/* ==========================================================================
   HIJIN DESIGN SYSTEM v4.5
   Private Intelligence. On Your Machine.
   Restrained, technical, modern desktop software aesthetic.
   ========================================================================== */

:root {
  /* Color Palette (Section 4) */
  --bg-base: #030509;
  --bg-surface: #060912;
  --bg-elevated: #0A0F1A;
  --bg-card: #0D1420;
  --bg-card-hover: #111A28;

  --primary: #35A8FF;
  --primary-dark: #2563FF;
  --primary-glow: rgba(53, 168, 255, 0.12);
  --secondary: #7567FF;
  --secondary-light: #A78BFA;

  --text-primary: #F5F7FA;
  --text-body: #C9D1DC;
  --text-muted: #8793A3;
  --text-dim: #526075;

  --border-subtle: rgba(255, 255, 255, 0.08);
  --border-active: rgba(53, 168, 255, 0.35);
  --border-bright: rgba(255, 255, 255, 0.16);

  --status-verified: #10B981;
  --status-warning: #F59E0B;
  --status-error: #EF4444;

  /* Typography Stacks */
  --font-display: 'Plus Jakarta Sans', system-ui, -apple-system, sans-serif;
  --font-body: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', Consolas, 'SF Mono', monospace;

  --container-max: 1200px;
  --radius-sm: 6px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 16px;
  --radius-pill: 9999px;
  --transition: 0.18s cubic-bezier(0.16, 1, 0.3, 1);
}

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

html {
  font-family: var(--font-body);
  background-color: var(--bg-base);
  color: var(--text-body);
  font-size: 16px;
  line-height: 1.6;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
  scroll-behavior: smooth;
}

body {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  position: relative;
  overflow-x: hidden;
}

/* Ambient canvas background */
.bg-canvas {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: -1;
  background-image: 
    radial-gradient(ellipse 60% 40% at 50% -10%, rgba(37, 99, 255, 0.14), transparent),
    radial-gradient(ellipse 40% 30% at 85% 60%, rgba(117, 103, 255, 0.06), transparent),
    linear-gradient(rgba(255, 255, 255, 0.015) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.015) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 48px 48px, 48px 48px;
}

/* Typography elements */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  color: var(--text-primary);
  font-weight: 800;
  line-height: 1.2;
}

h1 {
  font-size: clamp(2.4rem, 5vw, 3.8rem);
  letter-spacing: -0.035em;
  margin-bottom: 1.25rem;
}

h2 {
  font-size: clamp(1.75rem, 3.5vw, 2.4rem);
  letter-spacing: -0.025em;
  margin-bottom: 0.75rem;
}

h3 {
  font-size: 1.25rem;
  letter-spacing: -0.015em;
  margin-bottom: 0.5rem;
}

p {
  color: var(--text-body);
  margin-bottom: 1rem;
}

p:last-child {
  margin-bottom: 0;
}

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

/* Layout container */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 4.5rem 1.5rem;
}

.container-narrow {
  max-width: 860px;
}

/* Header & Navigation */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: 64px;
  background: rgba(3, 5, 9, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
  transition: border-color var(--transition), box-shadow var(--transition);
}

.site-header.scrolled {
  border-bottom-color: var(--border-bright);
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.5);
}

.nav-container {
  max-width: var(--container-max);
  height: 100%;
  margin: 0 auto;
  padding: 0 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 800;
  letter-spacing: 0.05em;
  color: var(--text-primary);
}

.brand-icon {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, rgba(53, 168, 255, 0.2), rgba(37, 99, 255, 0.1));
  border: 1px solid rgba(53, 168, 255, 0.35);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
}

.nav-link {
  padding: 0.45rem 0.85rem;
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--text-muted);
  border-radius: var(--radius-md);
  transition: color var(--transition), background-color var(--transition);
}

.nav-link:hover {
  color: var(--text-primary);
  background-color: rgba(255, 255, 255, 0.04);
}

.nav-link.active {
  color: var(--text-primary);
  background-color: rgba(255, 255, 255, 0.06);
  font-weight: 600;
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.nav-hamburger {
  display: none;
  background: none;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  padding: 0.45rem;
  cursor: pointer;
  color: var(--text-primary);
}

.nav-hamburger span {
  display: block;
  width: 18px;
  height: 2px;
  background: currentColor;
  margin: 3px 0;
  transition: transform var(--transition);
}

.nav-mobile-drawer {
  display: none;
  position: fixed;
  top: 64px;
  left: 0;
  right: 0;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border-bright);
  padding: 1.5rem;
  flex-direction: column;
  gap: 0.5rem;
  z-index: 99;
}

.nav-mobile-drawer.open {
  display: flex;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.625rem 1.25rem;
  font-size: 0.9rem;
  font-weight: 600;
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all var(--transition);
  border: 1px solid transparent;
  white-space: nowrap;
}

.btn-primary {
  background: linear-gradient(135deg, #35A8FF 0%, #2563FF 100%);
  color: #ffffff;
  box-shadow: 0 4px 14px rgba(37, 99, 255, 0.28), inset 0 1px 0 rgba(255, 255, 255, 0.25);
}

.btn-primary:hover {
  filter: brightness(1.08);
  transform: translateY(-1px);
  box-shadow: 0 6px 20px rgba(37, 99, 255, 0.4), inset 0 1px 0 rgba(255, 255, 255, 0.3);
}

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

.btn-secondary:hover {
  background: var(--bg-card-hover);
  border-color: var(--border-bright);
  color: #fff;
  transform: translateY(-1px);
}

.btn-ghost {
  background: transparent;
  color: var(--text-muted);
}

.btn-ghost:hover {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
}

.btn-sm {
  padding: 0.35rem 0.75rem;
  font-size: 0.8125rem;
}

.btn-lg {
  padding: 0.8rem 1.6rem;
  font-size: 1rem;
}

.btn-xl {
  padding: 1rem 2rem;
  font-size: 1.05rem;
  border-radius: 10px;
}

/* Badges */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.25rem 0.65rem;
  font-size: 0.75rem;
  font-family: var(--font-mono);
  font-weight: 500;
  border-radius: var(--radius-pill);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border-subtle);
  color: var(--text-muted);
}

.badge-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--primary);
}

.badge-success {
  background: rgba(16, 185, 129, 0.1);
  border-color: rgba(16, 185, 129, 0.25);
  color: var(--status-verified);
}

.badge-success .badge-dot {
  background: var(--status-verified);
}

.badge-warning {
  background: rgba(245, 158, 11, 0.1);
  border-color: rgba(245, 158, 11, 0.25);
  color: var(--status-warning);
}

.badge-primary {
  background: rgba(53, 168, 255, 0.1);
  border-color: rgba(53, 168, 255, 0.25);
  color: var(--primary);
}

/* Hero Section */
.hero {
  padding: 5rem 1.5rem 3.5rem;
  text-align: center;
  max-width: 920px;
  margin: 0 auto;
}

.hero-subtitle {
  font-size: clamp(1.05rem, 2vw, 1.25rem);
  color: var(--text-body);
  line-height: 1.65;
  margin-bottom: 2rem;
  max-width: 780px;
  margin-left: auto;
  margin-right: auto;
}

.hero-ctas {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 2.5rem;
}

/* Grid systems */
.grid-2 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(360px, 1fr));
  gap: 1.5rem;
}

.grid-3 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 1.5rem;
}

.grid-4 {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 1.25rem;
}

/* Cards */
.card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  transition: transform var(--transition), border-color var(--transition), box-shadow var(--transition);
  position: relative;
}

.card:hover {
  border-color: rgba(53, 168, 255, 0.25);
  transform: translateY(-2px);
  box-shadow: 0 12px 32px rgba(0, 0, 0, 0.35);
}

.card-icon {
  width: 42px;
  height: 42px;
  border-radius: var(--radius-md);
  background: rgba(53, 168, 255, 0.1);
  border: 1px solid rgba(53, 168, 255, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--primary);
  margin-bottom: 1.25rem;
}

/* Workflows (UNDERSTAND -> REASON -> VERIFY -> CREATE) */
.flow-step {
  display: flex;
  gap: 1.25rem;
  padding: 1.5rem;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
}

.flow-step-num {
  font-family: var(--font-mono);
  font-size: 1.25rem;
  font-weight: 700;
  color: var(--primary);
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: rgba(53, 168, 255, 0.1);
  border: 1px solid rgba(53, 168, 255, 0.2);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

/* Section Header */
.section-header {
  text-align: center;
  max-width: 680px;
  margin: 0 auto 3rem;
}

.section-label {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--primary);
  margin-bottom: 0.5rem;
}

/* Tables */
.table-wrapper {
  width: 100%;
  overflow-x: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle);
  background: var(--bg-card);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  text-align: left;
  font-size: 0.88rem;
}

.data-table th,
.data-table td {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--border-subtle);
}

.data-table th {
  background: var(--bg-surface);
  color: var(--text-primary);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

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

.data-table tr:hover td {
  background: rgba(255, 255, 255, 0.02);
}

.cell-pass {
  color: var(--status-verified);
  font-weight: 600;
}

.cell-fail {
  color: var(--text-dim);
}

/* Code box */
.code-box {
  background: #020306;
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  margin: 1rem 0;
}

.code-box-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.5rem 1rem;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border-subtle);
  color: var(--text-muted);
  font-size: 0.75rem;
}

.code-box pre {
  padding: 1rem;
  overflow-x: auto;
  color: #fff;
}

/* Callout */
.callout {
  padding: 1.25rem 1.5rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-subtle);
  background: var(--bg-card);
  margin: 1.5rem 0;
}

.callout-primary {
  border-color: rgba(53, 168, 255, 0.3);
  background: rgba(53, 168, 255, 0.05);
}

.callout-primary h4 {
  color: var(--primary);
  margin-bottom: 0.4rem;
}

/* Model Catalog Cards (Section 18) */
.model-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 1.75rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  transition: transform var(--transition), border-color var(--transition);
}

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

.model-meta-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.75rem;
  padding: 1rem;
  background: var(--bg-surface);
  border-radius: var(--radius-md);
  font-size: 0.8125rem;
  border: 1px solid var(--border-subtle);
}

.model-meta-item span {
  display: block;
  color: var(--text-dim);
  font-size: 0.75rem;
  margin-bottom: 2px;
}

.model-meta-item strong {
  color: var(--text-primary);
  font-family: var(--font-mono);
}

/* Documentation Layout (Section 32) */
.docs-layout {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 3rem;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 3rem 1.5rem;
}

.docs-sidebar {
  position: sticky;
  top: 96px;
  height: calc(100vh - 120px);
  overflow-y: auto;
  padding-right: 1rem;
}

.docs-toc {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.docs-toc a {
  display: block;
  padding: 0.45rem 0.75rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  border-radius: var(--radius-md);
  transition: all var(--transition);
}

.docs-toc a:hover,
.docs-toc a.active {
  color: var(--text-primary);
  background: rgba(255, 255, 255, 0.05);
}

.docs-toc a.active {
  font-weight: 600;
  border-left: 2px solid var(--primary);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

.docs-content {
  min-width: 0;
}

.docs-section {
  padding-bottom: 3.5rem;
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: 3rem;
}

.docs-section:last-child {
  border-bottom: none;
}

/* Footer (Section 55) */
.site-footer {
  margin-top: auto;
  background: var(--bg-surface);
  border-top: 1px solid var(--border-subtle);
  padding: 4rem 1.5rem 2.5rem;
}

.footer-inner {
  max-width: var(--container-max);
  margin: 0 auto;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-brand p {
  color: var(--text-muted);
  font-size: 0.9rem;
  margin: 0.75rem 0 1.25rem;
  max-width: 320px;
}

.footer-tech-note {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--primary);
  background: rgba(53, 168, 255, 0.08);
  border: 1px solid rgba(53, 168, 255, 0.2);
  padding: 0.35rem 0.75rem;
  border-radius: var(--radius-pill);
}

.footer-col h4 {
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-primary);
  margin-bottom: 1rem;
}

.footer-links {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.footer-links a {
  color: var(--text-muted);
  font-size: 0.85rem;
  transition: color var(--transition);
}

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

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 2rem;
  border-top: 1px solid var(--border-subtle);
  font-size: 0.8125rem;
  color: var(--text-dim);
  flex-wrap: wrap;
  gap: 1rem;
}

.footer-bottom-right {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.footer-status-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--status-verified);
}

/* Responsive */
@media (max-width: 900px) {
  .docs-layout {
    grid-template-columns: 1fr;
  }
  .docs-sidebar {
    display: none;
  }
  .footer-grid {
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
  }
}

@media (max-width: 768px) {
  .nav-links, .nav-actions {
    display: none;
  }
  .nav-hamburger {
    display: block;
  }
  .footer-grid {
    grid-template-columns: 1fr;
  }
}