 960px) {
  .hero {
    grid-template-columns: 1fr;
    padding: 2.5rem 0;
  }
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent-cyan);
  background: var(--accent-cyan-dim);
  border: 1px solid rgba(6, 182, 212, 0.3);
  padding: 0.3rem 0.75rem;
  border-radius: 999px;
  margin-bottom: 1rem;
}

.hero h1 {
  font-size: clamp(2.1rem, 4vw, 3.25rem);
  line-height: 1.12;
  letter-spacing: -0.03em;
  margin: 0 0 1.1rem;
}

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

.hero-lead {
  font-size: 1.08rem;
  color: var(--text-secondary);
  margin: 0 0 1.75rem;
  max-width: 60ch;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.85rem;
  margin-bottom: 2rem;
}

.telemetry-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.85rem;
}

@media (max-width: 600px) {
  .telemetry-strip {
    grid-template-columns: 1fr;
  }
}

.telemetry-box {
  background: rgba(17, 23, 35, 0.85);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.75rem 0.9rem;
}

.telemetry-box .label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--text-muted);
  text-transform: uppercase;
}

.telemetry-box .value {
  font-family: var(--font-mono);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-top: 0.2rem;
}

/* Invite Launcher Card on Landing Page */
.launcher-panel {
  background: var(--bg-surface);
  border: 1px solid var(--border-strong);
  border-radius: var(--radius-lg);
  padding: 1.5rem;
  box-shadow: var(--shadow-card);
}

.launcher-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1rem;
  padding-bottom: 0.75rem;
  border-bottom: 1px solid var(--border-subtle);
}

.launcher-title {
  font-weight: 700;
  font-size: 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.invite-input {
  width: 100%;
  background: var(--bg-obsidian);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  padding: 0.75rem;
  resize: vertical;
  min-height: 76px;
}

.invite-input:focus {
  outline: none;
  border-color: var(--accent-emerald);
}

.decoded-preview {
  margin-top: 0.85rem;
  background: var(--bg-obsidian);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.75rem;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--text-secondary);
}

.decoded-row {
  display: flex;
  justify-content: space-between;
  gap: 0.5rem;
  padding: 0.2rem 0;
  border-bottom: 1px dashed rgba(100, 116, 139, 0.2);
}

.decoded-row:last-child {
  border-bottom: none;
}

/* Keep-Style Preview Grid on Landing Page */
.section {
  padding: 3rem 0;
  border-top: 1px solid var(--border-subtle);
}

.section-header {
  margin-bottom: 2rem;
}

.section-header h2 {
  font-size: 1.75rem;
  margin: 0 0 0.4rem;
  letter-spacing: -0.02em;
}

.section-header p {
  color: var(--text-secondary);
  margin: 0;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1.15rem;
}

.keep-preview-card {
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  transition: transform 0.15s ease, border-color 0.15s ease;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.keep-preview-card:hover {
  transform: translateY(-2px);
  border-color: var(--accent-cyan);
}

.keep-preview-card.emerald {
  background: linear-gradient(180deg, rgba(16, 185, 129, 0.1), var(--bg-surface));
  border-color: rgba(16, 185, 129, 0.35);
}

.keep-preview-card.cyan {
  background: linear-gradient(180deg, rgba(6, 182, 212, 0.1), var(--bg-surface));
  border-color: rgba(6, 182, 212, 0.35);
}

.keep-preview-card.amber {
  background: linear-gradient(180deg, rgba(245, 158, 11, 0.1), var(--bg-surface));
  border-color: rgba(245, 158, 11, 0.35);
}

.keep-preview-card h3 {
  margin: 0 0 0.5rem;
  font-size: 1.05rem;
}

.keep-preview-card p {
  margin: 0 0 1rem;
  color: var(--text-secondary);
  font-size: 0.9rem;
}

.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.chip {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  padding: 0.18rem 0.55rem;
  border-radius: 6px;
  background: rgba(9, 13, 20, 0.75);
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
}

/* Architecture Table */
.spec-table-wrap {
  overflow-x: auto;
  background: var(--bg-surface);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
}

.spec-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}

.spec-table th,
.spec-table td {
  padding: 0.9rem 1.1rem;
  text-align: left;
  border-bottom: 1px solid var(--border-subtle);
}

.spec-table th {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  text-transform: uppercase;
  color: var(--text-muted);
  background: rgba(9, 13, 20, 0.5);
}

.spec-table tr:last-child td {
  border-bottom: none;
}

.site-footer {
  border-top: 1px solid var(--border-subtle);
  padding: 2rem 0;
  margin-top: 2rem;
  color: var(--text-muted);
  font-size: 0.85rem;
}

[data-theme="light"] .site-header {
  background: rgba(244, 246, 250, 0.9);
}

[data-theme="light"] .telemetry-box,
[data-theme="light"] .chip,
[data-theme="light"] .spec-table th {
  background: var(--bg-elevated);
}

/* QR Invite & Drag-and-Drop Zone */
.qr-invite-row {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.85rem;
  align-items: stretch;
  margin-top: 0.8rem;
}

@media (max-width: 520px) {
  .qr-invite-row {
    grid-template-columns: 1fr;
  }
}

.qr-canvas-box {
  background: #ffffff;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-sm);
  padding: 0.4rem;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.qr-canvas-box canvas {
  width: 116px;
  height: 116px;
  image-rendering: pixelated;
  display: block;
}

.drop-zone {
  border: 1.5px dashed var(--border-strong);
  border-radius: var(--radius-sm);
  background: var(--bg-obsidian);
  padding: 0.7rem 0.85rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.35rem;
  font-size: 0.78rem;
  color: var(--text-secondary);
  cursor: pointer;
  transition: border-color 0.15s ease, background 0.15s ease;
}

.drop-zone:hover,
.drop-zone.highlight {
  border-color: var(--accent-emerald);
  background: var(--accent-emerald-dim);
  color: var(--text-primary);
}