/* ==========================================================================
   ACS Framework — Documentary & Canonical Archive Stylesheet
   Self-contained, zero-external-dependency responsive editorial layout.
   Supports automatic prefers-color-scheme (light/dark) + manual toggle.
   ========================================================================== */

:root {
  color-scheme: light dark;
  --bg: #f7f5f0;
  --bg-elevated: #ffffff;
  --bg-subtle: #efeae0;
  --bg-canvas: #0b101d;
  --fg: #141923;
  --fg-muted: #4a5568;
  --fg-subtle: #697586;
  --border: #d8d2c5;
  --border-strong: #b8b09f;
  --accent: #0f62fe;
  --accent-soft: rgba(15, 98, 254, 0.10);
  --cyan: #0891b2;
  --amber: #b45309;
  --emerald: #047857;
  --rose: #be123c;
  --violet: #6d28d9;
  --t1-bg: rgba(4, 120, 87, 0.12);
  --t1-fg: #065f46;
  --t1-border: rgba(4, 120, 87, 0.35);
  --t2-bg: rgba(8, 145, 178, 0.12);
  --t2-fg: #0e7490;
  --t2-border: rgba(8, 145, 178, 0.35);
  --t3-bg: rgba(180, 83, 9, 0.12);
  --t3-fg: #92400e;
  --t3-border: rgba(180, 83, 9, 0.35);
  --t4-bg: rgba(190, 18, 60, 0.12);
  --t4-fg: #9f1239;
  --t4-border: rgba(190, 18, 60, 0.38);
  --shadow-sm: 0 1px 3px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 8px 24px rgba(15, 23, 42, 0.08);
  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 14px;
  --font-serif: "Iowan Old Style", "Palatino Linotype", "Book Antiqua", Palatino, Georgia, serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, "Liberation Mono", monospace;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #080c16;
    --bg-elevated: #0f1626;
    --bg-subtle: #151e32;
    --bg-canvas: #070b14;
    --fg: #e6edf7;
    --fg-muted: #a3b1c6;
    --fg-subtle: #78879e;
    --border: #202c44;
    --border-strong: #324364;
    --accent: #38bdf8;
    --accent-soft: rgba(56, 189, 248, 0.12);
    --cyan: #22d3ee;
    --amber: #f59e0b;
    --emerald: #34d399;
    --rose: #fb7185;
    --violet: #a78bfa;
    --t1-bg: rgba(52, 211, 153, 0.13);
    --t1-fg: #6ee7b7;
    --t1-border: rgba(52, 211, 153, 0.38);
    --t2-bg: rgba(34, 211, 238, 0.13);
    --t2-fg: #67e8f9;
    --t2-border: rgba(34, 211, 238, 0.38);
    --t3-bg: rgba(245, 158, 11, 0.14);
    --t3-fg: #fcd34d;
    --t3-border: rgba(245, 158, 11, 0.38);
    --t4-bg: rgba(251, 113, 133, 0.14);
    --t4-fg: #fda4af;
    --t4-border: rgba(251, 113, 133, 0.42);
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.35);
    --shadow-md: 0 10px 28px rgba(0, 0, 0, 0.45);
  }
}

html[data-theme="dark"] {
  --bg: #080c16;
  --bg-elevated: #0f1626;
  --bg-subtle: #151e32;
  --bg-canvas: #070b14;
  --fg: #e6edf7;
  --fg-muted: #a3b1c6;
  --fg-subtle: #78879e;
  --border: #202c44;
  --border-strong: #324364;
  --accent: #38bdf8;
  --accent-soft: rgba(56, 189, 248, 0.12);
  --cyan: #22d3ee;
  --amber: #f59e0b;
  --emerald: #34d399;
  --rose: #fb7185;
  --violet: #a78bfa;
  --t1-bg: rgba(52, 211, 153, 0.13);
  --t1-fg: #6ee7b7;
  --t1-border: rgba(52, 211, 153, 0.38);
  --t2-bg: rgba(34, 211, 238, 0.13);
  --t2-fg: #67e8f9;
  --t2-border: rgba(34, 211, 238, 0.38);
  --t3-bg: rgba(245, 158, 11, 0.14);
  --t3-fg: #fcd34d;
  --t3-border: rgba(245, 158, 11, 0.38);
  --t4-bg: rgba(251, 113, 133, 0.14);
  --t4-fg: #fda4af;
  --t4-border: rgba(251, 113, 133, 0.42);
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.35);
  --shadow-md: 0 10px 28px rgba(0, 0, 0, 0.45);
}

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

html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  max-width: 100%;
  overflow-x: hidden;
  background-color: var(--bg);
  color: var(--fg);
  font-family: var(--font-sans);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

img, svg, canvas, video {
  max-width: 100%;
  display: block;
}

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

a:hover {
  text-decoration: underline;
}

code, pre, .mono {
  font-family: var(--font-mono);
  font-size: 0.88em;
  overflow-wrap: anywhere;
}

.container {
  width: 100%;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

/* Header & Navigation */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--bg-elevated);
  border-bottom: 1px solid var(--border);
  backdrop-filter: blur(10px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.75rem 0;
  flex-wrap: wrap;
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  font-weight: 700;
  color: var(--fg);
  text-decoration: none;
}

.brand-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  border-radius: var(--radius-sm);
  background: var(--accent-soft);
  border: 1px solid var(--accent);
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.85rem;
  font-weight: 700;
  flex-shrink: 0;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.brand-title {
  font-size: 0.95rem;
  letter-spacing: -0.01em;
}

.brand-sub {
  font-size: 0.72rem;
  color: var(--fg-muted);
  font-weight: 500;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  flex-wrap: wrap;
}

.site-nav a {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--fg-muted);
  padding: 0.3rem 0.55rem;
  border-radius: var(--radius-sm);
  transition: background 0.15s, color 0.15s;
}

.site-nav a:hover {
  background: var(--bg-subtle);
  color: var(--fg);
  text-decoration: none;
}

.theme-btn {
  background: var(--bg-subtle);
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.32rem 0.65rem;
  font-size: 0.78rem;
  font-family: var(--font-mono);
  cursor: pointer;
}

.theme-btn:hover {
  border-color: var(--border-strong);
}

/* Hero Section */
.hero {
  padding: 3rem 0 2.25rem;
  border-bottom: 1px solid var(--border);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 0.28rem 0.65rem;
  border-radius: 999px;
  margin-bottom: 1rem;
}

.hero h1 {
  font-family: var(--font-serif);
  font-size: clamp(1.85rem, 4vw, 3.1rem);
  line-height: 1.15;
  margin: 0 0 1rem;
  letter-spacing: -0.02em;
}

.hero-lead {
  font-size: clamp(1rem, 1.6vw, 1.2rem);
  color: var(--fg-muted);
  max-width: 78ch;
  margin: 0 0 1.5rem;
}

.hero-equation-box {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-left: 4px solid var(--accent);
  border-radius: var(--radius-md);
  padding: 1rem 1.25rem;
  margin: 1.5rem 0;
  box-shadow: var(--shadow-sm);
  overflow-x: auto;
}

.hero-equation-label {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--fg-subtle);
  margin-bottom: 0.4rem;
}

.metrics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 170px), 1fr));
  gap: 0.85rem;
  margin: 1.75rem 0;
}

.metric-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 0.9rem 1rem;
  box-shadow: var(--shadow-sm);
}

.metric-value {
  font-family: var(--font-mono);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--fg);
  line-height: 1.2;
}

.metric-label {
  font-size: 0.8rem;
  color: var(--fg-muted);
  margin-top: 0.2rem;
}

/* Scope & Non-Claims Banner */
.scope-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 300px), 1fr));
  gap: 1rem;
  margin-top: 1.5rem;
}

.scope-panel {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.1rem 1.25rem;
}

.scope-panel.non-claims {
  border-top: 3px solid var(--rose);
}

.scope-panel.verified-spine {
  border-top: 3px solid var(--emerald);
}

.scope-panel h3 {
  margin: 0 0 0.65rem;
  font-size: 0.98rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.scope-panel ul {
  margin: 0;
  padding-left: 1.15rem;
  font-size: 0.88rem;
  color: var(--fg-muted);
}

.scope-panel li + li {
  margin-top: 0.4rem;
}

/* Section Layout */
.section {
  padding: 3rem 0;
  border-bottom: 1px solid var(--border);
}

.section-header {
  margin-bottom: 1.75rem;
}

.section-kicker {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
  margin-bottom: 0.35rem;
}

.section-title {
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 2.8vw, 2.2rem);
  margin: 0 0 0.5rem;
  line-height: 1.2;
}

.section-desc {
  color: var(--fg-muted);
  max-width: 76ch;
  margin: 0;
  font-size: 0.96rem;
}

/* Tier Badges */
.tier-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-family: var(--font-mono);
  font-size: 0.73rem;
  font-weight: 700;
  padding: 0.18rem 0.52rem;
  border-radius: 999px;
  border: 1px solid transparent;
  white-space: nowrap;
}

.tier-T1 {
  background: var(--t1-bg);
  color: var(--t1-fg);
  border-color: var(--t1-border);
}

.tier-T2 {
  background: var(--t2-bg);
  color: var(--t2-fg);
  border-color: var(--t2-border);
}

.tier-T3 {
  background: var(--t3-bg);
  color: var(--t3-fg);
  border-color: var(--t3-border);
}

.tier-T4 {
  background: var(--t4-bg);
  color: var(--t4-fg);
  border-color: var(--t4-border);
}

/* Interactive 3D Scene Studio */
.scenes-stack {
  display: flex;
  flex-direction: column;
  gap: 1.75rem;
}

.scene-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(0, 1fr);
}

@media (max-width: 920px) {
  .scene-card {
    grid-template-columns: 1fr;
  }
}

.scene-viewport {
  position: relative;
  min-height: 360px;
  background: var(--bg-canvas);
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.scene-viewport canvas {
  width: 100% !important;
  height: 100% !important;
  display: block;
}

.scene-fallback {
  width: 100%;
  height: 100%;
  object-fit: contain;
  display: none;
}

.scene-viewport[data-state="fallback"] .scene-fallback {
  display: block;
}

.scene-viewport[data-state="fallback"] canvas {
  display: none !important;
}

.scene-hud {
  position: absolute;
  top: 0.75rem;
  left: 0.75rem;
  right: 0.75rem;
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 0.5rem;
  pointer-events: none;
  flex-wrap: wrap;
}

.scene-chip {
  background: rgba(10, 15, 28, 0.82);
  color: #e2e8f0;
  border: 1px solid rgba(148, 163, 184, 0.28);
  padding: 0.25rem 0.55rem;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.72rem;
}

.scene-panel {
  padding: 1.35rem;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 1rem;
  border-left: 1px solid var(--border);
}

@media (max-width: 920px) {
  .scene-panel {
    border-left: none;
    border-top: 1px solid var(--border);
  }
}

.scene-panel h3 {
  margin: 0.35rem 0 0.45rem;
  font-family: var(--font-serif);
  font-size: 1.3rem;
}

.scene-panel p {
  margin: 0 0 0.75rem;
  font-size: 0.9rem;
  color: var(--fg-muted);
}

.scene-math {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.6rem 0.8rem;
  overflow-x: auto;
  font-size: 0.88rem;
}

.scene-controls {
  display: flex;
  flex-direction: column;
  gap: 0.65rem;
  padding-top: 0.65rem;
  border-top: 1px solid var(--border);
}

.control-row {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
}

.control-row label {
  display: flex;
  justify-content: space-between;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--fg-muted);
}

.control-row input[type="range"] {
  width: 100%;
  accent-color: var(--accent);
}

.readout-bar {
  font-family: var(--font-mono);
  font-size: 0.76rem;
  color: var(--fg);
  background: var(--bg-subtle);
  padding: 0.45rem 0.65rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
}

/* Core Trilogy & Mathematical Spine Cards */
.trilogy-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 340px), 1fr));
  gap: 1.25rem;
}

.spine-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.25rem;
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.spine-card-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 0.5rem;
}

.spine-card h3 {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 1.15rem;
}

.spine-card p {
  margin: 0;
  font-size: 0.88rem;
  color: var(--fg-muted);
}

.equation-block {
  background: var(--bg-subtle);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.65rem 0.75rem;
  overflow-x: auto;
  font-size: 0.86rem;
}

.caveat-note {
  font-size: 0.8rem;
  color: var(--fg-muted);
  border-left: 3px solid var(--amber);
  padding-left: 0.65rem;
  margin-top: auto;
}

/* Filter Controls */
.filter-toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.25rem;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 0.75rem 1rem;
}

.pill-group {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
}

.filter-pill {
  background: var(--bg-subtle);
  color: var(--fg-muted);
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 0.3rem 0.7rem;
  font-size: 0.78rem;
  font-family: var(--font-mono);
  cursor: pointer;
  transition: all 0.15s;
}

.filter-pill.active,
.filter-pill:hover {
  background: var(--accent-soft);
  color: var(--accent);
  border-color: var(--accent);
}

.search-input {
  background: var(--bg);
  color: var(--fg);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 0.42rem 0.75rem;
  font-size: 0.85rem;
  min-width: min(100%, 240px);
}

/* Claims & Elimination Ledger Cards */
.claims-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 340px), 1fr));
  gap: 1rem;
}

.claim-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.1rem;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  box-shadow: var(--shadow-sm);
}

.claim-card[data-tier="T4"] {
  border-left: 4px solid var(--rose);
}

.claim-card[data-tier="T1"] {
  border-left: 4px solid var(--emerald);
}

.claim-card[data-tier="T2"] {
  border-left: 4px solid var(--cyan);
}

.claim-card[data-tier="T3"] {
  border-left: 4px solid var(--amber);
}

.claim-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.claim-id {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  color: var(--fg-subtle);
}

.claim-title {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
}

.claim-summary {
  margin: 0;
  font-size: 0.86rem;
  color: var(--fg-muted);
}

.claim-footer {
  margin-top: auto;
  padding-top: 0.55rem;
  border-top: 1px dashed var(--border);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
  font-size: 0.76rem;
  font-family: var(--font-mono);
  color: var(--fg-subtle);
}

/* 35-Paper Canonical Catalog */
.catalog-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 330px), 1fr));
  gap: 1rem;
}

.paper-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.1rem;
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  box-shadow: var(--shadow-sm);
}

.paper-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.paper-group-tag {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  padding: 0.15rem 0.5rem;
  border-radius: var(--radius-sm);
  background: var(--bg-subtle);
  color: var(--fg-muted);
  border: 1px solid var(--border);
}

.paper-date {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--fg-subtle);
}

.paper-title {
  margin: 0;
  font-family: var(--font-serif);
  font-size: 1.05rem;
  line-height: 1.3;
}

.paper-summary {
  margin: 0;
  font-size: 0.85rem;
  color: var(--fg-muted);
}

.paper-links {
  margin-top: auto;
  padding-top: 0.65rem;
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
}

.btn-link {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  font-family: var(--font-mono);
  font-size: 0.76rem;
  font-weight: 600;
  padding: 0.32rem 0.65rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--bg-subtle);
  color: var(--fg);
  text-decoration: none;
}

.btn-link.primary {
  background: var(--accent-soft);
  border-color: var(--accent);
  color: var(--accent);
}

.btn-link:hover {
  text-decoration: none;
  border-color: var(--accent);
}

/* Timeline */
.timeline-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 230px), 1fr));
  gap: 1rem;
}

.timeline-step {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-top: 3px solid var(--accent);
  border-radius: var(--radius-md);
  padding: 1.1rem;
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.timeline-period {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--accent);
}

.timeline-title {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
}

.timeline-summary {
  margin: 0;
  font-size: 0.84rem;
  color: var(--fg-muted);
}

/* Author & Provenance Section */
.provenance-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(min(100%, 340px), 1fr));
  gap: 1.25rem;
}

.provenance-card {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.35rem;
}

.provenance-card h3 {
  margin: 0 0 0.65rem;
  font-family: var(--font-serif);
  font-size: 1.2rem;
}

.provenance-card p {
  margin: 0 0 0.75rem;
  font-size: 0.89rem;
  color: var(--fg-muted);
}

.site-footer {
  padding: 2.25rem 0;
  background: var(--bg-elevated);
  font-size: 0.84rem;
  color: var(--fg-muted);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 1.5rem;
  flex-wrap: wrap;
}

.katex-display {
  overflow-x: auto;
  overflow-y: hidden;
  max-width: 100%;
  margin: 0.4rem 0 !important;
}