:root {
  color-scheme: dark;
  --bg: #0e1212;
  --panel: #151b1b;
  --panel-2: #1d2524;
  --ink: #f4efe2;
  --muted: #bfb7a3;
  --soft: #918a7b;
  --line: rgba(244, 239, 226, 0.14);
  --gold: #e8b75d;
  --ember: #e0522e;
  --jade: #72b795;
  --rail: 248px;
  --radius: 6px;
  --shadow: 0 28px 70px rgba(0, 0, 0, 0.34);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background:
    linear-gradient(90deg, rgba(232, 183, 93, 0.06) 1px, transparent 1px),
    linear-gradient(180deg, rgba(232, 183, 93, 0.04) 1px, transparent 1px),
    radial-gradient(circle at 80% 10%, rgba(224, 82, 46, 0.18), transparent 26rem),
    var(--bg);
  background-size: 42px 42px, 42px 42px, auto, auto;
  color: var(--ink);
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", Arial, sans-serif;
  font-size: 15px;
  line-height: 1.68;
  text-rendering: optimizeLegibility;
}

body.nav-open {
  overflow: hidden;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

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

button,
a,
summary {
  -webkit-tap-highlight-color: transparent;
}

p,
h1,
h2,
h3 {
  margin-top: 0;
}

p {
  margin-bottom: 1rem;
}

.skip-link {
  position: absolute;
  left: 18px;
  top: -80px;
  z-index: 100;
  padding: 10px 14px;
  border-radius: var(--radius);
  background: var(--ember);
  color: #fff;
  font-weight: 800;
}

.skip-link:focus {
  top: 18px;
}

.side-rail {
  position: fixed;
  inset: 0 auto 0 0;
  z-index: 50;
  width: var(--rail);
  display: grid;
  grid-template-rows: auto auto 1fr;
  gap: 18px;
  padding: 26px 20px;
  border-right: 1px solid var(--line);
  background: rgba(10, 14, 14, 0.88);
  backdrop-filter: blur(18px);
}

.rail-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 44px;
  font-weight: 900;
  letter-spacing: 0;
}

.rail-brand img {
  width: 40px;
  height: 40px;
}

.rail-nav {
  display: grid;
  align-content: center;
  gap: 8px;
}

.rail-nav a {
  position: relative;
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 44px;
  padding: 10px 12px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  color: var(--muted);
  transition: color 0.2s ease, background 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
}

.rail-nav a span {
  color: var(--gold);
  font-size: 0.78rem;
  font-weight: 900;
}

.rail-nav a:hover,
.rail-nav a:focus-visible {
  transform: translateX(4px);
  border-color: rgba(232, 183, 93, 0.36);
  background: rgba(232, 183, 93, 0.08);
  color: var(--ink);
}

.rail-download {
  display: flex;
  justify-content: flex-start;
  align-items: center;
  gap: 12px;
  width: 100%;
  min-height: 44px;
  margin-top: 14px;
  padding: 10px 12px;
  border: 1px solid rgba(224, 82, 46, 0.38);
  border-radius: var(--radius);
  background: var(--ember);
  color: #fff;
  font-weight: 900;
  box-shadow: 0 16px 36px rgba(224, 82, 46, 0.28);
  transition: transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.rail-download span {
  color: #ffe3a5;
  font-size: 0.78rem;
  font-weight: 900;
}

.rail-download:hover,
.rail-download:focus-visible {
  transform: translateX(4px);
  background: #f1643d;
  box-shadow: 0 20px 46px rgba(224, 82, 46, 0.34);
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.05);
  color: var(--ink);
  padding: 10px;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  margin: 4px auto;
  background: currentColor;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.page-shell {
  width: calc(100% - var(--rail));
  margin-left: var(--rail);
}

main,
.site-footer {
  width: min(100% - 52px, 1160px);
  margin-inline: auto;
}

.briefing {
  min-height: 660px;
  display: grid;
  grid-template-columns: minmax(0, 0.85fr) minmax(420px, 1.15fr);
  grid-template-areas:
    "copy visual"
    "signals signals";
  gap: 34px;
  align-items: center;
  padding: 60px 0 42px;
}

.brief-copy {
  grid-area: copy;
}

.brief-visual {
  grid-area: visual;
  position: relative;
  min-height: 420px;
}

.signal-strip {
  grid-area: signals;
}

.label {
  margin-bottom: 12px;
  color: var(--gold);
  font-size: 0.82rem;
  font-weight: 900;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

h1,
h2 {
  color: var(--gold);
  background: linear-gradient(90deg, #fff7dc 0%, var(--gold) 58%, var(--ember) 100%);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}

h1 {
  max-width: 620px;
  margin-bottom: 18px;
  font-size: clamp(2.1rem, 5vw, 4.2rem);
  line-height: 1.02;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 0;
  font-size: clamp(1.55rem, 3vw, 2.55rem);
  line-height: 1.12;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 8px;
  font-size: 1.08rem;
}

.brief-text,
.copy-pane p,
.route-copy p,
.strategy-copy p,
.download-lane p,
.release-card p,
.faq-item p,
.index-row p,
.archive p {
  color: var(--muted);
}

.brief-text {
  max-width: 590px;
  font-size: 1.03rem;
}

.brief-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 22px;
}

.btn {
  position: relative;
  overflow: hidden;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 10px 17px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-weight: 900;
  line-height: 1.2;
  transition: transform 0.2s ease, background 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}

.btn::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(110deg, transparent 0%, rgba(255, 255, 255, 0.24) 48%, transparent 72%);
  opacity: 0;
  transform: translateX(-120%);
  transition: opacity 0.25s ease, transform 0.45s ease;
}

.btn:hover::before,
.btn:focus-visible::before {
  opacity: 1;
  transform: translateX(120%);
}

.btn:hover,
.btn:focus-visible {
  transform: translateY(-2px);
}

.btn.solid {
  background: var(--ember);
  color: #fff;
  box-shadow: 0 16px 36px rgba(224, 82, 46, 0.28);
}

.btn.solid:hover,
.btn.solid:focus-visible {
  background: #f1643d;
  box-shadow: 0 20px 46px rgba(224, 82, 46, 0.34);
}

.btn.ghost {
  border-color: rgba(244, 239, 226, 0.28);
  background: rgba(255, 255, 255, 0.06);
  color: var(--ink);
}

.btn.ghost:hover,
.btn.ghost:focus-visible {
  border-color: rgba(232, 183, 93, 0.64);
  background: rgba(232, 183, 93, 0.12);
}

.visual-main,
.visual-chip {
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  box-shadow: var(--shadow);
}

.visual-main {
  position: absolute;
  inset: 16px 0 38px 74px;
}

.visual-main img,
.visual-chip img,
.frame-image img,
.route-media img,
.download-lane img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.35s ease, filter 0.35s ease;
}

.visual-chip {
  position: absolute;
  width: 230px;
  height: 156px;
  z-index: 2;
}

.chip-one {
  left: 0;
  top: 0;
}

.chip-two {
  right: 20px;
  bottom: 0;
}

.visual-main:hover img,
.visual-chip:hover img,
.frame-image:hover img,
.route-media:hover img,
.download-lane figure:hover img {
  transform: scale(1.035);
  filter: saturate(1.08) contrast(1.04);
}

.signal-strip {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1px;
  margin: 0;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--line);
}

.signal-strip div {
  min-height: 86px;
  padding: 16px;
  background: rgba(21, 27, 27, 0.94);
  transition: background 0.2s ease, transform 0.2s ease;
}

.signal-strip div:hover {
  background: #202a28;
  transform: translateY(-2px);
}

.signal-strip dt {
  margin-bottom: 4px;
  color: var(--soft);
  font-size: 0.8rem;
}

.signal-strip dd {
  margin: 0;
  font-weight: 900;
}

.section {
  padding: 72px 0;
  border-top: 1px solid var(--line);
}

.section-head {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
  margin-bottom: 28px;
}

.section-head .label {
  margin-bottom: 6px;
}

.dossier-grid,
.route-map,
.strategy,
.download-lane {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(360px, 0.9fr);
  gap: 24px;
  align-items: stretch;
}

.copy-pane,
.route-copy,
.strategy-copy,
.download-lane > div {
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(21, 27, 27, 0.9);
}

.frame-image,
.route-media,
.download-lane figure {
  min-height: 320px;
  margin: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  box-shadow: var(--shadow);
}

.index-list {
  display: grid;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.index-row {
  display: grid;
  grid-template-columns: 220px minmax(0, 1fr);
  gap: 24px;
  padding: 20px 24px;
  background: rgba(21, 27, 27, 0.92);
  border-bottom: 1px solid var(--line);
  transition: transform 0.2s ease, background 0.2s ease;
}

.index-row:last-child {
  border-bottom: 0;
}

.index-row:hover {
  transform: translateX(5px);
  background: #202a28;
}

.index-row span {
  color: var(--gold);
  font-weight: 900;
}

.index-row p {
  margin: 0;
}

.route-map {
  grid-template-columns: minmax(360px, 0.9fr) minmax(0, 1fr);
}

.route-notes {
  display: grid;
  gap: 10px;
  padding: 0;
  margin: 22px 0 0;
  list-style: none;
}

.route-notes li {
  position: relative;
  padding-left: 24px;
  color: var(--muted);
}

.route-notes li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.72em;
  width: 10px;
  height: 10px;
  border: 2px solid var(--jade);
  border-radius: 50%;
  transform: translateY(-50%);
}

.ledger {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
}

.release-card {
  min-height: 210px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(21, 27, 27, 0.94);
  transition: transform 0.22s ease, border-color 0.22s ease, background 0.22s ease;
}

.release-card:hover {
  transform: translateY(-5px);
  border-color: rgba(232, 183, 93, 0.36);
  background: #202a28;
}

.release-card time {
  color: var(--gold);
  font-size: 0.86rem;
  font-weight: 900;
}

.archive {
  margin-top: 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.045);
}

.archive summary {
  cursor: pointer;
  padding: 15px 18px;
  font-weight: 900;
  transition: color 0.2s ease;
}

.archive summary:hover,
.archive summary:focus-visible {
  color: var(--gold);
}

.archive div {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  padding: 0 18px 18px;
}

.archive p {
  margin: 0;
  padding: 13px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(0, 0, 0, 0.16);
}

.strategy {
  align-items: start;
}

.strategy-copy {
  position: sticky;
  top: 24px;
}

.strategy-list {
  counter-reset: step;
  display: grid;
  gap: 10px;
  padding: 0;
  margin: 0;
  list-style: none;
}

.strategy-list li {
  counter-increment: step;
  position: relative;
  padding: 13px 16px 13px 52px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(21, 27, 27, 0.92);
  color: var(--muted);
  transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.strategy-list li::before {
  content: counter(step, decimal-leading-zero);
  position: absolute;
  left: 16px;
  top: 13px;
  color: var(--gold);
  font-weight: 900;
}

.strategy-list li:hover {
  transform: translateX(5px);
  border-color: rgba(114, 183, 149, 0.42);
  background: #202a28;
}

.download-lane {
  margin: 72px 0;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background:
    linear-gradient(135deg, rgba(224, 82, 46, 0.16), transparent 42%),
    rgba(21, 27, 27, 0.9);
  box-shadow: var(--shadow);
}

.download-lane figure {
  min-height: 260px;
}

.faq-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.faq-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(21, 27, 27, 0.94);
  transition: transform 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}

.faq-item:hover {
  transform: translateY(-3px);
  border-color: rgba(232, 183, 93, 0.34);
  background: #202a28;
}

.faq-item summary {
  cursor: pointer;
  padding: 15px 18px;
  font-weight: 900;
  transition: color 0.2s ease;
}

.faq-item summary:hover,
.faq-item summary:focus-visible {
  color: var(--gold);
}

.faq-item p {
  margin: 0;
  padding: 0 18px 16px;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 30px 0 46px;
  border-top: 1px solid var(--line);
}

.site-footer p {
  max-width: 720px;
  margin: 8px 0 0;
  color: var(--soft);
  font-size: 0.92rem;
}

.site-footer a {
  color: var(--gold);
  font-weight: 900;
  white-space: nowrap;
  transition: color 0.2s ease, transform 0.2s ease;
}

.site-footer a:hover,
.site-footer a:focus-visible {
  color: #ffd47d;
  transform: translateY(-1px);
}

.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 0.55s ease, transform 0.55s ease;
}

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

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }

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

@media (max-width: 1120px) {
  :root {
    --rail: 0px;
  }

  .side-rail {
    inset: 0 0 auto;
    width: auto;
    min-height: 68px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 12px 18px;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .nav-toggle {
    display: inline-block;
  }

  .rail-nav {
    position: fixed;
    left: 18px;
    right: 18px;
    top: 78px;
    display: none;
    padding: 14px;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: rgba(10, 14, 14, 0.98);
    box-shadow: var(--shadow);
  }

  .rail-nav.is-open {
    display: grid;
  }

  .rail-download {
    min-width: 80px;
    padding-inline: 14px;
  }

  .nav-open .nav-toggle span:nth-child(1) {
    transform: translateY(6px) rotate(45deg);
  }

  .nav-open .nav-toggle span:nth-child(2) {
    opacity: 0;
  }

  .nav-open .nav-toggle span:nth-child(3) {
    transform: translateY(-6px) rotate(-45deg);
  }

  .page-shell {
    width: 100%;
    margin-left: 0;
    padding-top: 68px;
  }

  .briefing {
    min-height: auto;
    grid-template-columns: 1fr;
    grid-template-areas:
      "copy"
      "visual"
      "signals";
    padding-top: 42px;
  }

  .brief-visual {
    min-height: 450px;
  }

  .ledger {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 760px) {
  body {
    font-size: 14px;
  }

  main,
  .site-footer {
    width: min(100% - 28px, 1160px);
  }

  .rail-brand span {
    font-size: 0.98rem;
  }

  .rail-download {
    display: none;
  }

  .briefing,
  .section,
  .download-lane {
    padding-block: 46px;
  }

  .brief-visual {
    min-height: 340px;
  }

  .visual-main {
    inset: 34px 0 34px 0;
  }

  .visual-chip {
    width: 150px;
    height: 102px;
  }

  .chip-two {
    right: 0;
  }

  .signal-strip,
  .dossier-grid,
  .route-map,
  .strategy,
  .download-lane,
  .faq-grid,
  .archive div {
    grid-template-columns: 1fr;
  }

  .index-row {
    grid-template-columns: 1fr;
    gap: 8px;
    padding: 18px;
  }

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

  .section-head,
  .site-footer {
    align-items: flex-start;
    flex-direction: column;
  }

  .strategy-copy {
    position: static;
  }

  .frame-image,
  .route-media,
  .download-lane figure {
    min-height: 230px;
  }

  .copy-pane,
  .route-copy,
  .strategy-copy,
  .download-lane > div {
    padding: 22px;
  }

  .btn {
    width: 100%;
  }
}

@media (max-width: 430px) {
  h1 {
    font-size: 2rem;
  }

  h2 {
    font-size: 1.55rem;
  }

  .brief-visual {
    min-height: 300px;
  }

  .visual-chip {
    display: none;
  }
}