:root {
  color-scheme: light;
  --bg: #f4f4f6;
  --bg-deep: #ececf1;
  --panel: rgba(255, 255, 255, 0.68);
  --panel-strong: rgba(255, 255, 255, 0.88);
  --panel-dark: rgba(16, 18, 24, 0.82);
  --surface-line: rgba(18, 20, 28, 0.08);
  --surface-line-strong: rgba(18, 20, 28, 0.14);
  --text: #101114;
  --muted: rgba(20, 24, 32, 0.66);
  --muted-strong: rgba(20, 24, 32, 0.82);
  --accent: #0071e3;
  --accent-soft: rgba(0, 113, 227, 0.14);
  --accent-deep: #1859d1;
  --shadow: 0 28px 70px rgba(16, 18, 24, 0.08);
  --backdrop-a: rgba(97, 178, 255, 0.22);
  --backdrop-b: rgba(255, 173, 97, 0.16);
  --button-text: #ffffff;
  --timeline-gradient: linear-gradient(
    180deg,
    rgba(0, 113, 227, 0.3),
    rgba(0, 113, 227, 0.08)
  );
}

[data-theme="dark"] {
  color-scheme: dark;
  --bg: #06070a;
  --bg-deep: #0b0d11;
  --panel: rgba(20, 22, 28, 0.62);
  --panel-strong: rgba(18, 20, 25, 0.84);
  --panel-dark: rgba(10, 12, 18, 0.84);
  --surface-line: rgba(255, 255, 255, 0.08);
  --surface-line-strong: rgba(255, 255, 255, 0.14);
  --text: #f4f5f7;
  --muted: rgba(242, 244, 248, 0.64);
  --muted-strong: rgba(242, 244, 248, 0.82);
  --accent: #4da3ff;
  --accent-soft: rgba(77, 163, 255, 0.18);
  --accent-deep: #88c4ff;
  --shadow: 0 28px 80px rgba(0, 0, 0, 0.36);
  --backdrop-a: rgba(77, 163, 255, 0.2);
  --backdrop-b: rgba(255, 163, 83, 0.12);
  --button-text: #04101c;
  --timeline-gradient: linear-gradient(
    180deg,
    rgba(77, 163, 255, 0.34),
    rgba(77, 163, 255, 0.08)
  );
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Noto Sans SC", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 12% 10%, var(--backdrop-a), transparent 24%),
    radial-gradient(circle at 88% 16%, var(--backdrop-b), transparent 20%),
    linear-gradient(180deg, var(--bg), var(--bg-deep));
  transition: background 240ms ease, color 240ms ease;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  background:
    linear-gradient(rgba(255, 255, 255, 0.05) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.05) 1px, transparent 1px);
  background-size: 120px 120px;
  opacity: 0.12;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.38), transparent 82%);
  pointer-events: none;
}

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

button {
  font: inherit;
}

.backdrop {
  position: fixed;
  z-index: 0;
  border-radius: 50%;
  filter: blur(90px);
  pointer-events: none;
}

.backdrop-orb-a {
  top: 10%;
  left: 5%;
  width: 24rem;
  height: 24rem;
  background: var(--backdrop-a);
}

.backdrop-orb-b {
  right: 4%;
  bottom: 10%;
  width: 22rem;
  height: 22rem;
  background: var(--backdrop-b);
}

.noise-mask {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at top center, rgba(255, 255, 255, 0.06), transparent 36%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.04), transparent 38%);
}

.page-shell {
  position: relative;
  z-index: 1;
  width: min(1320px, calc(100% - 32px));
  margin: 0 auto;
  padding: 20px 0 56px;
}

.section {
  margin-top: 88px;
}

.glass,
.glass-panel {
  border: 1px solid var(--surface-line);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.08), transparent),
    var(--panel);
  box-shadow: var(--shadow);
  backdrop-filter: blur(28px);
  -webkit-backdrop-filter: blur(28px);
}

.glass-panel {
  border-radius: 36px;
}

.site-header {
  position: sticky;
  top: 14px;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
  padding: 14px 18px;
  border-radius: 26px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  min-width: 0;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 44px;
  height: 44px;
  border-radius: 15px;
  background: linear-gradient(135deg, var(--accent), var(--accent-deep));
  color: var(--button-text);
  font-family: "Manrope", sans-serif;
  font-size: 1.18rem;
  font-weight: 800;
}

.brand-copy {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.brand-copy strong,
.site-nav a,
.hero-stage h1,
.hero-panel h2,
.section-heading h2,
.chapter-card h3,
.spotlight-card h3,
.timeline-card h3,
.signal-card h3,
.finale-copy h2 {
  font-family: "Manrope", "Noto Sans SC", sans-serif;
}

.brand-copy strong {
  font-size: 1rem;
}

.brand-copy small,
.site-nav,
.hero-copy,
.section-heading p,
.timeline-card p,
.timeline-impact,
.signal-card p,
.signal-card li,
.chapter-card p,
.chapter-card li,
.footer-meta,
.hero-panel p {
  color: var(--muted);
}

.site-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
}

.site-nav a {
  position: relative;
  font-size: 0.94rem;
}

.site-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -6px;
  height: 2px;
  background: linear-gradient(90deg, var(--accent), transparent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}

.site-nav a:hover::after,
.site-nav a:focus-visible::after {
  transform: scaleX(1);
}

.header-actions,
.hero-actions {
  display: flex;
  align-items: center;
  gap: 12px;
}

.theme-toggle,
.primary-button,
.secondary-button,
.phase-filter {
  border: 1px solid var(--surface-line);
  transition:
    transform 180ms ease,
    border-color 180ms ease,
    background 180ms ease,
    box-shadow 180ms ease,
    color 180ms ease;
}

.theme-toggle,
.primary-button,
.secondary-button,
.phase-filter {
  cursor: pointer;
}

.theme-toggle:hover,
.primary-button:hover,
.secondary-button:hover,
.phase-filter:hover {
  transform: translateY(-1px);
}

.theme-toggle {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-height: 46px;
  padding: 0 16px;
  border-radius: 999px;
  color: var(--muted-strong);
  background: rgba(255, 255, 255, 0.05);
}

.theme-toggle__icon {
  display: inline-grid;
  place-items: center;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.12);
}

.primary-button,
.secondary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 54px;
  padding: 0 26px;
  border-radius: 999px;
  font-weight: 700;
}

.primary-button {
  color: var(--button-text);
  background: linear-gradient(135deg, var(--accent), var(--accent-deep));
  box-shadow: 0 20px 40px rgba(0, 113, 227, 0.16);
}

.secondary-button {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
}

.hero {
  display: grid;
  gap: 24px;
}

.hero-stage {
  padding: 56px 8px 0;
  text-align: center;
}

.eyebrow,
.panel-kicker,
.timeline-pill,
.timeline-phase,
.signal-kicker {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--accent);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.eyebrow::before,
.panel-kicker::before,
.signal-kicker::before {
  content: "";
  width: 28px;
  height: 1px;
  background: currentColor;
  opacity: 0.55;
}

.hero-stage h1 {
  width: min(980px, 100%);
  margin: 18px auto 18px;
  font-size: clamp(3rem, 7vw, 6rem);
  line-height: 0.98;
  letter-spacing: -0.06em;
}

.hero-copy {
  width: min(760px, 100%);
  margin: 0 auto;
  font-size: 1.12rem;
  line-height: 1.9;
}

.hero-actions {
  justify-content: center;
  margin-top: 28px;
}

.hero-panels {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 18px;
}

.hero-panel {
  padding: 28px;
}

.hero-panel h2 {
  margin: 14px 0 6px;
  font-size: clamp(2rem, 4vw, 3.2rem);
}

.hero-panel--dark {
  color: #f7f8fa;
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.04), transparent),
    var(--panel-dark);
  border-color: rgba(255, 255, 255, 0.08);
}

.hero-panel--dark .panel-kicker,
.hero-panel--dark .panel-quote {
  color: rgba(244, 246, 250, 0.88);
}

.panel-quote {
  margin: 14px 0 0;
  font-size: 1.45rem;
  line-height: 1.5;
}

.stat-strip {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 18px;
}

.stat-strip span {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 0 14px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--muted-strong);
  font-size: 0.9rem;
}

.section-heading {
  max-width: 880px;
}

.section-heading--center {
  margin: 0 auto 22px;
  text-align: center;
}

.section-heading h2 {
  margin: 16px 0 12px;
  font-size: clamp(2.2rem, 4vw, 4rem);
  line-height: 1.06;
  letter-spacing: -0.05em;
}

.metric-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 18px;
}

.metric-card,
.chapter-card,
.spotlight-card,
.timeline-card,
.signal-card {
  border-radius: 32px;
  border: 1px solid var(--surface-line);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.08), transparent),
    var(--panel-strong);
  box-shadow: var(--shadow);
}

.metric-card {
  padding: 26px 24px;
}

.metric-card strong {
  display: block;
  font-family: "Manrope", sans-serif;
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1;
}

.metric-card span {
  display: block;
  margin-top: 10px;
  color: var(--muted);
}

.chapter-band {
  padding: 36px 0 0;
}

.chapter-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 18px;
}

.chapter-card {
  padding: 26px;
}

.chapter-card h3,
.spotlight-card h3,
.timeline-card h3,
.signal-card h3 {
  margin: 16px 0 10px;
  font-size: 1.3rem;
  line-height: 1.25;
}

.chapter-card p,
.spotlight-card p,
.timeline-card p,
.signal-card p {
  line-height: 1.75;
}

.chapter-card ul,
.signal-card ul {
  margin: 16px 0 0;
  padding-left: 18px;
}

.chapter-card li + li,
.signal-card li + li {
  margin-top: 8px;
}

.spotlight {
  display: grid;
  grid-template-columns: 0.78fr 1.22fr;
  gap: 20px;
  align-items: start;
}

.spotlight-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.spotlight-card {
  padding: 24px;
}

.spotlight-card .timeline-version-label {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 0 12px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--muted-strong);
  font-family: "Manrope", sans-serif;
  font-size: 0.9rem;
  font-weight: 800;
}

.timeline-toolbar {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
  padding: 18px 20px;
  border-radius: 24px;
}

.filter-intro strong {
  display: block;
  font-family: "Manrope", sans-serif;
  font-size: 1rem;
}

.filter-intro span {
  color: var(--muted);
}

.phase-filters {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 10px;
}

.phase-filter {
  min-height: 42px;
  padding: 0 16px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
}

.phase-filter.is-active {
  color: var(--button-text);
  background: linear-gradient(135deg, var(--accent), var(--accent-deep));
  box-shadow: 0 16px 32px rgba(0, 113, 227, 0.16);
}

.timeline-stream {
  position: relative;
  display: grid;
  gap: 20px;
  margin-top: 26px;
  padding-left: 78px;
}

.timeline-stream::before {
  content: "";
  position: absolute;
  left: 28px;
  top: 10px;
  bottom: 10px;
  width: 2px;
  border-radius: 999px;
  background: var(--timeline-gradient);
}

.timeline-entry {
  position: relative;
}

.timeline-entry::before {
  content: "";
  position: absolute;
  left: -58px;
  top: 34px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent), var(--accent-deep));
  box-shadow:
    0 0 0 8px rgba(0, 113, 227, 0.08),
    0 14px 28px rgba(0, 113, 227, 0.14);
}

.timeline-card {
  padding: 28px 30px;
}

.timeline-card-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
}

.timeline-phase {
  color: var(--muted-strong);
}

.timeline-version-block {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.timeline-version-pill {
  display: inline-flex;
  align-items: center;
  min-height: 34px;
  padding: 0 12px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--muted-strong);
  font-family: "Manrope", sans-serif;
  font-size: 0.92rem;
  font-weight: 800;
}

.timeline-impact {
  margin-top: 18px;
  padding: 16px 18px;
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--surface-line);
  line-height: 1.75;
}

.timeline-impact strong {
  display: block;
  margin-bottom: 6px;
  color: var(--muted-strong);
  font-size: 0.95rem;
}

.timeline-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 18px;
}

.timeline-tag {
  display: inline-flex;
  align-items: center;
  min-height: 30px;
  padding: 0 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid var(--surface-line);
  color: var(--muted);
  font-size: 0.84rem;
}

.signal-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.signal-card {
  padding: 26px;
}

.signal-card .thread-accent {
  display: inline-flex;
  align-items: center;
  min-height: 32px;
  padding: 0 12px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--muted-strong);
  font-size: 0.84rem;
  font-weight: 600;
}

.finale-panel {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 22px;
  padding: 34px 36px;
}

.finale-copy h2 {
  margin: 16px 0 0;
  font-size: clamp(2rem, 3vw, 3.2rem);
  line-height: 1.08;
  letter-spacing: -0.05em;
}

.finale-panel p {
  margin: 0;
  color: var(--muted);
  line-height: 1.9;
  font-size: 1.04rem;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  margin-top: 64px;
  padding: 18px 22px;
  border-radius: 24px;
}

.site-footer strong {
  display: block;
  font-family: "Manrope", sans-serif;
}

.site-footer span {
  color: var(--muted);
}

.footer-meta {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 8px 14px;
  font-size: 0.92rem;
}

.reveal {
  opacity: 0;
  transform: translateY(26px);
  transition:
    opacity 520ms ease,
    transform 520ms ease;
}

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

@media (max-width: 1180px) {
  .hero-panels,
  .spotlight,
  .spotlight-grid,
  .finale-panel,
  .metric-grid,
  .chapter-grid,
  .signal-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 920px) {
  .site-header,
  .timeline-toolbar,
  .site-footer {
    flex-direction: column;
    align-items: stretch;
  }

  .site-nav,
  .phase-filters,
  .footer-meta {
    justify-content: flex-start;
  }
}

@media (max-width: 720px) {
  .page-shell {
    width: min(100% - 20px, 1320px);
    padding-top: 12px;
  }

  .section {
    margin-top: 64px;
  }

  .hero-stage {
    padding-top: 40px;
  }

  .hero-stage h1,
  .section-heading h2,
  .finale-copy h2 {
    letter-spacing: -0.04em;
  }

  .timeline-stream {
    padding-left: 48px;
  }

  .timeline-stream::before {
    left: 14px;
  }

  .timeline-entry::before {
    left: -34px;
  }

  .hero-panel,
  .metric-card,
  .chapter-card,
  .spotlight-card,
  .timeline-card,
  .signal-card,
  .finale-panel {
    border-radius: 28px;
  }

  .hero-panel,
  .metric-card,
  .chapter-card,
  .spotlight-card,
  .timeline-card,
  .signal-card {
    padding: 24px;
  }

  .finale-panel {
    padding: 28px;
  }
}

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

  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }

  .reveal {
    opacity: 1;
    transform: none;
  }
}