:root {
  --ink: #17262c;
  --muted: #60727a;
  --line: #d8e0df;
  --paper: #f7f4ee;
  --surface: #ffffff;
  --soft: #edf5f1;
  --teal: #2d6f73;
  --teal-dark: #1f4f55;
  --coral: #d86a55;
  --coral-dark: #a84a3b;
  --amber: #d19c4a;
  --shadow: 0 18px 50px rgba(23, 38, 44, .14);
  --radius: 8px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  text-size-adjust: 100%;
}

body {
  margin: 0;
  font-family: "Microsoft YaHei", "PingFang SC", "Noto Sans CJK SC", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.72;
}

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

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

p,
h1,
h2,
h3,
h4 {
  margin-top: 0;
}

p {
  color: var(--muted);
}

strong {
  color: var(--teal-dark);
  font-weight: 900;
}

.hero strong,
.final-cta strong {
  color: #ffd9bd;
}

.system-card strong,
.guide-main strong,
.check-panel strong,
.faq-list strong {
  color: var(--coral-dark);
}

.copy-block strong,
.section-heading strong {
  padding: 0 2px;
  color: var(--teal-dark);
  background: linear-gradient(180deg, transparent 62%, rgba(216, 106, 85, .18) 0);
}

.skip-link {
  position: absolute;
  left: 12px;
  top: -48px;
  z-index: 1000;
  padding: 10px 14px;
  background: var(--ink);
  color: #fff;
  border-radius: var(--radius);
}

.skip-link:focus {
  top: 12px;
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(247, 244, 238, .9);
  border-bottom: 1px solid rgba(216, 224, 223, .8);
  backdrop-filter: blur(16px);
}

.nav-shell {
  width: min(var(--max), calc(100% - 32px));
  min-height: 72px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
}

.brand,
.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  color: var(--ink);
}

.brand img,
.footer-brand img {
  border-radius: 50%;
  border: 2px solid rgba(45, 111, 115, .2);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 18px;
  font-size: 14px;
  color: #34494f;
}

.nav-links a {
  padding: 8px 2px;
  border-bottom: 2px solid transparent;
  transition: color .2s ease, border-color .2s ease, transform .2s ease;
}

.nav-links a:hover,
.nav-links a.is-active {
  color: var(--teal-dark);
  border-color: var(--coral);
}

.nav-links a:hover {
  transform: translateY(-1px);
}

.nav-links .nav-cta {
  padding: 9px 16px;
  color: #fff;
  border: 0;
  border-radius: var(--radius);
  background: var(--teal-dark);
  box-shadow: 0 10px 24px rgba(31, 79, 85, .18);
}

.nav-links .nav-cta:hover {
  color: #fff;
  background: var(--coral-dark);
  box-shadow: 0 14px 30px rgba(168, 74, 59, .24);
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 10px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.nav-toggle span {
  display: block;
  height: 2px;
  margin: 5px 0;
  background: var(--ink);
  transform-origin: center;
  transition: opacity .2s ease, transform .2s ease;
}

.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: 86vh;
  overflow: hidden;
  color: #fff;
  background: #17262c;
}

.hero-media,
.hero-overlay {
  position: absolute;
  inset: 0;
}

.hero-media {
  background-image: url("img/tu1.png");
  background-position: center;
  background-size: cover;
  transform: scale(1.03);
}

.hero-overlay {
  background:
    linear-gradient(90deg, rgba(16, 31, 37, .92) 0%, rgba(16, 31, 37, .72) 42%, rgba(16, 31, 37, .24) 100%),
    linear-gradient(0deg, rgba(23, 38, 44, .8), rgba(23, 38, 44, .12) 42%);
}

.hero-layout {
  position: relative;
  min-height: 86vh;
  display: grid;
  grid-template-columns: minmax(0, 1fr) 350px;
  align-items: center;
  gap: 48px;
  padding: 120px 0 88px;
}

.eyebrow,
.section-kicker {
  display: inline-flex;
  align-items: center;
  margin-bottom: 14px;
  font-size: 13px;
  font-weight: 800;
  color: var(--coral);
  text-transform: uppercase;
}

.hero .eyebrow {
  color: #ffd9bd;
}

.hero h1 {
  max-width: 780px;
  margin-bottom: 20px;
  font-size: clamp(34px, 5.4vw, 68px);
  line-height: 1.04;
  letter-spacing: 0;
  color: #fff4e8;
  text-shadow: 0 10px 30px rgba(0, 0, 0, .34);
}

.hero-subtitle {
  max-width: 690px;
  margin-bottom: 30px;
  color: rgba(255, 255, 255, .86);
  font-size: 19px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}

.button {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  padding: 12px 22px;
  border-radius: var(--radius);
  border: 1px solid transparent;
  font-weight: 800;
  position: relative;
  overflow: hidden;
  transition: transform .2s ease, background .2s ease, border-color .2s ease, box-shadow .2s ease;
}

.button::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(120deg, transparent, rgba(255, 255, 255, .32), transparent);
  transform: translateX(-120%);
  transition: transform .55s ease;
}

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

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

.button-primary {
  color: #fff;
  background: var(--coral);
  box-shadow: 0 12px 28px rgba(216, 106, 85, .28);
}

.button-primary:hover {
  background: var(--coral-dark);
  box-shadow: 0 18px 34px rgba(168, 74, 59, .32);
}

.button-ghost {
  color: #fff;
  border-color: rgba(255, 255, 255, .5);
  background: rgba(255, 255, 255, .08);
}

.button-ghost:hover {
  border-color: rgba(255, 255, 255, .82);
  background: rgba(255, 255, 255, .14);
}

.hero-panel {
  padding: 22px;
  border: 1px solid rgba(255, 255, 255, .24);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, .12);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
  transition: transform .24s ease, border-color .24s ease, background .24s ease;
}

.hero-panel:hover {
  transform: translateY(-4px);
  border-color: rgba(255, 217, 189, .6);
  background: rgba(255, 255, 255, .16);
}

.hero-panel dl {
  margin: 0;
  display: grid;
  gap: 16px;
}

.hero-panel div {
  padding-bottom: 14px;
  border-bottom: 1px solid rgba(255, 255, 255, .18);
}

.hero-panel div:last-child {
  padding-bottom: 0;
  border-bottom: 0;
}

.hero-panel dt {
  margin-bottom: 4px;
  color: #ffd9bd;
  font-size: 13px;
  font-weight: 800;
}

.hero-panel dd {
  margin: 0;
  color: rgba(255, 255, 255, .9);
}

.quick-strip {
  border-bottom: 1px solid var(--line);
  background: #fff;
}

.keyword-row {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 10px;
  padding: 18px 0;
}

.keyword-row span {
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--soft);
  color: var(--teal-dark);
  font-size: 14px;
  font-weight: 700;
  transition: transform .2s ease, background .2s ease, border-color .2s ease;
}

.keyword-row span:hover {
  transform: translateY(-2px);
  border-color: rgba(45, 111, 115, .35);
  background: #fff;
}

.section {
  padding: 90px 0;
}

.split-layout {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(320px, .95fr);
  gap: 48px;
  align-items: center;
}

.section-heading {
  max-width: 820px;
  margin-bottom: 34px;
}

.section-heading h2,
.copy-block h2,
.final-cta h2 {
  margin-bottom: 16px;
  font-size: clamp(24px, 3.1vw, 36px);
  line-height: 1.18;
  letter-spacing: 0;
  color: var(--teal-dark);
}

.final-cta h2 {
  color: #fff4e8;
}

.copy-block p,
.section-heading p {
  font-size: 17px;
}

.check-list {
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 10px;
}

.check-list li {
  position: relative;
  padding-left: 28px;
  color: #42585f;
}

.check-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: .65em;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--teal);
  box-shadow: inset 0 0 0 3px #fff;
}

.feature-figure,
.wide-media figure,
.guide-aside figure {
  margin: 0;
  overflow: hidden;
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
  transition: transform .24s ease, box-shadow .24s ease;
}

.feature-figure img,
.wide-media img,
.guide-aside img {
  width: 100%;
  object-fit: cover;
  transition: transform .5s ease, filter .24s ease;
}

.feature-figure:hover,
.wide-media figure:hover,
.guide-aside figure:hover {
  transform: translateY(-4px);
  box-shadow: 0 24px 58px rgba(23, 38, 44, .18);
}

.feature-figure:hover img,
.wide-media figure:hover img,
.guide-aside figure:hover img {
  transform: scale(1.035);
  filter: saturate(1.05);
}

.feature-figure img {
  aspect-ratio: 460 / 215;
}

figcaption {
  padding: 12px 14px 14px;
  color: #5f7178;
  font-size: 14px;
  background: #fff;
}

.systems-section {
  background: #fff;
}

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

.system-card {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, #fff, #f6faf8);
  transition: transform .22s ease, box-shadow .22s ease, border-color .22s ease, background .22s ease;
}

.system-card:hover {
  transform: translateY(-5px);
  border-color: rgba(45, 111, 115, .35);
  background: linear-gradient(180deg, #fff, #edf6f2);
  box-shadow: 0 18px 42px rgba(23, 38, 44, .12);
}

.card-icon {
  display: inline-flex;
  margin-bottom: 18px;
  color: var(--coral);
  font-weight: 900;
  transition: color .2s ease, transform .2s ease;
}

.system-card:hover .card-icon {
  color: var(--teal-dark);
  transform: translateX(2px);
}

.system-card h3 {
  margin-bottom: 10px;
  font-size: 20px;
}

.system-card p {
  margin-bottom: 0;
}

.wide-media {
  margin-top: 34px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.wide-media img {
  aspect-ratio: 16 / 9;
}

.guide-section {
  background: linear-gradient(180deg, var(--paper), #eef5f2);
}

.guide-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 360px;
  gap: 24px;
  align-items: start;
}

.guide-main,
.guide-aside,
.check-panel,
.faq-list details,
.timeline-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  box-shadow: 0 12px 36px rgba(23, 38, 44, .08);
  transition: transform .22s ease, box-shadow .22s ease, border-color .22s ease;
}

.guide-main:hover,
.guide-aside:hover,
.check-panel:hover,
.timeline-item:hover {
  transform: translateY(-4px);
  border-color: rgba(45, 111, 115, .32);
  box-shadow: 0 20px 48px rgba(23, 38, 44, .13);
}

.guide-main,
.guide-aside,
.check-panel {
  padding: 28px;
}

.guide-main h3,
.guide-aside h3,
.check-panel h3 {
  font-size: 24px;
  margin-bottom: 16px;
}

.number-list,
.compact-checks {
  margin: 0 0 30px;
  padding-left: 22px;
  color: #3f555c;
}

.number-list li,
.compact-checks li {
  margin-bottom: 10px;
}

.route-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.route-grid div {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--soft);
  transition: transform .2s ease, background .2s ease, border-color .2s ease;
}

.route-grid div:hover {
  transform: translateY(-3px);
  border-color: rgba(216, 106, 85, .35);
  background: #fff;
}

.route-grid h4 {
  margin-bottom: 8px;
  color: var(--teal-dark);
}

.route-grid p {
  margin-bottom: 0;
  font-size: 15px;
}

.priority-list {
  display: grid;
  gap: 12px;
  margin-bottom: 20px;
}

.priority-list div {
  display: grid;
  gap: 6px;
  padding: 14px;
  border-left: 4px solid var(--coral);
  background: var(--soft);
  transition: transform .2s ease, background .2s ease, border-color .2s ease;
}

.priority-list div:hover {
  transform: translateX(3px);
  border-left-color: var(--teal);
  background: #fff;
}

.priority-list strong {
  color: var(--ink);
}

.priority-list span {
  color: var(--muted);
}

.guide-aside figure {
  box-shadow: none;
  border: 1px solid var(--line);
}

.check-panel {
  margin-top: 24px;
}

.compact-checks {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px 26px;
  margin-bottom: 0;
}

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

.timeline {
  position: relative;
  display: grid;
  gap: 16px;
}

.timeline-item {
  position: relative;
  padding: 24px 24px 24px 30px;
  border-left: 5px solid var(--teal);
}

.timeline-item:hover {
  border-left-color: var(--coral);
}

.timeline-item time {
  display: inline-flex;
  margin-bottom: 8px;
  color: var(--coral-dark);
  font-weight: 900;
}

.timeline-item h3 {
  margin-bottom: 8px;
  font-size: 21px;
}

.timeline-item p {
  margin-bottom: 0;
}

.faq-section {
  background: #fff;
}

.faq-layout {
  display: grid;
  grid-template-columns: .85fr 1.15fr;
  gap: 34px;
  align-items: start;
}

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

.faq-list details {
  padding: 0;
}

.faq-list details:hover {
  border-color: rgba(45, 111, 115, .32);
  box-shadow: 0 18px 42px rgba(23, 38, 44, .12);
}

.faq-list summary {
  cursor: pointer;
  padding: 18px 20px;
  font-weight: 800;
  list-style: none;
  transition: color .2s ease, background .2s ease;
}

.faq-list summary:hover {
  color: var(--teal-dark);
  background: var(--soft);
}

.faq-list summary::-webkit-details-marker {
  display: none;
}

.faq-list summary::after {
  content: "+";
  float: right;
  color: var(--coral);
  font-size: 22px;
  line-height: 1;
}

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

.faq-list details p {
  margin: 0;
  padding: 0 20px 20px;
}

.final-cta {
  padding: 70px 0;
  background: var(--teal-dark);
  color: #fff;
}

.final-cta p {
  color: rgba(255, 255, 255, .82);
}

.final-cta .section-kicker {
  color: #ffd9bd;
}

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

.cta-layout h2 {
  margin-bottom: 10px;
}

.cta-layout p {
  margin-bottom: 0;
}

.site-footer {
  padding: 40px 0;
  border-top: 1px solid var(--line);
  background: #14252a;
  color: #fff;
}

.site-footer p {
  max-width: 600px;
  margin: 14px 0 0;
  color: rgba(255, 255, 255, .72);
}

.footer-layout {
  display: flex;
  justify-content: space-between;
  gap: 28px;
}

.footer-brand {
  color: #fff;
}

.site-footer nav {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 18px;
  justify-content: flex-end;
  align-content: flex-start;
}

.site-footer nav a {
  color: rgba(255, 255, 255, .76);
}

.site-footer nav a:hover {
  color: #fff;
}

.reveal {
  opacity: 0;
  transform: translateY(18px);
  transition: opacity .55s ease, transform .55s ease;
}

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

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

  *,
  *::before,
  *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
  }
}

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

  .nav-links {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 72px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 12px;
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: #fff;
    box-shadow: var(--shadow);
  }

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

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

  .nav-links .nav-cta {
    margin-top: 6px;
    text-align: center;
  }

  .hero-layout,
  .split-layout,
  .guide-layout,
  .faq-layout {
    grid-template-columns: 1fr;
  }

  .hero-layout {
    align-items: end;
    gap: 26px;
    padding-top: 104px;
  }

  .hero-panel {
    max-width: 560px;
  }

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

  .cta-layout,
  .footer-layout {
    align-items: flex-start;
    flex-direction: column;
  }

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

@media (max-width: 680px) {
  .section-inner {
    width: min(100% - 28px, var(--max));
  }

  .nav-shell {
    width: min(100% - 24px, var(--max));
  }

  .brand span {
    max-width: 168px;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .hero,
  .hero-layout {
    min-height: 82vh;
  }

  .hero h1 {
    font-size: 34px;
  }

  .hero-subtitle {
    font-size: 17px;
  }

  .hero-actions,
  .button {
    width: 100%;
  }

  .section {
    padding: 66px 0;
  }

  .system-grid,
  .wide-media,
  .route-grid,
  .compact-checks {
    grid-template-columns: 1fr;
  }

  .guide-main,
  .guide-aside,
  .check-panel {
    padding: 22px;
  }

  .keyword-row {
    justify-content: flex-start;
    overflow-x: auto;
    flex-wrap: nowrap;
    padding-bottom: 16px;
  }

  .keyword-row span {
    white-space: nowrap;
  }
}