/* ==========================================================================
   GPT以後のLLMの歴史 — Style Sheet
   ========================================================================== */

:root {
  --paper: #f4efe4;
  --paper-strong: rgba(252, 248, 240, 0.86);
  --paper-soft: rgba(255, 252, 246, 0.56);
  --ink: #171512;
  --muted: #605c54;
  --muted-soft: #8b857b;
  --line: rgba(23, 21, 18, 0.12);
  --line-strong: rgba(23, 21, 18, 0.22);
  --accent: #2b6a4a;
  --accent-soft: rgba(43, 106, 74, 0.12);
  --accent-2: #4d5652;
  --accent-3: #bba67d;
  --shadow: 0 18px 50px rgba(54, 43, 26, 0.1);
  --radius-xl: 30px;
  --radius-lg: 22px;
  --radius-md: 16px;
  --content-max: 720px;
  --graph-max: 430px;
}

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background:
    radial-gradient(circle at top left, rgba(255, 255, 255, 0.68), transparent 32%),
    radial-gradient(circle at bottom right, rgba(187, 166, 125, 0.16), transparent 28%),
    linear-gradient(180deg, #f8f3e9 0%, var(--paper) 48%, #efe8dc 100%);
  font-family: "Manrope", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

h1,
h2,
h3 {
  margin: 0;
  font-family: "Cormorant Garamond", Georgia, serif;
  font-weight: 500;
  line-height: 1.06;
  letter-spacing: -0.01em;
}

h1 {
  font-size: clamp(2.9rem, 5vw, 4.75rem);
}

h2 {
  font-size: clamp(2.05rem, 3.2vw, 3.05rem);
}

h3 {
  font-size: clamp(1.55rem, 2vw, 2rem);
}

p {
  margin: 0 0 1rem;
  max-width: 39rem;
}

a {
  color: var(--accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.14em;
}

.main-grid {
  display: grid;
  grid-template-areas:
    ". header header ."
    ". toc content graph"
    ". toc content graph";
  grid-template-columns:
    minmax(18px, 1fr)
    minmax(96px, 132px)
    minmax(0, var(--content-max))
    minmax(320px, var(--graph-max))
    minmax(18px, 1fr);
  column-gap: clamp(18px, 2.5vw, 40px);
  width: min(100%, 1520px);
  margin-inline: auto;
  padding: 22px 0 72px;
}

.site-header {
  padding: 28px 0 28px;
}

.site-dek {
  margin-top: 1.2rem;
  color: var(--muted);
  font-size: clamp(1rem, 1.15vw, 1.1rem);
  line-height: 1.85;
  max-width: 41rem;
}

.site-wip {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 0.85rem;
  padding: 0.4rem 0.9rem;
  border-radius: 999px;
  background: rgba(23, 21, 18, 0.05);
  color: var(--muted);
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.intro-block {
  padding: 0.25rem 0 1.5rem;
}

.intro-block p {
  color: var(--muted);
  font-size: 0.98rem;
}

.tab-box {
  margin-top: 1.25rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-md);
  background: rgba(255, 252, 246, 0.42);
  overflow: clip;
}

.tab-box summary {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.78rem 1rem;
  list-style: none;
  cursor: pointer;
  font-size: 0.98rem;
  color: var(--ink);
}

.tab-box summary::-webkit-details-marker {
  display: none;
}

.tab-box summary::before {
  content: "▶";
  font-size: 0.78rem;
  transform: translateY(-0.02em);
}

.tab-box[open] summary::before {
  content: "▼";
}

.tab-panel {
  padding: 0 1rem 1rem;
  color: var(--muted);
  font-size: 0.94rem;
}

.history-section {
  padding: clamp(3.8rem, 8vw, 6.8rem) 0;
  border-bottom: 1px solid var(--line);
  scroll-margin-top: 42vh;
}

.history-section:last-child {
  padding-bottom: 8rem;
  border-bottom: none;
}

.history-section time {
  display: inline-flex;
  align-items: center;
  margin-bottom: 0.65rem;
  padding: 0.28rem 0.7rem;
  border-radius: 999px;
  background: rgba(23, 21, 18, 0.05);
  color: var(--muted);
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.72rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.history-section h2 {
  max-width: 40rem;
  margin-bottom: 1rem;
}

.history-section p {
  font-size: clamp(1rem, 1.14vw, 1.08rem);
}

.graph-shell {
  min-width: 0;
}

.sticky-chart-container {
  position: sticky;
  top: 28px;
  width: 100%;
  padding-top: 0.35rem;
  background: transparent;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.date-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.18rem;
  min-height: 2rem;
  margin-bottom: 0.7rem;
  padding: 0.34rem 0.62rem;
  border-radius: 0.42rem;
  background: #0f0f0f;
  color: #fff;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.76rem;
  letter-spacing: 0.06em;
}

.month-slot {
  position: relative;
  width: 2.5rem;
  height: 1rem;
  overflow: hidden;
}

.month-text {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: flex-start;
  transition: transform 320ms cubic-bezier(0.22, 1, 0.36, 1), opacity 320ms ease;
}

.month-text-next {
  transform: translateY(100%);
  opacity: 0;
}

.sticky-chart-container.is-animating .month-text {
  transform: translateY(-100%);
  opacity: 0;
}

.sticky-chart-container.is-animating .month-text-next {
  transform: translateY(0);
  opacity: 1;
}

.year-slot {
  display: inline-flex;
  align-items: center;
  gap: 0.02rem;
}

.digit-column {
  position: relative;
  width: 0.62rem;
  height: 1rem;
  overflow: hidden;
}

.digit-stack {
  display: flex;
  flex-direction: column;
  transition: transform 420ms cubic-bezier(0.2, 0.9, 0.2, 1);
}

.digit-stack span {
  display: block;
  height: 1rem;
  line-height: 1rem;
}

.chart-stage {
  position: relative;
  margin-bottom: 0.85rem;
  padding: 0.2rem 0 0;
  background:
    radial-gradient(circle at top right, rgba(43, 106, 74, 0.08), transparent 42%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.22), rgba(244, 238, 228, 0));
}

.chart-source {
  margin: 0 0 0.7rem;
  color: rgba(96, 92, 84, 0.54);
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.54rem;
  letter-spacing: 0.01em;
  line-height: 1.35;
  max-width: 30ch;
}

.chart-source code {
  font-size: 0.92em;
  color: inherit;
}

.chart-source a {
  color: rgba(96, 92, 84, 0.7);
  text-decoration-thickness: 0.5px;
}

#history-chart {
  display: block;
  width: 100%;
  height: auto;
}

.panel-anim {
  display: grid;
  gap: 0.8rem;
  transition: opacity 220ms ease, transform 220ms ease;
}

.sticky-chart-container.is-switching .panel-anim {
  opacity: 0.18;
  transform: translateY(12px);
}

.micro-label {
  margin: 0;
  color: var(--muted-soft);
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.61rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.panel-meta-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 110px;
  gap: 0.85rem;
  align-items: center;
}

.panel-meta-row-benchmarks {
  grid-template-columns: minmax(0, 1fr);
}

.capability-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.42rem 0.52rem;
}

.capability-chip {
  display: flex;
  align-items: center;
  min-width: 0;
  height: 1.72rem;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.69rem;
  letter-spacing: 0.03em;
}

.capability-chip-flag {
  width: 1.7rem;
  height: 100%;
  background: #111;
  flex: 0 0 auto;
}

.capability-chip-label {
  flex: 1;
  min-width: 0;
  display: flex;
  align-items: center;
  padding: 0 0.55rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  background: rgba(17, 17, 17, 0.08);
  color: var(--ink);
}

.capability-chip.is-active .capability-chip-label {
  background: rgba(43, 106, 74, 0.9);
  color: #fff;
}

.capability-chip.is-mid .capability-chip-label {
  background: rgba(43, 106, 74, 0.28);
  color: #163021;
}

.toc-shell,
.section-nav {
  height: 100%;
}

.toc-sticky {
  position: sticky;
  top: 30px;
  height: calc(100vh - 60px);
  display: flex;
  align-items: center;
}

.toc-svg {
  width: 132px;
  height: 420px;
  display: block;
  cursor: pointer;
}

.toc-label {
  fill: var(--muted-soft);
  opacity: 0;
  transition: opacity 180ms ease, fill 180ms ease;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 11px;
  letter-spacing: 0.05em;
}

.toc-dot-group:hover .toc-label,
.toc-dot-group:focus-within .toc-label,
.toc-dot-group.active .toc-label {
  opacity: 1;
}

.toc-dot-group.active .toc-label {
  fill: var(--ink);
}

.toc-dot {
  transition: transform 180ms ease, fill 180ms ease;
  transform-origin: center;
}

.toc-dot-group:hover .toc-dot {
  transform: scale(1.08);
}

.history-section details {
  margin-top: 1rem;
}

@media (min-width: 1440px) {
  .toc-label {
    opacity: 1;
  }
}

@media (max-width: 1220px) {
  .main-grid {
    grid-template-areas:
      ". header graph ."
      ". content graph ."
      ". content graph .";
    grid-template-columns:
      minmax(18px, 1fr)
      minmax(0, var(--content-max))
      minmax(300px, 392px)
      minmax(18px, 1fr);
  }

  .toc-shell,
  .section-nav {
    display: none;
  }
}

@media (max-width: 920px) {
  .main-grid {
    grid-template-areas:
      ". header ."
      ". graph ."
      ". content .";
    grid-template-columns: 14px minmax(0, 1fr) 14px;
    row-gap: 1.2rem;
    padding-top: 8px;
  }

  .site-header {
    padding: 1.4rem 0 0.35rem;
  }

  .sticky-chart-container {
    position: static;
    padding-top: 0;
  }

  .history-section {
    padding: 3.25rem 0;
    scroll-margin-top: 16vh;
  }
}

@media (max-width: 1100px) {
  .llm-demo-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  body {
    font-size: 15px;
  }

  h1 {
    font-size: clamp(2.45rem, 13vw, 3.2rem);
  }

  h2 {
    font-size: clamp(1.95rem, 10vw, 2.5rem);
  }

  .site-dek,
  .history-section p,
  .info-summary {
    font-size: 0.98rem;
  }

  .chart-stage {
    padding-inline: 0;
  }

  .capability-grid {
    grid-template-columns: 1fr;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .toc-label,
  .toc-dot {
    transition: none;
  }
}

/* ==========================================================================
   Additional styles for full article
   ========================================================================== */

/* --- Subsection headings (h3) inside history-section --- */
.history-section h3 {
  margin-top: 2.8rem;
  margin-bottom: 0.85rem;
  font-size: clamp(1.35rem, 1.8vw, 1.7rem);
  color: var(--ink);
}

.history-section h3:first-of-type {
  margin-top: 1.8rem;
}

/* --- Source reference links --- */
.ref {
  display: inline-flex;
  align-items: center;
  gap: 0.15em;
  font-size: 0.72em;
  vertical-align: super;
  line-height: 1;
  text-decoration: none;
  color: var(--accent);
  opacity: 0.72;
  transition: opacity 160ms ease;
}

.ref:hover {
  opacity: 1;
}

.ref::before {
  content: "[";
}

.ref::after {
  content: "]";
}

/* Source level badges */
.ref[data-level="4"]::after { content: " Lv4]"; }
.ref[data-level="3"]::after { content: " Lv3]"; }
.ref[data-level="2"]::after { content: " Lv2]"; }
.ref[data-level="1"]::after { content: " Lv1]"; }

/* --- Disclaimer block --- */
.disclaimer-block {
  margin: 1.2rem 0 2rem;
  padding: 1rem 1.25rem;
  border-left: 3px solid var(--accent-3);
  background: rgba(187, 166, 125, 0.08);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  font-size: 0.9rem;
  color: var(--muted);
  line-height: 1.7;
}

.disclaimer-block p {
  font-size: 0.9rem;
  color: var(--muted);
}

.disclaimer-block strong {
  color: var(--ink);
}

/* --- Column (コラム) boxes --- */
.column-box {
  margin: 2rem 0;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-md);
  background: rgba(255, 252, 246, 0.42);
  overflow: clip;
}

.column-box summary {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  padding: 0.85rem 1.1rem;
  list-style: none;
  cursor: pointer;
  font-size: 0.98rem;
  font-weight: 600;
  color: var(--accent-2);
}

.column-box summary::-webkit-details-marker {
  display: none;
}

.column-box summary::before {
  content: "📖";
  font-size: 0.92rem;
}

.column-box summary::after {
  content: "▶";
  font-size: 0.68rem;
  margin-left: auto;
  transition: transform 200ms ease;
}

.column-box[open] summary::after {
  transform: rotate(90deg);
}

.column-body {
  padding: 0 1.2rem 1.2rem;
  font-size: 0.95rem;
  line-height: 1.85;
  color: var(--ink);
}

.column-body p {
  font-size: 0.95rem;
  max-width: 39rem;
}

.column-body h4 {
  margin: 1.2rem 0 0.5rem;
  font-family: "Manrope", system-ui, sans-serif;
  font-size: 1rem;
  font-weight: 600;
  color: var(--ink);
}

/* --- Bottleneck summary blocks --- */
.bottleneck-block {
  margin: 2.5rem 0 0.5rem;
  padding: 1.1rem 1.25rem;
  border-radius: var(--radius-md);
  background: rgba(23, 21, 18, 0.035);
  border: 1px solid var(--line);
  font-size: 0.94rem;
  color: var(--muted);
  line-height: 1.8;
}

.bottleneck-block p {
  font-size: 0.94rem;
  color: var(--muted);
}

.bottleneck-block strong {
  color: var(--ink);
}

/* --- Emphasis/callout within text --- */
.text-highlight {
  background: linear-gradient(180deg, transparent 60%, rgba(187, 166, 125, 0.22) 60%);
  padding: 0 0.15em;
}

/* --- Section 5 separation --- */
.sec5-separator {
  margin: 4rem 0 2rem;
  padding: 1.5rem 0;
  border-top: 2px solid var(--line-strong);
  text-align: center;
  color: var(--muted);
  font-size: 0.88rem;
  font-style: italic;
}

/* --- Source list at the end --- */
.source-list {
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid var(--line);
}

.source-list h3 {
  font-size: 1.1rem;
  margin-bottom: 1rem;
}

.source-list ol {
  padding-left: 1.6rem;
  font-size: 0.85rem;
  line-height: 1.7;
  color: var(--muted);
}

.source-list li {
  margin-bottom: 0.35rem;
}

.source-list a {
  word-break: break-all;
}

/* Level badge in source list */
.level-badge {
  display: inline-block;
  padding: 0.1em 0.4em;
  border-radius: 4px;
  font-size: 0.75em;
  font-weight: 600;
  line-height: 1;
  vertical-align: middle;
  margin-right: 0.3em;
}

.level-badge[data-l="4"] { background: rgba(43,106,74,0.12); color: var(--accent); }
.level-badge[data-l="3"] { background: rgba(59,130,246,0.12); color: #2563eb; }
.level-badge[data-l="2"] { background: rgba(245,158,11,0.12); color: #b45309; }
.level-badge[data-l="1"] { background: rgba(139,133,123,0.12); color: var(--muted-soft); }

/* WIP notice styling update */
.site-wip {
  display: none;
}

/* --- Blockquote --- */
blockquote {
  margin: 1.5rem 0;
  padding: 0.8rem 1.2rem;
  border-left: 3px solid var(--accent-3);
  background: rgba(187, 166, 125, 0.06);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  font-size: 0.96rem;
  color: var(--muted);
}
blockquote p { margin: 0.4em 0; }
blockquote cite {
  display: block;
  margin-top: 0.5em;
  font-size: 0.85em;
  font-style: normal;
  color: var(--muted-soft);
}

blockquote iframe {
  display: block;
  width: 100%;
  max-width: 100%;
  aspect-ratio: 16 / 9;
  height: auto;
  margin-top: 0.8rem;
  border: 0;
  border-radius: 12px;
}

/* --- Footnote-style annotations --- */
.fn {
  font-size: 0.85rem;
  color: var(--muted);
  margin: 0.3rem 0 1.2rem;
  padding-left: 1em;
  border-left: 2px solid var(--line);
}

/* --- Inline figure / stat --- */
.stat-inline {
  display: inline-block;
  font-family: "IBM Plex Mono", monospace;
  font-weight: 500;
  color: var(--accent);
}

.article-figure {
  margin: 1.7rem 0 1.9rem;
  padding: 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.58), rgba(255, 252, 246, 0.4));
  box-shadow: 0 10px 24px rgba(54, 43, 26, 0.06);
}

.article-figure svg {
  display: block;
  width: 100%;
  height: auto;
}

.article-figure figcaption {
  margin-top: 0.75rem;
  font-size: 0.84rem;
  line-height: 1.65;
  color: var(--muted);
}

.inline-demo-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin: 1rem 0 0;
  padding: 0.7rem 1rem;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  background: rgba(43, 106, 74, 0.08);
  color: var(--accent-2);
  font: inherit;
  font-size: 0.94rem;
}

.inline-demo-button:not([disabled]) {
  cursor: pointer;
  transition: background 160ms ease, border-color 160ms ease;
}

.inline-demo-button:not([disabled]):hover {
  background: rgba(43, 106, 74, 0.16);
  border-color: var(--accent);
}

.inline-demo-button[disabled] {
  cursor: not-allowed;
  opacity: 0.72;
}

/* --- Scene 1 prompt modal --- */
.scene1-prompt-trigger {
  display: inline;
  margin: 0;
  padding: 0;
  border: 0;
  background: none;
  color: var(--accent);
  font: inherit;
  line-height: inherit;
  cursor: pointer;
  text-decoration: underline;
  text-decoration-thickness: 1px;
  text-underline-offset: 0.14em;
  transition: color 160ms ease, opacity 160ms ease;
}

.scene1-prompt-trigger:hover {
  color: #1e563b;
}

.scene1-prompt-trigger:focus-visible {
  outline: 2px solid rgba(43, 106, 74, 0.35);
  outline-offset: 4px;
  border-radius: 0.35rem;
}

body.scene1-chat-open {
  overflow: hidden;
}

.scene1-chat-modal[hidden] {
  display: none;
}

.scene1-chat-modal {
  position: fixed;
  inset: 0;
  z-index: 1200;
  display: grid;
  place-items: center;
  padding: 1.5rem;
}

.scene1-chat-modal__backdrop {
  position: absolute;
  inset: 0;
  background: rgba(15, 18, 20, 0.58);
  backdrop-filter: blur(10px);
}

.scene1-chat-modal__dialog {
  position: relative;
  width: min(840px, 100%);
  max-height: min(88vh, 960px);
  overflow: hidden;
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 1.6rem;
  background:
    radial-gradient(circle at top right, rgba(43, 106, 74, 0.13), transparent 30%),
    linear-gradient(180deg, rgba(32, 35, 40, 0.98) 0%, rgba(22, 25, 28, 0.98) 100%);
  box-shadow: 0 28px 90px rgba(0, 0, 0, 0.34);
  color: #f3f6f4;
}

.scene1-chat-modal__header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.1rem 1.25rem;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(255, 255, 255, 0.03);
}

.scene1-chat-modal__heading h3 {
  font-family: "Manrope", system-ui, sans-serif;
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: 0;
  color: #f8faf9;
}

.scene1-chat-modal__eyebrow {
  margin: 0 0 0.25rem;
  color: rgba(242, 246, 244, 0.62);
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.scene1-chat-modal__meta {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.scene1-chat-modal__model {
  display: inline-flex;
  align-items: center;
  padding: 0.3rem 0.65rem;
  border-radius: 999px;
  background: rgba(43, 106, 74, 0.2);
  color: #d8efe4;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.74rem;
}

.scene1-chat-modal__close {
  width: 2.3rem;
  height: 2.3rem;
  border: 0;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.08);
  color: #f7faf8;
  font: inherit;
  font-size: 1.2rem;
  line-height: 1;
  cursor: pointer;
  transition: background 160ms ease, transform 160ms ease;
}

.scene1-chat-modal__close:hover {
  background: rgba(255, 255, 255, 0.14);
  transform: translateY(-1px);
}

.scene1-chat-modal__close:focus-visible {
  outline: 2px solid rgba(123, 202, 157, 0.7);
  outline-offset: 2px;
}

.scene1-chat-thread {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-height: calc(88vh - 5.5rem);
  padding: 1.2rem;
  overflow: auto;
}

.scene1-chat-message--user {
  display: flex;
  justify-content: flex-end;
}

.scene1-chat-message--assistant {
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 0.8rem;
  align-items: flex-start;
}

.scene1-chat-avatar {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.4rem;
  height: 2.4rem;
  border-radius: 0.85rem;
  background: linear-gradient(135deg, #2b6a4a 0%, #1d3e30 100%);
  color: #eef8f2;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.76rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

.scene1-chat-bubble {
  border-radius: 1.4rem;
  padding: 1rem 1.05rem;
}

.scene1-chat-bubble--user {
  max-width: min(100%, 32rem);
  border-top-right-radius: 0.45rem;
  background: linear-gradient(135deg, #ece7db 0%, #d8d2c3 100%);
  color: #1c1a17;
  box-shadow: 0 8px 24px rgba(0, 0, 0, 0.16);
}

.scene1-chat-bubble--assistant {
  border-top-left-radius: 0.45rem;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

.scene1-chat-bubble__label {
  margin: 0 0 0.45rem;
  color: inherit;
  opacity: 0.62;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.73rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.scene1-chat-bubble__prompt {
  margin: 0;
  max-width: none;
  font-size: 0.98rem;
  line-height: 1.75;
}

.scene1-chat-response p {
  max-width: none;
  margin: 0 0 1rem;
  color: #edf1ef;
  font-size: 0.97rem;
  line-height: 1.9;
}

.scene1-chat-response strong {
  color: #ffffff;
}

.scene1-chat-response .scene1-chat-signoff {
  margin-bottom: 0;
  color: #a9d6bf;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.8rem;
}

@media (max-width: 720px) {
  .scene1-chat-modal {
    padding: 0.75rem;
  }

  .scene1-chat-modal__header {
    flex-direction: column;
    align-items: stretch;
  }

  .scene1-chat-modal__meta {
    justify-content: space-between;
  }

  .scene1-chat-thread {
    padding: 0.9rem;
  }

  .scene1-chat-message--assistant {
    grid-template-columns: 1fr;
  }

  .scene1-chat-avatar {
    width: 2.2rem;
    height: 2.2rem;
  }

  .scene1-chat-bubble--user {
    max-width: 100%;
  }
}

/* ==========================================================================
   CoLA Quiz Modal
   ========================================================================== */

.cola-modal-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 1rem;
  background: rgba(23, 21, 18, 0.55);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
}

.cola-modal-overlay[hidden] {
  display: none;
}

.cola-modal {
  position: relative;
  width: min(520px, 100%);
  max-height: calc(100vh - 2rem);
  overflow-y: auto;
  padding: 2rem 1.8rem 1.4rem;
  border-radius: var(--radius-lg);
  background: var(--paper);
  box-shadow: 0 24px 64px rgba(54, 43, 26, 0.22);
}

.cola-modal-close {
  position: absolute;
  top: 0.8rem;
  right: 0.9rem;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2.2rem;
  height: 2.2rem;
  border: none;
  border-radius: 50%;
  background: transparent;
  color: var(--muted);
  font-size: 1.5rem;
  cursor: pointer;
  transition: background 120ms ease;
}

.cola-modal-close:hover {
  background: rgba(23, 21, 18, 0.08);
}

.cola-modal-header h4 {
  margin: 0 0 0.3rem;
  font-family: "Cormorant Garamond", Georgia, serif;
  font-size: 1.55rem;
  font-weight: 500;
  color: var(--ink);
}

.cola-modal-sub {
  margin: 0 0 1.2rem;
  font-size: 0.9rem;
  color: var(--muted);
}

.cola-progress {
  margin: 0 0 0.6rem;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.76rem;
  letter-spacing: 0.06em;
  color: var(--muted-soft);
}

.cola-sentence {
  margin: 0 0 1.2rem;
  padding: 1rem 1.2rem;
  border-left: 3px solid var(--accent);
  background: rgba(43, 106, 74, 0.05);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
  font-size: 1.15rem;
  font-style: italic;
  line-height: 1.7;
  color: var(--ink);
}

.cola-actions {
  display: flex;
  gap: 0.7rem;
  margin-bottom: 1rem;
}

.cola-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.6rem 1.2rem;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.7);
  color: var(--ink);
  font: inherit;
  font-size: 0.92rem;
  cursor: pointer;
  transition: background 120ms ease, border-color 120ms ease, opacity 120ms ease;
}

.cola-btn:hover:not(:disabled) {
  background: rgba(255, 255, 255, 0.95);
  border-color: var(--accent);
}

.cola-btn:disabled {
  opacity: 0.55;
  cursor: default;
}

.cola-btn-correct-answer {
  border-color: #2b6a4a !important;
  background: rgba(43, 106, 74, 0.12) !important;
  opacity: 1 !important;
}

.cola-btn-wrong-answer.cola-btn-selected {
  border-color: #b45309 !important;
  background: rgba(245, 158, 11, 0.12) !important;
  opacity: 1 !important;
}

.cola-feedback {
  margin: 0 0 1rem;
  padding: 1rem 1.1rem;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  line-height: 1.75;
  color: var(--ink);
}

.cola-feedback strong {
  display: block;
  margin-bottom: 0.25rem;
  font-size: 1rem;
}

.cola-feedback p {
  margin: 0.5rem 0 0;
  font-size: 0.88rem;
  color: var(--muted);
  max-width: none;
}

.cola-feedback-correct {
  background: rgba(43, 106, 74, 0.08);
  border: 1px solid rgba(43, 106, 74, 0.2);
}

.cola-feedback-wrong {
  background: rgba(245, 158, 11, 0.08);
  border: 1px solid rgba(245, 158, 11, 0.2);
}

.cola-btn-next,
.cola-btn-retry {
  margin-top: 0.5rem;
  background: rgba(43, 106, 74, 0.1);
  border-color: var(--accent);
  color: var(--accent);
  font-weight: 600;
}

.cola-btn-next:hover:not(:disabled),
.cola-btn-retry:hover:not(:disabled) {
  background: rgba(43, 106, 74, 0.2);
}

.cola-modal-result {
  text-align: center;
  padding: 2rem 0 1rem;
}

.cola-result-text {
  margin: 0 0 1.4rem;
  font-size: 1.08rem;
  line-height: 1.8;
  color: var(--ink);
}

.cola-result-text span {
  display: block;
  margin-top: 0.6rem;
  font-size: 0.88rem;
  color: var(--muted);
}

.cola-license {
  margin: 1.2rem 0 0;
  padding-top: 0.8rem;
  border-top: 1px solid var(--line);
  font-size: 0.74rem;
  color: var(--muted-soft);
}

.cola-license a {
  color: var(--muted);
}

@media (max-width: 640px) {
  .cola-modal {
    padding: 1.5rem 1.1rem 1.1rem;
  }

  .cola-sentence {
    font-size: 1.02rem;
  }

  .cola-actions {
    flex-direction: column;
  }
}

.demo-placeholder {
  margin-top: 0.9rem;
}

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

.llm-demo {
  margin-top: 1.15rem;
}

.llm-demo-warning {
  margin-bottom: 1rem;
  padding: 1rem 1.05rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-md);
  background: rgba(187, 166, 125, 0.11);
}

.llm-demo-warning p {
  max-width: none;
  font-size: 0.92rem;
  color: var(--ink);
}

.llm-demo-consent {
  display: flex;
  align-items: flex-start;
  gap: 0.7rem;
  margin-top: 0.85rem;
  font-size: 0.92rem;
  line-height: 1.65;
  color: var(--ink);
}

.llm-demo-consent input {
  margin-top: 0.2rem;
  accent-color: var(--accent);
}

.llm-demo-controls {
  margin-bottom: 1rem;
}

.llm-demo-label {
  display: block;
  margin-bottom: 0.45rem;
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
}

.llm-demo-prompt {
  width: 100%;
  min-height: 7.5rem;
  padding: 0.9rem 1rem;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.68);
  color: var(--ink);
  font: inherit;
  font-size: 0.98rem;
  line-height: 1.7;
  resize: vertical;
}

.llm-demo-prompt:focus {
  outline: 2px solid rgba(43, 106, 74, 0.18);
  outline-offset: 2px;
}

.llm-demo-actions {
  display: flex;
  justify-content: flex-end;
  margin: 0 0 1rem;
}

.llm-demo-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
}

.llm-demo-model {
  display: flex;
  flex-direction: column;
  gap: 0.8rem;
  padding: 1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.66), rgba(255, 252, 246, 0.46));
  min-width: 0;
}

.llm-demo-model-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 0.8rem;
}

.llm-demo-model h4 {
  margin: 0.08rem 0 0;
  font-size: 1rem;
  min-width: 0;
  overflow-wrap: break-word;
}

.llm-demo-kicker {
  margin: 0;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

.llm-demo-chip {
  display: inline-flex;
  align-items: center;
  padding: 0.28rem 0.62rem;
  border-radius: 999px;
  background: rgba(43, 106, 74, 0.08);
  color: var(--accent);
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  white-space: nowrap;
  flex-shrink: 0;
}

.llm-demo-model-copy {
  margin: 0;
  max-width: none;
  font-size: 0.9rem;
  color: var(--muted);
  flex: 1;
}

.llm-demo-model-copy a {
  word-break: break-all;
}

.llm-demo-model .inline-demo-button {
  margin: 0;
  align-self: flex-start;
}

.llm-demo-status {
  margin: 0;
  max-width: none;
  min-height: 1.8em;
  font-size: 0.86rem;
  color: var(--muted);
}

.llm-demo-progress {
  position: relative;
  width: 100%;
  height: 0.45rem;
  overflow: hidden;
  border-radius: 999px;
  background: rgba(23, 21, 18, 0.08);
}

.llm-demo-progress-bar {
  display: block;
  width: 0%;
  height: 100%;
  border-radius: inherit;
  background: linear-gradient(90deg, #c6b082 0%, #2b6a4a 100%);
  transition: width 160ms ease;
}

.llm-demo-output {
  margin: 0;
  min-height: 14rem;
  padding: 1rem;
  overflow: auto;
  border-radius: var(--radius-md);
  background: #1b1a18;
  color: #f4efe4;
  font-family: "IBM Plex Mono", ui-monospace, monospace;
  font-size: 0.84rem;
  line-height: 1.72;
  white-space: pre-wrap;
  word-break: break-word;
}

/* --- Key term first appearance --- */
.term {
  font-weight: 600;
  color: var(--accent-2);
}

/* --- Section epigraph --- */
.epigraph {
  margin: 0 0 2rem;
  padding: 1rem 1.2rem;
  font-size: 1.05rem;
  line-height: 1.75;
  color: var(--ink);
  border-left: 3px solid var(--accent);
  background: rgba(43, 106, 74, 0.04);
  border-radius: 0 var(--radius-md) var(--radius-md) 0;
}

/* --- History section h4 --- */
.history-section h4 {
  margin-top: 2rem;
  margin-bottom: 0.6rem;
  font-family: "Manrope", system-ui, sans-serif;
  font-size: 1.05rem;
  font-weight: 600;
  color: var(--accent-2);
}