:root {
  --bg: #0f172a;
  --bg-deep: #0b1120;
  --police-blue: #1e293b;
  --metal: #1f2937;
  --cyan: #0ea5e9;
  --cyan-soft: rgba(14, 165, 233, 0.18);
  --violet: #701a75;
  --violet-deep: #581c87;
  --alert: #ef4444;
  --silver: #e2e8f0;
  --muted: #a7b1c2;
  --line: rgba(226, 232, 240, 0.16);
  --shadow: 0 24px 70px rgba(2, 6, 23, 0.5);
  --radius: 8px;
  --container: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 88px;
}

body {
  margin: 0;
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans SC", Arial, sans-serif;
  color: var(--silver);
  background:
    linear-gradient(180deg, rgba(15, 23, 42, 0.98), rgba(11, 17, 32, 1) 42%, #111827 100%),
    repeating-linear-gradient(90deg, rgba(226, 232, 240, 0.035) 0 1px, transparent 1px 74px);
  line-height: 1.7;
  letter-spacing: 0;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background:
    linear-gradient(120deg, rgba(14, 165, 233, 0.08), transparent 32%),
    linear-gradient(300deg, rgba(112, 26, 117, 0.16), transparent 42%);
}

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

.ui-icon {
  width: 1.1em;
  height: 1.1em;
  flex: 0 0 auto;
  object-fit: contain;
  filter: brightness(0) invert(1);
  opacity: 0.92;
}

.nav-icon {
  width: 16px;
  height: 16px;
}

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

p {
  margin: 0 0 16px;
}

strong {
  color: #fff;
}

.container {
  width: min(100% - 40px, var(--container));
  margin-inline: auto;
}

.skip-link {
  position: fixed;
  left: 16px;
  top: 14px;
  z-index: 1000;
  transform: translateY(-140%);
  padding: 10px 14px;
  color: #07111e;
  background: var(--silver);
  border-radius: 6px;
  font-weight: 700;
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 10px max(20px, calc((100vw - var(--container)) / 2));
  background: rgba(11, 17, 32, 0.78);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(16px);
}

.site-header.is-scrolled {
  background: rgba(11, 17, 32, 0.94);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 0;
  font-weight: 800;
  color: #fff;
}

.brand img {
  width: 48px;
  height: 52px;
  object-fit: cover;
  border: 1px solid rgba(226, 232, 240, 0.28);
  border-radius: 6px;
}

.brand span {
  max-width: 180px;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 6px;
}

.site-nav a {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  padding: 8px 12px;
  border: 1px solid transparent;
  border-radius: 999px;
  color: var(--muted);
  font-size: 15px;
  transition: color 180ms ease, border-color 180ms ease, background 180ms ease, box-shadow 180ms ease, transform 180ms ease;
}

.site-nav a:hover,
.site-nav a.is-active {
  color: #f8fbff;
  border-color: rgba(14, 165, 233, 0.72);
  background: rgba(14, 165, 233, 0.08);
  box-shadow: 0 0 0 1px rgba(226, 232, 240, 0.06), 0 0 18px rgba(14, 165, 233, 0.18);
  text-shadow: 0 0 12px rgba(125, 211, 252, 0.65);
}

.site-nav .nav-cta {
  margin-left: 8px;
  color: #fff;
  background: linear-gradient(135deg, var(--alert), var(--violet));
  border: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow: 0 12px 34px rgba(239, 68, 68, 0.28);
}

.site-nav .nav-cta:hover,
.site-nav .nav-cta.is-active {
  color: #fff;
  border-color: rgba(255, 255, 255, 0.32);
  background: linear-gradient(135deg, var(--alert), var(--violet));
  box-shadow: 0 16px 38px rgba(239, 68, 68, 0.34);
  text-shadow: none;
  transform: translateY(-2px);
}

.nav-toggle {
  display: none;
  width: 46px;
  height: 42px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: rgba(226, 232, 240, 0.08);
  color: #fff;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  margin: 4px auto;
  background: currentColor;
  transition: transform 180ms ease, opacity 180ms ease;
}

.nav-toggle b {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
}

.nav-toggle[aria-expanded="true"] span:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}

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

.nav-toggle[aria-expanded="true"] span:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

.hero {
  position: relative;
  min-height: 86svh;
  display: grid;
  align-items: center;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
}

.hero-bg,
.hero-shade {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-bg {
  object-fit: cover;
  object-position: center;
}

.hero-shade {
  background:
    linear-gradient(90deg, rgba(11, 17, 32, 0.94) 0%, rgba(11, 17, 32, 0.74) 42%, rgba(11, 17, 32, 0.28) 100%),
    linear-gradient(0deg, rgba(11, 17, 32, 0.92), rgba(11, 17, 32, 0.12) 46%, rgba(11, 17, 32, 0.55));
}

.hero-inner {
  position: relative;
  z-index: 1;
  padding: 120px 0 58px;
  max-width: 920px;
}

.eyebrow,
.section-kicker {
  margin: 0 0 12px;
  color: #7dd3fc;
  font-size: 14px;
  font-weight: 800;
  text-transform: uppercase;
}

h1,
h2,
h3 {
  margin: 0;
  color: #fff;
  line-height: 1.2;
  letter-spacing: 0;
}

h1 {
  max-width: 760px;
  font-size: 52px;
  font-weight: 900;
}

.hero-lead {
  max-width: 720px;
  margin-top: 22px;
  color: #d7deea;
  font-size: 18px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.btn {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px 20px;
  border-radius: 999px;
  font-weight: 800;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 180ms ease, border-color 180ms ease, box-shadow 180ms ease, background 180ms ease;
}

.btn-primary {
  color: #fff;
  background: linear-gradient(135deg, var(--alert), var(--violet));
  box-shadow: 0 18px 45px rgba(239, 68, 68, 0.28);
}

.btn-primary:hover {
  border-color: rgba(255, 255, 255, 0.34);
  box-shadow: 0 24px 56px rgba(239, 68, 68, 0.38), 0 0 24px rgba(112, 26, 117, 0.34);
  filter: saturate(1.12) brightness(1.05);
}

.btn-secondary {
  color: #fff;
  background: rgba(226, 232, 240, 0.08);
  border-color: rgba(226, 232, 240, 0.22);
}

.btn-secondary:hover {
  border-color: rgba(14, 165, 233, 0.72);
  background: rgba(14, 165, 233, 0.13);
  box-shadow: 0 18px 42px rgba(14, 165, 233, 0.18);
}

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

.hero-facts {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
  max-width: 760px;
  margin: 34px 0 0;
}

.hero-facts div {
  min-height: 88px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(15, 23, 42, 0.62);
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease, box-shadow 180ms ease;
}

.hero-facts div:hover {
  transform: translateY(-3px);
  border-color: rgba(14, 165, 233, 0.62);
  background: rgba(15, 23, 42, 0.78);
  box-shadow: 0 18px 42px rgba(14, 165, 233, 0.14);
}

.hero-facts dt {
  color: var(--muted);
  font-size: 13px;
}

.hero-facts dd {
  margin: 6px 0 0;
  color: #fff;
  font-size: 16px;
  font-weight: 800;
}

.signal-band {
  background: linear-gradient(90deg, rgba(30, 41, 59, 0.98), rgba(31, 41, 55, 0.98));
  border-bottom: 1px solid var(--line);
}

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

.signal-grid article {
  min-height: 118px;
  padding: 24px;
  background: rgba(15, 23, 42, 0.42);
  transition: transform 180ms ease, background 180ms ease, box-shadow 180ms ease;
}

.signal-grid article:hover {
  transform: translateY(-2px);
  background: rgba(15, 23, 42, 0.66);
  box-shadow: inset 0 0 0 1px rgba(14, 165, 233, 0.32), 0 18px 42px rgba(2, 6, 23, 0.22);
}

.signal-grid strong,
.signal-grid span {
  display: block;
}

.signal-grid span {
  margin-top: 8px;
  color: var(--muted);
}

.section {
  padding: 92px 0;
}

.section:nth-of-type(odd) {
  background: rgba(30, 41, 59, 0.18);
}

.section-head {
  max-width: 860px;
  margin-bottom: 32px;
}

.section-head h2,
.section-copy h2 {
  font-size: 34px;
}

.section-head p,
.section-copy p,
.topic-card p,
.guide-step p,
.feature-list p,
.timeline span,
.faq-list p {
  color: #c7d1df;
}

.section-split {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(320px, 0.78fr);
  gap: 42px;
  align-items: center;
}

.section-split.reverse {
  grid-template-columns: minmax(320px, 0.82fr) minmax(0, 1fr);
}

.media-panel,
.wide-media,
.gallery-main {
  margin: 0;
}

.media-panel img,
.wide-media img,
.gallery-main img {
  border-radius: var(--radius);
  border: 1px solid rgba(226, 232, 240, 0.18);
  box-shadow: var(--shadow);
  transition: transform 220ms ease, filter 220ms ease, border-color 220ms ease, box-shadow 220ms ease;
}

.media-panel:hover img,
.wide-media:hover img,
.gallery-main:hover img {
  transform: scale(1.012);
  filter: brightness(1.08) contrast(1.05) saturate(1.08);
  border-color: rgba(14, 165, 233, 0.52);
  box-shadow: 0 28px 78px rgba(2, 6, 23, 0.58), 0 0 28px rgba(14, 165, 233, 0.16);
}

figcaption {
  margin-top: 10px;
  color: var(--muted);
  font-size: 14px;
}

.content-layout {
  display: grid;
  gap: 28px;
}

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

.topic-grid,
.guide-grid,
.feature-list {
  display: grid;
  gap: 16px;
}

.topic-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.topic-card,
.guide-step,
.feature-list article,
.faq-list details {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(15, 23, 42, 0.72);
  position: relative;
  overflow: hidden;
  transition: transform 190ms ease, border-color 190ms ease, background 190ms ease, box-shadow 190ms ease;
}

.topic-card,
.guide-step,
.feature-list article {
  padding: 22px;
}

.topic-card:hover,
.guide-step:hover,
.feature-list article:hover,
.faq-list details:hover {
  transform: translateY(-4px);
  border-color: rgba(14, 165, 233, 0.56);
  background:
    linear-gradient(135deg, rgba(14, 165, 233, 0.11), rgba(112, 26, 117, 0.12)),
    rgba(15, 23, 42, 0.86);
  box-shadow: 0 20px 54px rgba(2, 6, 23, 0.34), 0 0 0 1px rgba(226, 232, 240, 0.04);
}

.topic-card h3,
.guide-step h3,
.feature-list h3 {
  margin-bottom: 10px;
  font-size: 20px;
}

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

.route-list li {
  padding: 13px 14px;
  border-left: 3px solid var(--cyan);
  background: rgba(14, 165, 233, 0.09);
  border-radius: 0 6px 6px 0;
  color: #d8e0eb;
  transition: transform 180ms ease, background 180ms ease, border-color 180ms ease, box-shadow 180ms ease;
}

.route-list li:hover {
  transform: translateX(4px);
  border-left-color: #7dd3fc;
  background: rgba(14, 165, 233, 0.16);
  box-shadow: 0 12px 28px rgba(14, 165, 233, 0.11);
}

.guide-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.guide-step span {
  display: inline-flex;
  width: 42px;
  height: 42px;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  color: #fff;
  background: linear-gradient(135deg, var(--cyan), var(--violet-deep));
  border-radius: 8px;
  font-weight: 900;
}

.feature-list {
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin-top: 24px;
}

.gallery {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(280px, 390px);
  gap: 18px;
  align-items: stretch;
}

.gallery-main {
  display: grid;
  align-content: start;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(15, 23, 42, 0.64);
}

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

.gallery-main figcaption {
  min-height: 34px;
  padding: 0 4px;
}

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

.gallery-thumb {
  width: 100%;
  min-width: 0;
  padding: 6px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: rgba(15, 23, 42, 0.78);
  cursor: pointer;
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease;
}

.gallery-thumb:hover {
  border-color: rgba(14, 165, 233, 0.72);
  background:
    linear-gradient(135deg, rgba(14, 165, 233, 0.12), rgba(112, 26, 117, 0.14)),
    rgba(15, 23, 42, 0.88);
  box-shadow: 0 14px 34px rgba(14, 165, 233, 0.14);
}

.gallery-thumb img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  border-radius: 6px;
}

.gallery-thumb.is-active {
  border-color: rgba(14, 165, 233, 0.82);
  background:
    linear-gradient(135deg, rgba(14, 165, 233, 0.18), rgba(112, 26, 117, 0.22)),
    rgba(15, 23, 42, 0.9);
  box-shadow: 0 0 0 2px rgba(14, 165, 233, 0.18);
}

.timeline {
  display: grid;
  gap: 12px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.timeline li {
  display: grid;
  grid-template-columns: 120px minmax(170px, 260px) minmax(0, 1fr);
  gap: 16px;
  align-items: start;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(15, 23, 42, 0.72);
  transition: transform 180ms ease, border-color 180ms ease, background 180ms ease, box-shadow 180ms ease;
}

.timeline li:hover {
  transform: translateX(4px);
  border-color: rgba(14, 165, 233, 0.58);
  background: rgba(15, 23, 42, 0.9);
  box-shadow: 0 16px 42px rgba(2, 6, 23, 0.28), inset 4px 0 0 rgba(14, 165, 233, 0.72);
}

.timeline time {
  color: #7dd3fc;
  font-weight: 900;
}

.timeline strong {
  font-size: 17px;
}

.faq-list {
  display: grid;
  gap: 12px;
}

.faq-list details {
  overflow: hidden;
}

.faq-list summary {
  min-height: 56px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 16px 18px;
  color: #fff;
  cursor: pointer;
  font-weight: 800;
  transition: color 180ms ease, background 180ms ease;
}

.faq-list details:hover summary {
  color: #f8fbff;
  background: rgba(14, 165, 233, 0.07);
}

.faq-list summary::after {
  content: "+";
  flex: 0 0 auto;
  width: 28px;
  height: 28px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
  background: var(--cyan-soft);
  color: #7dd3fc;
}

.faq-list details[open] summary::after {
  content: "-";
}

.faq-list details p {
  padding: 0 18px 18px;
}

.site-footer {
  padding: 26px 0 96px;
  border-top: 1px solid var(--line);
  background:
    linear-gradient(105deg, #0f172a 0%, #24153d 28%, #581c87 52%, #8f123d 74%, #ef4444 100%),
    linear-gradient(180deg, #0b1120, #0f172a);
}

.friend-links {
  padding: 0 0 24px;
  margin-bottom: 18px;
  text-align: center;
}

.friend-links h2 {
  margin-bottom: 18px;
  font-size: 30px;
  font-weight: 900;
  text-shadow: 0 3px 18px rgba(2, 6, 23, 0.45);
}

.friend-link-grid {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 14px;
}

.friend-link-grid a {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 8px 30px;
  border: 1px solid rgba(226, 232, 240, 0.26);
  border-radius: 999px;
  color: #f8fafc;
  background:
    linear-gradient(180deg, rgba(226, 232, 240, 0.16), rgba(226, 232, 240, 0.07)),
    rgba(15, 23, 42, 0.28);
  box-shadow:
    inset 0 1px 0 rgba(255, 255, 255, 0.18),
    0 10px 26px rgba(2, 6, 23, 0.24);
  font-weight: 800;
  text-align: center;
  white-space: nowrap;
}

.friend-link-grid a:hover {
  border-color: rgba(226, 232, 240, 0.48);
  background:
    linear-gradient(180deg, rgba(226, 232, 240, 0.24), rgba(226, 232, 240, 0.1)),
    rgba(15, 23, 42, 0.34);
  transform: translateY(-1px);
}

.floating-detail {
  position: fixed;
  right: 22px;
  bottom: 22px;
  z-index: 90;
  min-width: 128px;
  min-height: 52px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 13px 18px;
  border: 1px solid rgba(255, 255, 255, 0.22);
  border-radius: 999px;
  color: #fff;
  background: linear-gradient(135deg, var(--alert), var(--violet));
  box-shadow: 0 18px 48px rgba(239, 68, 68, 0.35), 0 0 0 1px rgba(14, 165, 233, 0.16);
  font-weight: 900;
}

.floating-detail:hover {
  transform: translateY(-2px);
  border-color: rgba(255, 255, 255, 0.38);
  box-shadow: 0 24px 58px rgba(239, 68, 68, 0.42), 0 0 28px rgba(112, 26, 117, 0.36);
  filter: saturate(1.12) brightness(1.05);
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  color: var(--muted);
  font-size: 14px;
}

.footer-inner p {
  margin: 0;
}

@media (max-width: 980px) {
  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: absolute;
    top: 72px;
    left: 20px;
    right: 20px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: 12px;
    border: 1px solid var(--line);
    border-radius: 8px;
    background: rgba(11, 17, 32, 0.98);
    box-shadow: var(--shadow);
  }

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

  .site-nav a {
    justify-content: flex-start;
  }

  .site-nav .nav-cta {
    margin-left: 0;
    justify-content: center;
  }

  h1 {
    font-size: 40px;
  }

  .hero {
    min-height: 88svh;
  }

  .hero-inner {
    padding-top: 108px;
  }

  .hero-facts,
  .signal-grid,
  .topic-grid,
  .guide-grid,
  .feature-list,
  .section-split,
  .section-split.reverse {
    grid-template-columns: 1fr;
  }

  .section {
    padding: 72px 0;
  }

  .timeline li {
    grid-template-columns: 1fr;
    gap: 8px;
  }
}

@media (max-width: 640px) {
  .container {
    width: min(100% - 28px, var(--container));
  }

  .site-header {
    padding-inline: 14px;
  }

  .brand span {
    max-width: 148px;
  }

  h1 {
    font-size: 34px;
  }

  .hero-lead {
    font-size: 16px;
  }

  .hero-actions {
    align-items: stretch;
    flex-direction: column;
  }

  .btn {
    width: 100%;
  }

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

  .section-head h2,
  .section-copy h2 {
    font-size: 28px;
  }

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

  .gallery-thumbs {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 8px;
  }

  .footer-inner {
    display: grid;
  }

  .friend-link-grid {
    display: grid;
    grid-template-columns: 1fr;
  }

  .friend-links h2 {
    font-size: 26px;
  }

  .friend-link-grid a {
    min-height: 46px;
    white-space: normal;
  }

  .floating-detail {
    left: 14px;
    right: 14px;
    bottom: 14px;
    width: auto;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.001ms !important;
    animation-duration: 0.001ms !important;
  }
}