:root {
  --shell-width: 1320px;
  --shell-gutter: 24px;
  --grid-gap: 24px;
  --bg: #121212;
  --bg-soft: #181818;
  --panel: #1d1b1a;
  --panel-2: #23211f;
  --paper: #f2ece4;
  --paper-soft: #e5ddd1;
  --ink: #151515;
  --text: #f3efe8;
  --muted: rgba(243, 239, 232, 0.68);
  --line: rgba(255, 255, 255, 0.11);
  --line-strong: rgba(255, 255, 255, 0.22);
  --accent: #7f2f2f;
  --accent-soft: rgba(127, 47, 47, 0.12);
  --shadow: 0 26px 80px rgba(0, 0, 0, 0.26);
}

body.light-mode {
  --bg: #eee7dd;
  --bg-soft: #e6ddd1;
  --panel: #f7f1e8;
  --panel-2: #f1eadf;
  --paper: #fffdfa;
  --paper-soft: #f3ebdf;
  --ink: #171717;
  --text: #171717;
  --muted: rgba(23, 23, 23, 0.7);
  --line: rgba(23, 23, 23, 0.11);
  --line-strong: rgba(23, 23, 23, 0.2);
  --accent: #8d3d38;
  --accent-soft: rgba(141, 61, 56, 0.12);
  --shadow: 0 18px 50px rgba(29, 22, 18, 0.08);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  background:
    radial-gradient(circle at top, rgba(255, 255, 255, 0.04), transparent 30%),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-soft) 100%);
  color: var(--text);
  font-family: 'Inter', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
  transition: background 260ms ease, color 260ms ease;
}

button,
a,
input {
  color: inherit;
  font: inherit;
}

.page-shell {
  position: relative;
  width: min(var(--shell-width), calc(100% - (var(--shell-gutter) * 2)));
  margin: 0 auto;
  padding-bottom: 40px;
}

.page-shell > * {
  position: relative;
  z-index: 1;
}

.page-grid {
  position: absolute;
  inset: 0;
  z-index: 0;
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: var(--grid-gap);
  pointer-events: none;
}

.page-grid span {
  border-left: 1px solid var(--line);
  opacity: 0.65;
}

.page-grid span:last-child {
  border-right: 1px solid var(--line);
}

.topbar {
  position: sticky;
  top: 0;
  display: grid;
  grid-template-columns: 1fr auto auto;
  align-items: center;
  gap: 18px;
  padding: 18px 0;
  margin-bottom: 8px;
  background: linear-gradient(180deg, color-mix(in srgb, var(--bg) 88%, transparent 12%), color-mix(in srgb, var(--bg) 58%, transparent 42%));
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--line);
  z-index: 10;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  font-size: 0.95rem;
  font-weight: 700;
}

.brand-mark {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 0 6px var(--accent-soft);
}

.nav-links {
  display: flex;
  gap: 22px;
}

.nav-links a,
.mode-toggle,
.footer {
  text-decoration: none;
  font-size: 0.9rem;
  color: var(--muted);
}

.nav-links a:hover,
.mode-toggle:hover {
  color: var(--text);
}

.mode-toggle {
  padding: 10px 14px;
  border: 1px solid var(--line);
  background: transparent;
  cursor: pointer;
  transition: border-color 180ms ease, background 180ms ease, color 180ms ease;
}

.mode-toggle:hover {
  border-color: var(--line-strong);
  background: var(--accent-soft);
}

main {
  display: block;
}

.section,
.hero,
.footer {
  padding: 36px 0 0;
}

.ruled-row {
  border-top: 1px solid var(--line);
}

.hero-meta,
.section-head,
.footer,
.closing-signoff,
.preview-topline,
.preview-foot,
.density-legend {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: baseline;
}

.kicker,
.issue,
.stage-kicker,
.control-label,
.preview-kicker,
.ledger-item span,
.system-card span,
.closing-signoff span,
.mini-module summary,
.preview-topline span {
  margin: 0;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  font-size: 0.72rem;
  color: var(--muted);
}

.hero-meta,
.section-head {
  padding-top: 14px;
}

.hero-grid,
.statement-grid,
.works-layout,
.system-grid,
.hero-ledger,
.components-layout {
  display: grid;
  gap: var(--grid-gap);
  padding-top: 24px;
}

.hero-grid {
  grid-template-columns: repeat(12, minmax(0, 1fr));
}

.hero-copy {
  grid-column: 1 / span 8;
}

.hero-note {
  grid-column: 10 / span 3;
  align-self: end;
}

.hero-copy h1,
.section-head h2,
.work-stage h3,
.preview-card h3,
.closing-panel h2 {
  font-family: 'Noto Serif SC', 'Songti SC', serif;
  letter-spacing: -0.03em;
  font-weight: 700;
}

.hero-copy h1 {
  margin: 0;
  font-size: clamp(3.3rem, 7.8vw, 6.6rem);
  line-height: 1.04;
  max-width: 11ch;
}

.hero-text,
.statement-grid p,
.section-caption,
.work-item small,
.work-stage p,
.system-card p,
.preview-card p,
.mini-module p,
.closing-panel p,
.hero-note p {
  color: var(--muted);
  line-height: 1.82;
}

.hero-text {
  margin: 28px 0 0;
  max-width: 48rem;
  font-size: 1.05rem;
}

.framed-note,
.ledger-item,
.work-item,
.stage-card,
.system-card,
.control-panel,
.preview-card,
.mini-module,
.closing-panel {
  border: 1px solid var(--line);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.025), rgba(255, 255, 255, 0.01));
  box-shadow: var(--shadow);
}

.framed-note {
  padding: 18px 20px;
}

.hero-ledger {
  grid-template-columns: repeat(12, minmax(0, 1fr));
}

.ledger-item {
  padding: 18px 20px 20px;
}

.ledger-item:nth-child(1) {
  grid-column: 1 / span 4;
}

.ledger-item:nth-child(2) {
  grid-column: 5 / span 4;
}

.ledger-item:nth-child(3) {
  grid-column: 9 / span 4;
}

.ledger-item strong {
  display: block;
  margin-top: 12px;
  line-height: 1.65;
  font-size: 1rem;
}

.section-head h2,
.closing-panel h2 {
  margin: 10px 0 0;
  font-size: clamp(2rem, 4vw, 3.5rem);
  line-height: 1.12;
}

.statement-grid {
  grid-template-columns: repeat(12, minmax(0, 1fr));
}

.statement-grid p:nth-child(1) {
  grid-column: 1 / span 6;
}

.statement-grid p:nth-child(2) {
  grid-column: 7 / span 6;
}

.works-layout {
  grid-template-columns: repeat(12, minmax(0, 1fr));
}

.work-list {
  grid-column: 1 / span 5;
  display: grid;
  gap: 12px;
}

.work-stage {
  grid-column: 6 / span 7;
}

.work-item {
  width: 100%;
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 16px;
  padding: 18px 18px 20px;
  text-align: left;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.02), transparent);
  cursor: pointer;
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

.work-item:hover,
.work-item.is-active {
  transform: translateX(4px);
  border-color: var(--line-strong);
  background: linear-gradient(180deg, var(--accent-soft), rgba(255, 255, 255, 0.02));
}

.work-number {
  letter-spacing: 0.14em;
  font-size: 0.8rem;
  color: var(--muted);
}

.work-item.is-active .work-number,
.work-item.is-active small {
  color: var(--text);
}

.work-item strong {
  display: block;
  margin-bottom: 6px;
  font-size: 1.08rem;
}

.stage-card {
  position: relative;
  overflow: hidden;
  min-height: 100%;
  padding: 34px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.04), transparent 36%),
    linear-gradient(180deg, var(--panel), color-mix(in srgb, var(--panel) 84%, black 16%));
}

.stage-card::before {
  content: '';
  position: absolute;
  inset: 0;
  pointer-events: none;
  background: linear-gradient(180deg, transparent, rgba(255, 255, 255, 0.045));
}

.stage-card.is-refreshing {
  animation: stageRefresh 320ms ease;
}

.stage-index {
  margin: 18px 0 12px;
  font-size: clamp(4rem, 8vw, 7.6rem);
  line-height: 0.92;
  color: color-mix(in srgb, var(--accent) 74%, var(--text) 26%);
}

.work-stage h3,
.preview-card h3 {
  font-size: clamp(1.8rem, 3vw, 2.8rem);
  margin: 0 0 14px;
}

.system-grid {
  grid-template-columns: repeat(12, minmax(0, 1fr));
}

.system-card {
  padding: 22px;
}

.system-card:nth-child(1) {
  grid-column: 1 / span 4;
}

.system-card:nth-child(2) {
  grid-column: 5 / span 4;
}

.system-card:nth-child(3) {
  grid-column: 9 / span 4;
}

.system-card strong {
  display: block;
  margin: 16px 0 10px;
  font-size: 1.16rem;
  line-height: 1.4;
}

.components-layout {
  grid-template-columns: repeat(12, minmax(0, 1fr));
}

.control-panel {
  grid-column: 1 / span 5;
  padding: 20px;
  display: grid;
  gap: 22px;
}

.preview-panel {
  grid-column: 6 / span 7;
  display: grid;
  gap: 18px;
}

.control-block {
  display: grid;
  gap: 12px;
}

.segmented,
.swatch-row,
.note-stack {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

.tone-chip,
.note-item {
  padding: 10px 14px;
  border: 1px solid var(--line);
  background: transparent;
  cursor: pointer;
  transition: border-color 180ms ease, background 180ms ease, color 180ms ease;
}

.tone-chip.is-active,
.note-item.is-active,
.tone-chip:hover,
.note-item:hover {
  border-color: var(--line-strong);
  background: var(--accent-soft);
}

.density-range {
  width: 100%;
  accent-color: var(--accent);
}

.density-legend {
  font-size: 0.84rem;
  color: var(--muted);
}

.swatch {
  width: 34px;
  height: 34px;
  border-radius: 50%;
  border: 1px solid var(--line);
  background: var(--swatch);
  cursor: pointer;
  box-shadow: inset 0 0 0 4px rgba(255, 255, 255, 0.08);
}

.swatch.is-active {
  outline: 2px solid color-mix(in srgb, var(--swatch) 60%, white 40%);
  outline-offset: 2px;
}

.preview-card {
  padding: 24px;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.03), transparent 34%),
    linear-gradient(180deg, var(--panel-2), color-mix(in srgb, var(--panel-2) 86%, black 14%));
  transition: border-color 180ms ease, transform 180ms ease, background 180ms ease;
}

.preview-card[data-tone='quiet'] {
  transform: translateX(-2px);
}

.preview-card[data-tone='balanced'] {
  transform: translateX(0);
}

.preview-card[data-tone='dramatic'] {
  transform: translateX(2px);
}

.preview-body {
  padding: 22px 0 28px;
}

.preview-foot {
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

#previewNote {
  max-width: 32ch;
  line-height: 1.6;
}

.mini-modules {
  display: grid;
  gap: 12px;
}

.mini-module {
  padding: 16px 18px;
}

.mini-module summary {
  cursor: pointer;
}

.mini-module p {
  margin: 12px 0 0;
}

.closing-panel {
  padding: 34px;
  background:
    linear-gradient(0deg, color-mix(in srgb, var(--accent) 12%, transparent 88%), color-mix(in srgb, var(--accent) 12%, transparent 88%)),
    linear-gradient(180deg, var(--paper-soft), var(--paper));
  color: var(--ink);
  border-color: rgba(0, 0, 0, 0.08);
}

.closing-panel .kicker,
.closing-panel p,
.closing-signoff span {
  color: rgba(20, 20, 20, 0.72);
}

.closing-signoff {
  margin-top: 28px;
  padding-top: 18px;
  border-top: 1px solid rgba(20, 20, 20, 0.12);
}

.footer {
  margin-top: 28px;
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 650ms ease, transform 650ms ease;
}

.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

@keyframes stageRefresh {
  0% {
    transform: translateY(8px);
    opacity: 0.88;
  }
  100% {
    transform: translateY(0);
    opacity: 1;
  }
}

@media (max-width: 1100px) {
  .topbar {
    grid-template-columns: 1fr;
    justify-items: start;
  }

  .hero-copy,
  .hero-note,
  .ledger-item,
  .statement-grid p:nth-child(1),
  .statement-grid p:nth-child(2),
  .work-list,
  .work-stage,
  .system-card,
  .control-panel,
  .preview-panel {
    grid-column: 1 / -1;
  }

  .hero-grid,
  .hero-ledger,
  .statement-grid,
  .works-layout,
  .system-grid,
  .components-layout {
    grid-template-columns: 1fr;
  }

  .hero-copy h1 {
    max-width: none;
  }

  .hero-note {
    order: 2;
  }
}

@media (max-width: 720px) {
  :root {
    --shell-gutter: 12px;
    --grid-gap: 16px;
  }

  .page-grid {
    display: none;
  }

  .nav-links {
    display: none;
  }

  .hero-copy h1 {
    font-size: clamp(2.5rem, 13vw, 4.2rem);
  }

  .section,
  .hero,
  .footer {
    padding-top: 28px;
  }

  .stage-card,
  .closing-panel,
  .preview-card,
  .control-panel,
  .system-card,
  .ledger-item,
  .framed-note,
  .mini-module {
    padding: 20px;
  }

  .work-item {
    grid-template-columns: 40px 1fr;
    padding: 16px;
  }

  .preview-topline,
  .preview-foot,
  .closing-signoff,
  .density-legend,
  .footer {
    flex-direction: column;
    align-items: flex-start;
  }
}