:root {
  --bg: #0f0f10;
  --bg-deep: #070707;
  --paper: #fff7ea;
  --ink: #17120f;
  --muted: #6f6861;
  --line: rgba(255, 255, 255, 0.16);
  --line-dark: rgba(23, 18, 15, 0.12);
  --red: #d6251f;
  --red-dark: #8f1715;
  --amber: #ffb323;
  --orange: #f06d1e;
  --white: #ffffff;
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.34);
  --radius: 8px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--paper);
  font-family: "Microsoft YaHei", "PingFang SC", "Hiragino Sans GB", Arial, sans-serif;
  font-size: 15px;
  line-height: 1.65;
  text-rendering: optimizeLegibility;
}

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

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

:focus-visible {
  outline: 2px solid var(--amber);
  outline-offset: 4px;
}

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

.skip-link {
  position: absolute;
  left: 16px;
  top: -80px;
  z-index: 1000;
  background: var(--amber);
  color: var(--ink);
  padding: 10px 14px;
  border-radius: 6px;
  font-weight: 700;
}

.skip-link:focus {
  top: 16px;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 900;
  border-bottom: 1px solid transparent;
  background: linear-gradient(180deg, rgba(8, 8, 8, 0.82), rgba(8, 8, 8, 0.38));
  backdrop-filter: blur(12px);
  transition: background 180ms ease, border-color 180ms ease;
}

.site-header.is-scrolled {
  border-color: rgba(255, 255, 255, 0.1);
  background: rgba(8, 8, 8, 0.9);
}

.nav-wrap {
  width: min(var(--max), calc(100% - 40px));
  height: 64px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 900;
  letter-spacing: 0;
  transition: transform 180ms ease;
}

.brand:hover {
  transform: translateY(-1px);
}

.brand-mark {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  background: var(--red);
  color: var(--white);
  border: 2px solid rgba(255, 255, 255, 0.82);
  transform: skew(-8deg);
  box-shadow: 6px 6px 0 rgba(255, 179, 35, 0.72);
  transition: box-shadow 180ms ease, transform 180ms ease;
}

.brand:hover .brand-mark {
  transform: skew(-8deg) rotate(-3deg);
  box-shadow: 4px 4px 0 rgba(255, 179, 35, 0.9);
}

.brand-text {
  font-size: 16px;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 22px;
  color: rgba(255, 255, 255, 0.78);
  font-size: 13px;
}

.nav-links a {
  position: relative;
  padding: 8px 0;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 4px;
  width: 0;
  height: 2px;
  background: var(--amber);
  transition: width 180ms ease;
}

.nav-links a:hover,
.nav-links a.is-active {
  color: var(--white);
}

.nav-links a:hover::after,
.nav-links a.is-active::after {
  width: 100%;
}

.nav-links .nav-cta {
  min-height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 16px;
  border-radius: 6px;
  background: var(--red);
  color: var(--white);
  font-weight: 900;
  box-shadow: 4px 4px 0 rgba(255, 179, 35, 0.82);
  transition: transform 180ms ease, background 180ms ease, box-shadow 180ms ease;
}

.nav-links .nav-cta::after {
  display: none;
}

.nav-links .nav-cta:hover,
.nav-links .nav-cta.is-active {
  color: var(--white);
  background: #f02b22;
  transform: translateY(-2px);
  box-shadow: 3px 3px 0 rgba(255, 179, 35, 0.96), 0 10px 24px rgba(214, 37, 31, 0.24);
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  position: relative;
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: 6px;
  background: rgba(255, 255, 255, 0.05);
  padding: 0;
  cursor: pointer;
  transition: background 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
}

.nav-toggle:hover {
  background: rgba(255, 255, 255, 0.12);
  border-color: rgba(255, 179, 35, 0.7);
  box-shadow: 0 0 0 4px rgba(255, 179, 35, 0.12);
}

.nav-toggle span {
  display: block;
  position: absolute;
  left: 10px;
  width: 20px;
  height: 2px;
  background: var(--white);
  transition: opacity 180ms ease, transform 180ms ease;
  transform-origin: center;
}

.nav-toggle span:nth-child(1) {
  top: 13px;
}

.nav-toggle span:nth-child(2) {
  top: 20px;
}

.nav-toggle span:nth-child(3) {
  top: 27px;
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] span:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.hero {
  position: relative;
  min-height: 650px;
  display: grid;
  align-items: center;
  overflow: hidden;
  isolation: isolate;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}

.hero-media,
.hero-media picture,
.hero-media img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-media img {
  object-fit: cover;
  object-position: center;
  filter: saturate(1.08) contrast(1.08);
  transform: scale(1.02);
}

.hero-overlay {
  position: absolute;
  inset: 0;
  z-index: 1;
  background:
    linear-gradient(90deg, rgba(7, 7, 7, 0.98) 0%, rgba(7, 7, 7, 0.82) 34%, rgba(7, 7, 7, 0.24) 72%, rgba(7, 7, 7, 0.76) 100%),
    linear-gradient(180deg, rgba(7, 7, 7, 0.1) 0%, rgba(7, 7, 7, 0.92) 100%);
}

.hero::after {
  content: "";
  position: absolute;
  z-index: 2;
  left: -8%;
  bottom: 15%;
  width: 70%;
  height: 150px;
  background: linear-gradient(90deg, rgba(214, 37, 31, 0), rgba(214, 37, 31, 0.7), rgba(255, 179, 35, 0));
  transform: skewY(-10deg);
  opacity: 0.7;
  pointer-events: none;
}

.hero-content {
  position: relative;
  z-index: 3;
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
  padding: 82px 0 30px;
  transform: translateY(-22px);
}

.eyebrow,
.section-kicker {
  margin: 0 0 14px;
  color: var(--amber);
  font-size: 13px;
  font-weight: 900;
  text-transform: uppercase;
  letter-spacing: 0;
}

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

h1 {
  max-width: 800px;
  margin-bottom: 14px;
  color: var(--white);
  font-size: clamp(28px, 4.4vw, 56px);
  line-height: 0.95;
  font-weight: 950;
  letter-spacing: 0;
  text-shadow: 8px 8px 0 rgba(214, 37, 31, 0.72);
}

.hero-subtitle {
  max-width: 670px;
  margin-bottom: 22px;
  color: rgba(255, 255, 255, 0.86);
  font-size: clamp(16px, 1.7vw, 20px);
  line-height: 1.65;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
  margin-bottom: 26px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 42px;
  padding: 10px 18px;
  border-radius: 6px;
  font-weight: 900;
  line-height: 1.2;
  position: relative;
  overflow: hidden;
  transition: transform 180ms ease, background 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
}

.btn::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(100deg, transparent 0%, rgba(255, 255, 255, 0.24) 45%, transparent 70%);
  transform: translateX(-120%);
  transition: transform 420ms ease;
  pointer-events: none;
}

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

.btn:hover::after {
  transform: translateX(120%);
}

.btn-primary {
  background: var(--red);
  color: var(--white);
  border: 1px solid rgba(255, 255, 255, 0.18);
  box-shadow: 7px 7px 0 rgba(255, 179, 35, 0.9);
}

.btn-primary:hover {
  background: #f02b22;
  box-shadow: 5px 5px 0 rgba(255, 179, 35, 0.96), 0 14px 34px rgba(214, 37, 31, 0.24);
}

.btn-secondary {
  border: 1px solid rgba(255, 255, 255, 0.28);
  color: var(--white);
  background: rgba(255, 255, 255, 0.08);
}

.btn-secondary:hover {
  border-color: rgba(255, 179, 35, 0.72);
  background: rgba(255, 255, 255, 0.14);
}

.btn-large {
  min-height: 48px;
  padding-inline: 24px;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 150px));
  gap: 10px;
  max-width: 470px;
  margin: 0;
}

.hero-stats div {
  border: 1px solid rgba(255, 255, 255, 0.18);
  background: rgba(255, 255, 255, 0.08);
  padding: 11px 14px;
  border-radius: var(--radius);
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

.hero-stats div:hover {
  transform: translateY(-2px);
  border-color: rgba(255, 179, 35, 0.52);
  background: rgba(255, 255, 255, 0.12);
}

.hero-stats dt {
  color: rgba(255, 255, 255, 0.58);
  font-size: 12px;
}

.hero-stats dd {
  margin: 2px 0 0;
  color: var(--white);
  font-weight: 900;
}

.section {
  padding: 72px 0;
  background: var(--paper);
  color: var(--ink);
}

.section-grid,
.systems-layout,
.footer-inner {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
}

.section-grid {
  display: grid;
  grid-template-columns: 1fr minmax(320px, 500px);
  gap: 42px;
  align-items: center;
}

.section-copy h2,
.section-head h2,
.systems-copy h2,
.download-inner h2 {
  position: relative;
  margin-bottom: 12px;
  padding-bottom: 9px;
  color: var(--red);
  font-size: clamp(20px, 2.3vw, 30px);
  line-height: 1.12;
  font-weight: 950;
  letter-spacing: 0;
}

.section-copy h2::after,
.section-head h2::after,
.systems-copy h2::after,
.download-inner h2::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 44px;
  height: 3px;
  border-radius: 999px;
  background: linear-gradient(90deg, var(--red), var(--amber));
}

.dark-band .section-head h2,
.systems-copy h2,
.download-inner h2 {
  color: var(--amber);
}

.download-inner h2::after {
  left: 50%;
  transform: translateX(-50%);
}

.section-copy p,
.section-head p,
.systems-copy p,
.download-inner p {
  color: var(--muted);
  font-size: 15px;
}

.keyword-line {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 20px;
}

.keyword-line span {
  border: 1px solid var(--line-dark);
  background: rgba(214, 37, 31, 0.08);
  color: var(--red-dark);
  border-radius: 999px;
  padding: 7px 10px;
  font-weight: 800;
  font-size: 13px;
}

figure {
  margin: 0;
}

figcaption {
  margin-top: 12px;
  color: rgba(23, 18, 15, 0.64);
  font-size: 13px;
}

.feature-image img,
.strip-card img,
.systems-image img,
.wide-shot img {
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  border: 1px solid rgba(23, 18, 15, 0.1);
  transition: transform 220ms ease, filter 220ms ease, box-shadow 220ms ease;
}

.feature-image:hover img,
.strip-card:hover img,
.systems-image:hover img,
.wide-shot:hover img {
  transform: translateY(-4px) scale(1.01);
  filter: saturate(1.08) contrast(1.04);
  box-shadow: 0 28px 74px rgba(0, 0, 0, 0.42);
}

.dark-band {
  background:
    linear-gradient(135deg, rgba(214, 37, 31, 0.2), rgba(15, 15, 16, 0) 38%),
    var(--bg-deep);
  color: var(--paper);
}

.dark-band .section-head p,
.dark-band figcaption {
  color: rgba(255, 247, 234, 0.68);
}

.section-head {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto 32px;
}

.section-head h2 {
  max-width: 820px;
}

.section-head p {
  max-width: 820px;
}

.feature-cards,
.route-grid,
.update-grid {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.feature-card,
.route-card,
.update-card,
.timeline-item {
  border-radius: var(--radius);
  border: 1px solid rgba(255, 255, 255, 0.13);
  background: rgba(255, 255, 255, 0.06);
  padding: 20px;
  transition: transform 200ms ease, border-color 200ms ease, background 200ms ease, box-shadow 200ms ease;
}

.feature-card:hover,
.route-card:hover {
  transform: translateY(-5px);
  border-color: rgba(255, 179, 35, 0.44);
  background: rgba(255, 255, 255, 0.09);
  box-shadow: 0 18px 42px rgba(0, 0, 0, 0.24);
}

.update-card:hover,
.timeline-item:hover {
  transform: translateY(-4px);
  border-color: rgba(214, 37, 31, 0.24);
  box-shadow: 0 16px 42px rgba(23, 18, 15, 0.12);
}

.feature-card {
  min-height: 220px;
}

.feature-card h3,
.route-card h3,
.update-card h3,
.timeline-item h3,
.system-list h3 {
  margin-bottom: 8px;
  font-size: 18px;
  line-height: 1.25;
  letter-spacing: 0;
}

.feature-card p,
.route-card p,
.update-card p,
.timeline-item p,
.system-list p {
  margin-bottom: 0;
}

.feature-card p,
.route-card p,
.update-card p {
  color: rgba(255, 247, 234, 0.72);
}

.card-index {
  display: block;
  margin-bottom: 16px;
  color: var(--amber);
  font-size: 28px;
  line-height: 1;
  font-weight: 950;
}

.image-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 18px;
  padding-inline: max(20px, calc((100vw - var(--max)) / 2));
}

.strip-card {
  min-width: 0;
}

.strip-card img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
}

.guide-section {
  background:
    linear-gradient(180deg, rgba(255, 179, 35, 0.12), rgba(255, 247, 234, 0) 45%),
    var(--paper);
}

.timeline {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 14px;
}

.timeline-item {
  position: relative;
  border-color: var(--line-dark);
  background: #fffaf2;
  color: var(--ink);
}

.timeline-item::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 5px;
  background: linear-gradient(90deg, var(--red), var(--amber));
  border-radius: var(--radius) var(--radius) 0 0;
}

.timeline-item span {
  display: inline-block;
  margin-bottom: 10px;
  color: var(--red-dark);
  font-size: 13px;
  font-weight: 900;
}

.timeline-item p,
.system-list p {
  color: var(--muted);
}

.systems-section {
  background: #120f0d;
  color: var(--paper);
}

.systems-layout {
  display: grid;
  grid-template-columns: minmax(320px, 1fr) 0.95fr;
  gap: 42px;
  align-items: center;
}

.systems-image figcaption {
  color: rgba(255, 247, 234, 0.62);
}

.system-list {
  display: grid;
  gap: 14px;
  margin-top: 20px;
}

.system-list article {
  padding: 15px;
  border-radius: var(--radius);
  border: 1px solid rgba(255, 255, 255, 0.14);
  background: rgba(255, 255, 255, 0.06);
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

.system-list article:hover {
  transform: translateX(4px);
  border-color: rgba(255, 179, 35, 0.42);
  background: rgba(255, 255, 255, 0.09);
}

.systems-copy p {
  color: rgba(255, 247, 234, 0.72);
}

.routes-section {
  padding-bottom: 68px;
}

.route-grid {
  grid-template-columns: repeat(4, 1fr);
  margin-bottom: 32px;
}

.route-card {
  min-height: 178px;
}

.wide-shot {
  width: min(860px, calc(100% - 40px));
  margin: 0 auto;
}

.wide-shot img {
  width: 100%;
}

.update-section {
  background: var(--paper);
}

.update-grid {
  grid-template-columns: repeat(3, 1fr);
}

.update-card {
  border-color: var(--line-dark);
  background: #fffaf2;
  color: var(--ink);
}

.update-card p {
  color: var(--muted);
}

.download-section {
  position: relative;
  overflow: hidden;
  background:
    linear-gradient(100deg, rgba(7, 7, 7, 0.95), rgba(7, 7, 7, 0.76)),
    url("img/tu6.jpg") center / cover no-repeat;
  color: var(--white);
  padding: 76px 20px;
}

.download-section::before {
  content: "";
  position: absolute;
  inset: auto -10% 0 -10%;
  height: 130px;
  background: var(--red);
  transform: skewY(-4deg) translateY(70px);
}

.download-inner {
  position: relative;
  width: min(820px, 100%);
  margin: 0 auto;
  text-align: center;
}

.download-inner p {
  color: rgba(255, 255, 255, 0.78);
  margin-bottom: 22px;
}

.faq-section {
  background: #fffaf2;
}

.faq-list {
  width: min(920px, calc(100% - 40px));
  margin: 0 auto;
  display: grid;
  gap: 12px;
}

.faq-item {
  border: 1px solid var(--line-dark);
  border-radius: var(--radius);
  background: var(--white);
  overflow: hidden;
  transition: border-color 180ms ease, box-shadow 180ms ease, transform 180ms ease;
}

.faq-item:hover {
  transform: translateY(-2px);
  border-color: rgba(214, 37, 31, 0.26);
  box-shadow: 0 14px 34px rgba(23, 18, 15, 0.1);
}

.faq-item button {
  width: 100%;
  min-height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 15px 20px;
  border: 0;
  background: transparent;
  color: var(--ink);
  text-align: left;
  font: inherit;
  font-weight: 900;
  cursor: pointer;
  transition: color 180ms ease, background 180ms ease;
}

.faq-item button:hover {
  color: var(--red-dark);
  background: rgba(214, 37, 31, 0.04);
}

.faq-item button::after {
  content: "+";
  flex: 0 0 auto;
  width: 26px;
  height: 26px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--red);
  color: var(--white);
  font-weight: 900;
  line-height: 1;
}

.faq-item button[aria-expanded="true"]::after {
  content: "-";
}

.faq-panel {
  max-height: 0;
  overflow: hidden;
  transition: max-height 220ms ease;
}

.faq-item.is-open .faq-panel {
  max-height: 220px;
}

.faq-panel p {
  margin: 0;
  padding: 0 20px 16px;
  color: var(--muted);
}

.site-footer {
  background: var(--bg-deep);
  color: rgba(255, 247, 234, 0.72);
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  padding: 34px 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.footer-inner strong {
  color: var(--white);
  font-size: 16px;
}

.footer-inner p {
  max-width: 560px;
  margin: 6px 0 0;
}

.footer-inner nav {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  font-size: 13px;
}

.footer-inner a:hover {
  color: var(--amber);
}

.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity 520ms ease, transform 520ms ease;
}

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

.hero-content.reveal {
  transform: translateY(-8px);
}

.hero-content.reveal.is-visible {
  transform: translateY(-22px);
}

@media (max-width: 1080px) {
  .feature-cards,
  .route-grid {
    grid-template-columns: repeat(2, 1fr);
  }

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

@media (max-width: 860px) {
  .nav-toggle {
    display: block;
  }

  .nav-links {
    position: absolute;
    left: 20px;
    right: 20px;
    top: 64px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px;
    border: 1px solid rgba(255, 255, 255, 0.14);
    border-radius: var(--radius);
    background: rgba(8, 8, 8, 0.96);
  }

  .nav-links.is-open {
    display: flex;
  }

  .nav-links a {
    padding: 12px;
  }

  .hero {
    min-height: 590px;
  }

  .hero-overlay {
    background:
      linear-gradient(180deg, rgba(7, 7, 7, 0.48), rgba(7, 7, 7, 0.96) 82%),
      linear-gradient(90deg, rgba(7, 7, 7, 0.9), rgba(7, 7, 7, 0.2));
  }

  h1 {
    text-shadow: 5px 5px 0 rgba(214, 37, 31, 0.72);
  }

  .section-grid,
  .systems-layout {
    grid-template-columns: 1fr;
  }

  .image-strip {
    grid-template-columns: 1fr;
  }

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

@media (max-width: 620px) {
  .nav-wrap,
  .section-grid,
  .systems-layout,
  .section-head,
  .feature-cards,
  .route-grid,
  .timeline,
  .update-grid,
  .faq-list,
  .footer-inner,
  .hero-content {
    width: min(100% - 28px, var(--max));
  }

  .hero-content {
    padding-top: 76px;
    padding-bottom: 24px;
    transform: translateY(-10px);
  }

  .hero-content.reveal.is-visible {
    transform: translateY(-10px);
  }

  .hero-stats,
  .feature-cards,
  .route-grid,
  .timeline {
    grid-template-columns: 1fr;
  }

  .section,
  .download-section {
    padding-top: 56px;
    padding-bottom: 56px;
  }

  .hero-actions {
    align-items: stretch;
  }

  .btn {
    width: 100%;
  }

  .feature-card,
  .route-card,
  .timeline-item {
    min-height: auto;
  }

  .footer-inner {
    align-items: flex-start;
    flex-direction: column;
  }
}

@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;
  }
}