/* ============================================
   Palace Research Report — Stylesheet
   ============================================ */

:root {
  --color-bg: #0d1117;
  --color-surface: #161b22;
  --color-surface-raised: #1a1f26;
  --color-text: #e6edf3;
  --color-text-secondary: #d8dee6;
  --color-text-tertiary: #a2aab4;
  --color-text-faint: #6b7380;
  --color-border: #21262d;
  --color-border-light: #1a1f26;
  --color-accent: #58a6ff;
  --color-accent-light: rgba(88,166,255,0.08);
  --color-accent-border: rgba(88,166,255,0.2);
  --color-core: #bc8cff;
  --color-core-light: rgba(188,140,255,0.08);
  --color-core-border: rgba(188,140,255,0.2);
  --color-mechanism: #58a6ff;
  --color-mechanism-light: rgba(88,166,255,0.08);
  --color-mechanism-border: rgba(88,166,255,0.2);
  --color-supporting: #3fb950;
  --color-supporting-light: rgba(63,185,80,0.08);
  --color-supporting-border: rgba(63,185,80,0.2);
  --color-amber: #d29922;
  --color-amber-light: rgba(210,153,34,0.08);
  --color-amber-border: rgba(210,153,34,0.2);
  --color-red: #f85149;
  --color-sidebar: #0d1117;
  --color-sidebar-text: #8b949e;
  --color-sidebar-hover: #161b22;
  --color-sidebar-active: #58a6ff;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-serif: 'Lora', Georgia, serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'SF Mono', monospace;

  --sidebar-width: 260px;
  --content-max: 780px;
  --radius: 6px;
  --radius-sm: 3px;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.3);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.4);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.5);
  --transition-base: 0.2s cubic-bezier(0.25, 0.1, 0.25, 1);
  --transition-spring: 0.35s cubic-bezier(0.34, 1.56, 0.64, 1);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 32px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  color: var(--color-text);
  background: var(--color-bg);
  line-height: 1.75;
  font-size: 16px;
  letter-spacing: 0.01em;
  /* Dot grid from diagrams */
  background-image: url("data:image/svg+xml,%3Csvg width='20' height='20' xmlns='http://www.w3.org/2000/svg'%3E%3Ccircle cx='10' cy='10' r='0.5' fill='%2321262d' fill-opacity='0.5'/%3E%3C/svg%3E");
  background-size: 20px 20px;
}

/* ---- Sidebar ---- */
.sidebar {
  position: fixed;
  top: 0;
  left: 0;
  width: var(--sidebar-width);
  height: 100vh;
  background: var(--color-sidebar);
  border-right: 1px solid var(--color-border);
  display: flex;
  flex-direction: column;
  z-index: 100;
  overflow-y: auto;
  scrollbar-width: none;
  -ms-overflow-style: none;
}
.sidebar::-webkit-scrollbar { display: none; }

.sidebar-header {
  display: block;
  padding: 28px 24px 20px;
  border-bottom: 1px solid var(--color-border);
  text-decoration: none;
  transition: background var(--transition-base);
  cursor: pointer;
}
.sidebar-header:hover {
  background: var(--color-sidebar-hover);
}

.logo {
  display: block;
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.subtitle {
  display: block;
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--color-text-faint);
  margin-top: 6px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

.nav-links {
  list-style: none;
  padding: 12px 0;
  flex: 1;
}

.nav-link {
  display: block;
  padding: 8px 24px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 400;
  color: var(--color-sidebar-text);
  text-decoration: none;
  transition: color var(--transition-base), background var(--transition-base), border-color var(--transition-base), padding var(--transition-base);
  border-left: 2px solid transparent;
  letter-spacing: 0.01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.nav-link:hover {
  color: var(--color-text);
  background: var(--color-sidebar-hover);
  padding-left: 28px;
}

.nav-link.active {
  color: var(--color-text);
  border-left-color: var(--color-amber);
  background: var(--color-amber-light);
}

.sidebar-footer {
  padding: 16px 20px;
  border-top: 1px solid var(--color-border);
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--color-text-faint);
  line-height: 1.6;
}

.sidebar-author {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 14px;
}
.author-avatar {
  width: 30px;
  height: 30px;
  border-radius: 50%;
  border: 1.5px solid var(--color-border);
  object-fit: cover;
  flex-shrink: 0;
}
.author-name {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  color: var(--color-text);
  letter-spacing: 0.02em;
  line-height: 1;
  flex: 1;
  min-width: 0;
}
.author-social {
  display: flex;
  gap: 4px;
  flex-shrink: 0;
}
.social-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 5px;
  background: transparent;
  color: var(--color-text-faint);
  transition: color 0.2s, background 0.2s;
}
.social-btn:hover {
  color: var(--color-text);
  background: rgba(255, 255, 255, 0.06);
}
.sidebar-uw {
  padding-top: 12px;
  border-top: 1px solid var(--color-border);
}
.uw-hcde-logo {
  width: 100%;
  height: auto;
  opacity: 0.5;
  transition: opacity 0.25s;
}
.uw-hcde-logo:hover {
  opacity: 0.75;
}

/* ---- Mobile menu ---- */
.menu-toggle {
  display: none;
  position: fixed;
  top: 16px;
  left: 16px;
  z-index: 200;
  width: 40px;
  height: 40px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  cursor: pointer;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 5px;
}

.menu-toggle span {
  display: block;
  width: 20px;
  height: 1.5px;
  background: var(--color-text-tertiary);
  border-radius: 1px;
  transition: all 0.2s ease;
}

.overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  z-index: 90;
}

/* ---- Main Content ---- */
.content {
  margin-left: var(--sidebar-width);
  min-height: 100vh;
}

.hero {
  padding: 80px 48px 56px;
  max-width: calc(var(--content-max) + 96px);
  margin: 0 auto;
  border-bottom: 1px solid var(--color-border);
}

.hero-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--color-amber);
  margin-bottom: 20px;
}

.hero h1 {
  font-family: var(--font-serif);
  font-size: 36px;
  font-weight: 600;
  line-height: 1.2;
  color: var(--color-text);
  letter-spacing: -0.02em;
  max-width: 640px;
}

.hero-sub {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--color-text-tertiary);
  margin-top: 16px;
  letter-spacing: 0.01em;
}

.hero-author {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-top: 20px;
  letter-spacing: 0.02em;
}

/* ---- Sections ---- */
.section {
  padding: 56px 48px;
  max-width: calc(var(--content-max) + 96px);
  margin: 0 auto;
  border-bottom: 1px solid var(--color-border);
}

.section h2 {
  font-family: var(--font-serif);
  font-size: 28px;
  font-weight: 600;
  margin-bottom: 24px;
  letter-spacing: -0.02em;
  padding-bottom: 16px;
  border-bottom: 1px solid var(--color-border);
}

.section h3 {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  margin-top: 40px;
  margin-bottom: 16px;
  color: var(--color-text-tertiary);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.section h4 {
  font-size: 15px;
  font-weight: 600;
  margin-bottom: 6px;
  color: var(--color-text);
}

.section p {
  margin-bottom: 12px;
  color: var(--color-text-secondary);
}

.section p strong {
  color: var(--color-text);
  font-weight: 600;
}

.section ol, .section ul {
  margin-bottom: 16px;
  padding-left: 24px;
  color: var(--color-text-secondary);
}

.section li {
  margin-bottom: 6px;
}

/* ---- Summary card ---- */
.summary-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-amber);
  border-radius: var(--radius);
  padding: 28px;
  margin-bottom: 24px;
  transition: border-color var(--transition-base);
}
.summary-card:hover {
  border-color: rgba(210,153,34,0.4);
}

.summary-card p:last-child {
  margin-bottom: 0;
}

/* ---- Key insight ---- */
.key-insight {
  background: var(--color-amber-light);
  border: 1px solid var(--color-amber-border);
  border-left: 3px solid var(--color-amber);
  border-radius: var(--radius);
  padding: 24px 28px;
  margin: 24px 0;
}

.key-insight-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--color-amber) !important;
  margin-bottom: 8px !important;
}

.key-insight p:last-child {
  margin-bottom: 0;
  color: var(--color-text);
  font-size: 16px;
  font-weight: 450;
  line-height: 1.6;
}

/* ---- Definitions ---- */
.definitions {
  margin-top: 8px;
}

.definitions dt {
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--color-text);
  margin-top: 16px;
  font-size: 13px;
  letter-spacing: 0.02em;
}

.definitions dd {
  color: var(--color-text-secondary);
  margin-left: 0;
  padding-left: 16px;
  border-left: 2px solid var(--color-border);
  margin-top: 4px;
  font-size: 15px;
}

/* ---- Theory grid ---- */
.theory-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 16px;
  margin-bottom: 16px;
}

.theory-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  transition: border-color var(--transition-base);
}
.theory-card:hover {
  border-color: var(--color-text-faint);
}

.theory-card h4 {
  font-size: 14px;
  margin-bottom: 4px;
}

.theory-author {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-text-faint) !important;
  margin-bottom: 10px !important;
  letter-spacing: 0.02em;
}

.theory-card p:last-child {
  margin-bottom: 0;
  font-size: 14px;
  line-height: 1.6;
}

/* ---- Research questions ---- */
.rq-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.rq-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px 24px;
  transition: border-color var(--transition-base);
}
.rq-card:hover {
  border-color: var(--color-text-faint);
}

.rq-label {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  color: var(--color-amber);
  background: var(--color-amber-light);
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  margin-bottom: 8px;
  letter-spacing: 0.06em;
}

.rq-card p {
  margin-bottom: 0;
  font-weight: 450;
  color: var(--color-text);
  font-size: 15px;
}

/* ---- Methods ---- */
.methods-overview {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  margin-bottom: 32px;
}

.method-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 28px 32px;
  transition: border-color var(--transition-base);
}
.method-card:hover {
  border-color: var(--color-text-faint);
}

.method-card-header {
  display: flex;
  align-items: center;
  gap: 16px;
  margin-bottom: 12px;
}

.method-icon {
  color: var(--color-accent);
  flex-shrink: 0;
}

.method-card-header h4 {
  margin: 0;
}

.method-detail {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  color: var(--color-text-faint) !important;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 8px !important;
}

.method-description {
  font-size: 14px;
  line-height: 1.6;
  margin-bottom: 12px;
}

.method-coordinates {
  font-size: 13px;
  color: var(--color-text-secondary);
  border-top: 1px solid var(--color-border);
  padding-top: 12px;
  margin-top: 12px;
  margin-bottom: 12px;
}

.method-card p:last-of-type {
  font-size: 14px;
  margin-bottom: 12px;
}

.status-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  padding: 3px 10px;
  border-radius: 12px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.status-badge.complete {
  background: var(--color-supporting-light);
  color: var(--color-supporting);
}

/* ---- Tables ---- */
.table-wrapper {
  overflow-x: auto;
  margin: 16px 0;
}

table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
}

thead {
  background: var(--color-surface);
}

th {
  text-align: left;
  padding: 10px 16px;
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--color-text-tertiary);
  border-bottom: 1px solid var(--color-border);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text-secondary);
  font-size: 14px;
}

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

.highlight-cell {
  background: var(--color-amber-light);
  font-weight: 600;
  color: var(--color-amber) !important;
}

.caption {
  font-size: 14px;
  color: var(--color-text-tertiary);
  margin-top: 8px;
}

/* ---- Findings ---- */
.finding-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 28px;
  margin-bottom: 20px;
  transition: border-color var(--transition-base);
}
.finding-card:hover {
  border-color: var(--color-text-faint);
}

.finding-card.core {
  border-left: 3px solid var(--color-amber);
}

.finding-card.mechanism {
  border-left: 3px solid var(--color-accent);
}

.finding-card.supporting {
  border-left: 3px solid var(--color-supporting);
}

.finding-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.finding-tag {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 32px;
  height: 24px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  border-radius: var(--radius-sm);
  letter-spacing: 0.04em;
}

.core .finding-tag {
  background: var(--color-amber-light);
  color: var(--color-amber);
}

.mechanism .finding-tag {
  background: var(--color-accent-light);
  color: var(--color-accent);
}

.supporting .finding-tag {
  background: var(--color-supporting-light);
  color: var(--color-supporting);
}

.finding-header h4 {
  margin-bottom: 0;
  font-size: 17px;
}

.finding-card p {
  font-size: 15px;
}

blockquote {
  border-left: 2px solid var(--color-text-faint);
  margin: 16px 0;
  padding: 8px 0 8px 20px;
}

blockquote p {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: 4px;
}

blockquote cite {
  font-family: var(--font-mono);
  font-style: normal;
  font-size: 11px;
  color: var(--color-text-tertiary);
  font-weight: 500;
  letter-spacing: 0.02em;
}

.findings-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.boundary-cases {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  font-size: 14px;
}

.boundary-cases p {
  margin-bottom: 8px;
}

.boundary-cases p:last-child {
  margin-bottom: 0;
}

/* ---- Categories ---- */
.category-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 16px;
}

.category-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  transition: border-color var(--transition-base);
}
.category-card:hover {
  border-color: var(--color-text-faint);
}

.category-tools {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--color-text-faint) !important;
  margin-bottom: 8px !important;
  letter-spacing: 0.02em;
}

.category-card p:last-child {
  font-size: 13px;
  margin-bottom: 0;
}

/* ---- Properties ---- */
.properties-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin: 16px 0;
}

.property-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  position: relative;
  transition: border-color var(--transition-base);
}
.property-card:hover {
  border-color: var(--color-text-faint);
}

.property-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  background: var(--color-amber-light);
  color: var(--color-amber);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  border-radius: 50%;
  border: 1px solid var(--color-amber-border);
  margin-bottom: 12px;
}

.property-card p {
  font-size: 13px;
  margin-bottom: 0;
}

/* ---- Design principles ---- */
.principles-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
}

.principle-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-left: 3px solid var(--color-core);
  border-radius: var(--radius);
  padding: 24px;
  transition: border-color var(--transition-base);
}
.principle-card:hover {
  border-color: var(--color-core-border);
}

.principle-number {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  background: var(--color-core-light);
  color: var(--color-core);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  border-radius: 50%;
  border: 1px solid var(--color-core-border);
  margin-bottom: 12px;
}

.principle-card p {
  font-size: 13px;
  margin-bottom: 8px;
}

.principle-evidence {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--color-text-faint);
  font-weight: 500;
  letter-spacing: 0.04em;
}

/* ---- Requirements ---- */
.req-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin: 16px 0;
}

.req-card {
  background: var(--color-supporting-light);
  border: 1px solid var(--color-supporting-border);
  border-left: 3px solid var(--color-supporting);
  border-radius: var(--radius);
  padding: 24px;
  transition: border-color var(--transition-base);
}
.req-card:hover {
  border-color: var(--color-supporting);
}

/* Outcome card spans full width */
.req-card.outcome-card {
  grid-column: 1 / -1;
}

.req-card h4 {
  color: var(--color-supporting);
  font-size: 13px;
  font-family: var(--font-mono);
  letter-spacing: 0.02em;
}

.req-card p {
  font-size: 13px;
  margin-bottom: 0;
}

/* ---- Badges ---- */
.badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 500;
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.badge.primary {
  background: var(--color-accent-light);
  color: var(--color-accent);
}

.badge.secondary {
  background: rgba(139,148,158,0.1);
  color: var(--color-text-faint);
}

/* ---- Explore grid ---- */
.explore-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin: 16px 0;
}

.explore-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px 24px;
  transition: border-color var(--transition-base);
}
.explore-card:hover {
  border-color: var(--color-text-faint);
}

.explore-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  background: var(--color-accent-light);
  color: var(--color-accent);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  border-radius: 50%;
  border: 1px solid var(--color-accent-border);
  margin-bottom: 10px;
}

.explore-card p {
  font-size: 13px;
  margin-bottom: 0;
}

/* ---- Comparison ---- */
.comparison {
  display: flex;
  align-items: center;
  gap: 20px;
  margin: 16px 0;
}

.comparison-item {
  flex: 1;
  padding: 20px 24px;
  border-radius: var(--radius);
}

.comparison-item.baseline {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
}

.comparison-item.intervention {
  background: var(--color-supporting-light);
  border: 1px solid var(--color-supporting-border);
}

.comparison-item h4 {
  font-family: var(--font-mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-text-faint);
  margin-bottom: 6px;
}

.comparison-item p {
  font-size: 14px;
  margin-bottom: 0;
  color: var(--color-text);
}

.comparison-arrow {
  font-size: 24px;
  color: var(--color-text-tertiary);
  flex-shrink: 0;
}

/* ---- Timeline ---- */
.timeline {
  position: relative;
  margin: 24px 0;
  padding-left: 24px;
  border-left: 2px solid var(--color-border);
}

.timeline-item {
  position: relative;
  padding: 0 0 28px 24px;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-item::before {
  content: '';
  position: absolute;
  left: -29px;
  top: 4px;
  width: 10px;
  height: 10px;
  background: var(--color-amber);
  border: 2px solid var(--color-bg);
  border-radius: 50%;
}

.timeline-week {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--color-amber);
  margin-bottom: 4px;
}

.timeline-item h4 {
  font-size: 15px;
  margin-bottom: 4px;
}

.timeline-item p {
  font-size: 13px;
  margin-bottom: 0;
}

/* ---- Questions ---- */
.questions-list {
  margin-top: 16px;
}

.question-item {
  display: flex;
  gap: 16px;
  margin-bottom: 20px;
}

.q-num {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  border-radius: 50%;
  color: var(--color-text-tertiary);
  margin-top: 2px;
}

.question-item h4 {
  font-size: 14px;
  margin-bottom: 4px;
}

.question-item p {
  font-size: 13px;
  margin-bottom: 0;
}

/* ---- Appendix ---- */
.appendix-list {
  display: grid;
  gap: 16px;
}

.appendix-item {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  transition: border-color var(--transition-base);
}
.appendix-item:hover {
  border-color: var(--color-text-faint);
}
a.appendix-link {
  display: block;
  text-decoration: none;
  color: inherit;
  position: relative;
}
a.appendix-link:hover {
  border-color: var(--color-accent);
}
.appendix-arrow {
  position: absolute;
  top: 24px;
  right: 24px;
  font-family: var(--font-mono);
  font-size: 24px;
  color: var(--color-text-faint);
  transition: color var(--transition-base), transform var(--transition-base);
}
a.appendix-link:hover .appendix-arrow {
  color: var(--color-accent);
  transform: translateX(3px);
}

.appendix-item h4 {
  font-size: 14px;
  margin-bottom: 8px;
}

.appendix-item p {
  font-size: 13px;
  margin-bottom: 0;
}

/* ---- References ---- */
.references-list p {
  font-size: 13px;
  padding-left: 32px;
  text-indent: -32px;
  margin-bottom: 10px;
  color: var(--color-text-secondary);
}

.references-list em {
  font-family: var(--font-serif);
}
.references-list a {
  color: var(--color-accent);
  text-decoration: none;
  font-family: var(--font-mono);
  font-size: 11px;
  word-break: break-all;
  transition: color var(--transition-base);
}
.references-list a:hover {
  color: var(--color-core);
  text-decoration: underline;
}

.cite {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-text-faint);
  letter-spacing: 0.01em;
}

/* ---- Diagrams ---- */
.diagram {
  margin: 32px 0;
  text-align: center;
}

.diagram img {
  max-width: 100%;
  height: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
}

.diagram figcaption {
  font-size: 12px;
  color: var(--color-text-tertiary);
  margin-top: 8px;
}

/* ---- Limitations ---- */
.limitations {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
  font-size: 14px;
}

.limitations p {
  margin-bottom: 8px;
}

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

/* ---- Appendix Page (shared styles for inline + standalone) ---- */
.appendix-page {
  max-width: calc(var(--content-max) + 96px);
  margin: 0 auto;
  padding: 40px 48px 80px;
  min-height: 100vh;
}
.appendix-page h1 {
  font-family: var(--font-serif);
  font-size: 28px;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: var(--color-text);
  margin-bottom: 8px;
  line-height: 1.25;
}
.appendix-page .subtitle-meta {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-text-faint);
  letter-spacing: 0.02em;
  margin-bottom: 32px;
  padding-bottom: 24px;
  border-bottom: 1px solid var(--color-border);
}
.appendix-page h2 {
  font-family: var(--font-serif);
  font-size: 22px;
  font-weight: 600;
  letter-spacing: -0.01em;
  color: var(--color-text);
  margin-top: 48px;
  margin-bottom: 16px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--color-border);
}
.appendix-page h3 {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--color-text-tertiary);
  margin-top: 32px;
  margin-bottom: 12px;
}
.appendix-page h4 {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-text);
  margin-top: 24px;
  margin-bottom: 8px;
}
.appendix-page p {
  color: var(--color-text-secondary);
  line-height: 1.7;
  margin-bottom: 12px;
  font-size: 15px;
}
.appendix-page strong {
  color: var(--color-text);
  font-weight: 600;
}
.appendix-page em {
  font-family: var(--font-serif);
}
.appendix-page ul, .appendix-page ol {
  color: var(--color-text-secondary);
  padding-left: 24px;
  margin-bottom: 16px;
}
.appendix-page li {
  margin-bottom: 6px;
  font-size: 14px;
  line-height: 1.6;
}
.appendix-page blockquote {
  border-left: 2px solid var(--color-text-faint);
  margin: 16px 0;
  padding: 8px 0 8px 20px;
}
.appendix-page blockquote p {
  font-family: var(--font-serif);
  font-style: italic;
  font-size: 15px;
  color: var(--color-text-secondary);
}
.appendix-page table {
  width: 100%;
  border-collapse: collapse;
  font-size: 14px;
  margin: 16px 0;
}
.appendix-page thead {
  background: var(--color-surface);
}
.appendix-page th {
  text-align: left;
  padding: 10px 16px;
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--color-text-tertiary);
  border-bottom: 1px solid var(--color-border);
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
}
.appendix-page td {
  padding: 10px 16px;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text-secondary);
}
.appendix-page tbody tr {
  transition: background 0.2s ease;
}
.appendix-page tbody tr:hover {
  background: var(--color-surface);
}
.appendix-page hr {
  border: none;
  border-top: 1px solid var(--color-border);
  margin: 40px 0;
}
.appendix-page code {
  font-family: var(--font-mono);
  font-size: 12px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 1px 6px;
  color: var(--color-amber);
}
.appendix-page pre {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 16px 20px;
  overflow-x: auto;
  margin: 16px 0;
}
.appendix-page pre code {
  background: none;
  border: none;
  padding: 0;
  font-size: 12px;
  color: var(--color-text-secondary);
}
.appendix-page a:not(.appendix-back) {
  color: var(--color-accent);
  text-decoration: none;
  transition: color 0.2s ease;
  word-break: break-all;
}
.appendix-page a:not(.appendix-back):hover {
  color: var(--color-core);
  text-decoration: underline;
}
/* Tool UI screenshots */
.tool-screenshot {
  margin: 16px 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--color-surface);
}
.tool-screenshot img,
.tool-screenshot video {
  width: 100%;
  display: block;
}
.tool-screenshot figcaption {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--color-text-faint);
  padding: 8px 12px;
  text-align: center;
  letter-spacing: 0.02em;
  border-top: 1px solid var(--color-border);
}

.appendix-diagram {
  margin: 32px 0;
  text-align: center;
}
.appendix-diagram img {
  max-width: 100%;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}
.appendix-diagram figcaption {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-text-faint);
  margin-top: 10px;
  letter-spacing: 0.02em;
}

/* ---- Appendix Overlay (SPA transitions) ---- */
.appendix-overlay {
  position: fixed;
  top: 0;
  left: var(--sidebar-width);
  right: 0;
  bottom: 0;
  z-index: 50;
  background: var(--color-bg);
  background-image: url("data:image/svg+xml,%3Csvg width='20' height='20' xmlns='http://www.w3.org/2000/svg'%3E%3Ccircle cx='10' cy='10' r='0.5' fill='%2321262d' fill-opacity='0.5'/%3E%3C/svg%3E");
  background-size: 20px 20px;
  overflow-y: auto;
  overflow-x: hidden;
  overscroll-behavior: contain;
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}
.appendix-overlay.active {
  opacity: 1;
  visibility: visible;
  pointer-events: auto;
}
.appendix-overlay.expanding {
  animation: appendix-expand 0.5s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.appendix-overlay.collapsing {
  pointer-events: none;
  animation: appendix-collapse 0.38s cubic-bezier(0.4, 0, 0.2, 1) forwards;
}

@keyframes appendix-expand {
  from {
    opacity: 0;
    clip-path: inset(var(--clip-top, 30%) var(--clip-right, 5%) var(--clip-bottom, 30%) var(--clip-left, 5%) round 6px);
  }
  to {
    opacity: 1;
    clip-path: inset(0% 0% 0% 0% round 0px);
  }
}
@keyframes appendix-collapse {
  from {
    opacity: 1;
    clip-path: inset(0% 0% 0% 0% round 0px);
  }
  to {
    opacity: 0;
    clip-path: inset(var(--clip-top, 30%) var(--clip-right, 5%) var(--clip-bottom, 30%) var(--clip-left, 5%) round 6px);
  }
}

/* Sidebar appendix mode */
.sidebar .nav-links-appendix {
  display: none;
  list-style: none;
  padding: 0;
  margin: 0;
}
.sidebar.appendix-mode .nav-links-main {
  display: none;
}
.sidebar.appendix-mode .nav-links-appendix {
  display: block;
  flex: 1;
  padding-bottom: 12px;
  overflow-y: auto;
  scrollbar-width: none;
}
.sidebar.appendix-mode .nav-links-appendix::-webkit-scrollbar { display: none; }

.nav-back-btn {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 12px 24px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-amber);
  text-decoration: none;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  border: none;
  border-bottom: 1px solid var(--color-border);
  cursor: pointer;
  background: var(--color-sidebar);
  width: 100%;
  text-align: left;
  flex-shrink: 0;
  transition: background var(--transition-base), color var(--transition-base);
}
.sidebar.appendix-mode .nav-back-btn {
  display: flex;
}
.nav-back-btn:hover {
  background: var(--color-sidebar-hover);
  color: var(--color-text);
}
.nav-back-btn svg {
  width: 14px;
  height: 14px;
  flex-shrink: 0;
}

.appendix-nav-title {
  display: block;
  padding: 16px 24px 8px;
  font-family: var(--font-mono);
  font-size: 9px;
  font-weight: 600;
  color: var(--color-text-faint);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

/* Appendix overlay badge positioning (no back link needed, sidebar handles it) */
.appendix-overlay .appendix-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 600;
  color: var(--color-amber);
  background: var(--color-amber-light);
  border: 1px solid var(--color-amber-border);
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  letter-spacing: 0.06em;
  margin-bottom: 16px;
}
.appendix-overlay .appendix-footer {
  margin-top: 60px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
  text-align: center;
}
.appendix-overlay .appendix-footer p {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-text-faint);
  letter-spacing: 0.02em;
}

/* ---- Footer ---- */
.site-footer {
  padding: 40px 48px;
  max-width: calc(var(--content-max) + 96px);
  margin: 0 auto;
  text-align: center;
  border-top: 1px solid var(--color-border);
}

.site-footer p {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-text-faint);
  letter-spacing: 0.02em;
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 1024px) {
  .theory-grid,
  .methods-overview,
  .properties-grid,
  .req-grid {
    grid-template-columns: 1fr;
  }

  .principles-grid,
  .category-grid,
  .explore-grid,
  .rq-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .sidebar {
    transform: translateX(-100%);
    transition: transform 0.3s ease;
  }

  .sidebar.open {
    transform: translateX(0);
  }

  .menu-toggle {
    display: flex;
  }

  .overlay.visible {
    display: block;
  }

  .content {
    margin-left: 0;
  }

  .appendix-overlay {
    left: 0;
  }

  .appendix-page {
    padding: 24px 20px 60px;
  }

  .hero {
    padding: 72px 24px 40px;
  }

  .hero h1 {
    font-size: 26px;
  }

  .section {
    padding: 40px 24px;
  }

  .comparison {
    flex-direction: column;
  }

  .comparison-arrow {
    transform: rotate(90deg);
  }
}

/* ============================================
   Diagram SVG Animations
   ============================================ */

.diagram-svg {
  width: 100%;
  height: auto;
  display: block;
  overflow: visible;
}

.diagram-wrap {
  margin: 32px 0;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  background: var(--color-surface);
  padding: 24px;
  overflow: hidden;
  transition: border-color var(--transition-base);
}
.diagram-wrap:hover {
  border-color: var(--color-text-faint);
}

.diagram-wrap figcaption {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-text-tertiary);
  margin-top: 16px;
  text-align: center;
  letter-spacing: 0.02em;
}

.diagram-img {
  width: 100%;
  height: auto;
  display: block;
  border-radius: var(--radius-sm);
}

/* Fade + slide up */
.diagram-svg .anim {
  opacity: 0;
  transform: translateY(14px);
  transition: opacity 0.55s ease, transform 0.55s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  transition-delay: calc(var(--d, 0) * 55ms);
}
.diagram-svg.in-view .anim {
  opacity: 1;
  transform: translateY(0);
}

/* Pop in (for circles/dots) */
.diagram-svg .pop {
  opacity: 0;
  transform: scale(0);
  transform-origin: center;
  transform-box: fill-box;
  transition: opacity 0.35s ease, transform 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
  transition-delay: calc(var(--d, 0) * 35ms);
}
.diagram-svg.in-view .pop {
  opacity: 1;
  transform: scale(1);
}

/* Line draw (for straight lines with known length) */
.diagram-svg .draw-line {
  stroke-dasharray: var(--len, 80);
  stroke-dashoffset: var(--len, 80);
  transition: stroke-dashoffset 0.6s ease;
  transition-delay: calc(var(--d, 0) * 55ms);
}
.diagram-svg.in-view .draw-line {
  stroke-dashoffset: 0;
}

/* Path draw (for computed-length paths) */
.diagram-svg .draw-path {
  transition: stroke-dashoffset 0.8s ease;
  transition-delay: calc(var(--d, 0) * 55ms);
}
.diagram-svg.in-view .draw-path {
  stroke-dashoffset: 0 !important;
}

/* Gentle pulse on key elements */
@keyframes soft-pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.55; }
}
.diagram-svg.in-view .pulse {
  animation: soft-pulse 2.8s ease-in-out infinite;
  animation-delay: 1.8s;
}

/* Glow ring */
@keyframes glow-ring {
  0%, 100% { r: 7; opacity: 0.3; }
  50% { r: 10; opacity: 0; }
}
.diagram-svg.in-view .glow {
  animation: glow-ring 2.5s ease-in-out infinite;
  animation-delay: 2s;
}

/* Bar grow from left */
.diagram-svg .bar-grow {
  transform: scaleX(0);
  transform-origin: left center;
  transform-box: fill-box;
  transition: transform 0.7s cubic-bezier(0.25, 0.46, 0.45, 0.94);
  transition-delay: calc(var(--d, 0) * 100ms);
}
.diagram-svg.in-view .bar-grow {
  transform: scaleX(1);
}

/* ---- Table note (outcome note below tables) ---- */
.table-note {
  margin-top: 1rem;
  padding: 0.75rem 1rem;
  background: var(--color-amber-light);
  border-left: 3px solid var(--color-amber);
  border-radius: var(--radius-sm);
  font-size: 0.875rem;
  line-height: 1.6;
  color: var(--color-text-secondary);
}

/* ---- Outcome card in req-grid ---- */
.outcome-card {
  border-left-color: var(--color-amber) !important;
  background: var(--color-amber-light) !important;
  border-color: var(--color-amber-border) !important;
}
.outcome-card h4 {
  color: var(--color-amber) !important;
}

/* ---- Wireframe grid ---- */
.wireframe-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1.5rem;
  margin: 1.5rem 0 2rem;
}
.wireframe-item {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  overflow: hidden;
}
.wireframe-item img {
  width: 100%;
  height: auto;
  display: block;
  background: var(--color-bg);
}
.wireframe-item figcaption {
  padding: 0.75rem 1rem;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--color-text-tertiary);
  text-align: center;
  border-top: 1px solid var(--color-border);
  letter-spacing: 0.02em;
}

/* ---- Constraints list ---- */
.constraints-list {
  list-style: none;
  padding: 0;
  margin: 0.75rem 0;
}
.constraints-list li {
  padding: 0.5rem 0 0.5rem 1.5rem;
  position: relative;
  font-size: 0.9375rem;
  color: var(--color-text-secondary);
  line-height: 1.6;
}
.constraints-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.85rem;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--color-text-tertiary);
}

/* ---- Scroll-triggered section entry animations ---- */
.js-ready .section {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}
.js-ready .section.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Stagger children within visible sections */
.js-ready .section.visible .finding-card,
.js-ready .section.visible .theory-card,
.js-ready .section.visible .method-card,
.js-ready .section.visible .property-card,
.js-ready .section.visible .principle-card,
.js-ready .section.visible .explore-card,
.js-ready .section.visible .req-card,
.js-ready .section.visible .appendix-item,
.js-ready .section.visible .question-item {
  animation: stagger-in 0.45s ease both;
}

/* Wireframes: triggered by their own IntersectionObserver, not the section */
.js-ready .wireframe-item {
  opacity: 0;
  transform: translateY(12px);
}
.js-ready .wireframe-item.wf-visible {
  animation: stagger-in 0.45s ease both;
  animation-delay: var(--wf-delay, 0ms);
}
.js-ready .section.visible .finding-card:nth-child(1),
.js-ready .section.visible .theory-card:nth-child(1),
.js-ready .section.visible .method-card:nth-child(1),
.js-ready .section.visible .property-card:nth-child(1),
.js-ready .section.visible .principle-card:nth-child(1),
.js-ready .section.visible .explore-card:nth-child(1),
.js-ready .section.visible .req-card:nth-child(1) { animation-delay: 0ms; }

.js-ready .section.visible .finding-card:nth-child(2),
.js-ready .section.visible .theory-card:nth-child(2),
.js-ready .section.visible .method-card:nth-child(2),
.js-ready .section.visible .property-card:nth-child(2),
.js-ready .section.visible .principle-card:nth-child(2),
.js-ready .section.visible .explore-card:nth-child(2),
.js-ready .section.visible .req-card:nth-child(2) { animation-delay: 60ms; }

.js-ready .section.visible .finding-card:nth-child(3),
.js-ready .section.visible .theory-card:nth-child(3),
.js-ready .section.visible .method-card:nth-child(3),
.js-ready .section.visible .property-card:nth-child(3),
.js-ready .section.visible .principle-card:nth-child(3),
.js-ready .section.visible .explore-card:nth-child(3),
.js-ready .section.visible .req-card:nth-child(3) { animation-delay: 120ms; }

.js-ready .section.visible .finding-card:nth-child(4),
.js-ready .section.visible .req-card:nth-child(4) { animation-delay: 180ms; }

@keyframes stagger-in {
  from {
    opacity: 0;
    transform: translateY(12px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ---- Wireframe hover ---- */
.wireframe-item img {
  transition: transform 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}
.wireframe-item:hover img {
  transform: scale(1.01);
}
.wireframe-item {
  transition: border-color var(--transition-base);
}
.wireframe-item:hover {
  border-color: var(--color-text-faint);
}

/* ---- Refined table rows ---- */
tbody tr {
  transition: background var(--transition-base);
}
tbody tr:hover {
  background: var(--color-surface);
}

/* ---- Comparison card hover ---- */
.comparison-item {
  transition: border-color var(--transition-base);
}
.comparison-item:hover {
  border-color: var(--color-text-faint);
}

/* ---- Image lightbox ---- */
.diagram-img,
.wireframe-item img {
  cursor: zoom-in;
}

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 1000;
  background: rgba(0, 0, 0, 0.88);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: zoom-out;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.25s ease, visibility 0.25s ease;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.lightbox.active {
  opacity: 1;
  visibility: visible;
}

.lightbox img {
  max-width: 92vw;
  max-height: 92vh;
  object-fit: contain;
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  transform: scale(0.95);
  transition: transform 0.3s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

.lightbox.active img {
  transform: scale(1);
}

.lightbox-close {
  position: absolute;
  top: 20px;
  right: 24px;
  width: 36px;
  height: 36px;
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.15);
  border-radius: 50%;
  color: #fff;
  font-size: 18px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s;
}

.lightbox-close:hover {
  background: rgba(255, 255, 255, 0.2);
}