:root {
  --ink: #171a21;
  --ink-soft: #333843;
  --paper: #fffdf4;
  --white: #ffffff;
  --yellow: #ffd633;
  --yellow-deep: #efb900;
  --teal: #16a99c;
  --teal-soft: #dff7f3;
  --coral: #ff6f61;
  --line: #dedbd0;
  --muted: #6a6e76;
  --shadow: 0 14px 38px rgba(23, 26, 33, 0.1);
  --max-width: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  line-height: 1.7;
}

body.menu-open {
  overflow: hidden;
}

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

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

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

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 1000;
  padding: 8px 12px;
  color: var(--white);
  background: var(--ink);
  transform: translateY(-150%);
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid rgba(23, 26, 33, 0.1);
  background: rgba(255, 253, 244, 0.96);
  backdrop-filter: blur(14px);
}

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

.nav-wrap {
  min-height: 76px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 11px;
  font-size: 20px;
  font-weight: 900;
  white-space: nowrap;
}

.brand img {
  width: 44px;
  height: 44px;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 26px;
}

.main-nav > a:not(.download-button) {
  position: relative;
  padding: 24px 0;
  font-size: 15px;
  font-weight: 700;
}

.main-nav > a:not(.download-button)::after {
  position: absolute;
  right: 0;
  bottom: 17px;
  left: 0;
  height: 3px;
  border-radius: 3px;
  background: var(--teal);
  content: "";
  transform: scaleX(0);
  transition: transform 180ms ease;
}

.main-nav > a:hover::after,
.main-nav > a[aria-current="page"]::after {
  transform: scaleX(1);
}

.menu-button {
  display: none;
  width: 44px;
  height: 44px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  color: var(--ink);
  background: transparent;
  font-size: 24px;
  line-height: 1;
  cursor: pointer;
}

.download-button {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  padding: 11px 24px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  color: var(--ink);
  background: var(--yellow);
  box-shadow: 4px 4px 0 var(--ink);
  font-weight: 900;
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.download-button:hover {
  background: #ffe574;
  box-shadow: 2px 2px 0 var(--ink);
  transform: translate(2px, 2px);
}

.download-button:focus-visible,
.menu-button:focus-visible,
.main-nav a:focus-visible,
.text-link:focus-visible,
summary:focus-visible {
  outline: 3px solid var(--teal);
  outline-offset: 3px;
}

.hero {
  overflow: hidden;
  border-bottom: 1px solid var(--line);
  background: var(--yellow);
}

.hero-grid {
  min-height: 670px;
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(360px, 0.95fr);
  align-items: center;
  gap: 56px;
  padding: 70px 0 54px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 18px;
  padding: 5px 10px;
  border: 1px solid var(--ink);
  border-radius: 4px;
  background: var(--white);
  font-size: 13px;
  font-weight: 900;
}

.hero h1,
.page-hero h1 {
  max-width: 720px;
  margin: 0;
  font-size: 68px;
  line-height: 1.06;
  letter-spacing: 0;
}

.hero h1 {
  white-space: nowrap;
}

.hero-copy > p {
  max-width: 640px;
  margin: 24px 0 0;
  color: var(--ink-soft);
  font-size: 19px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 18px;
  margin-top: 34px;
}

.hero-actions .download-button {
  min-width: 150px;
  min-height: 54px;
}

.text-link {
  border-bottom: 2px solid var(--ink);
  font-weight: 900;
}

.hero-note {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 22px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  font-size: 14px;
  font-weight: 700;
}

.hero-note li::before {
  margin-right: 7px;
  color: var(--teal);
  content: "●";
}

.hero-visual {
  position: relative;
  height: 545px;
}

.phone-frame {
  position: absolute;
  top: 0;
  left: 50%;
  width: min(290px, 70vw);
  padding: 9px;
  border: 3px solid var(--ink);
  border-radius: 30px;
  background: var(--ink);
  box-shadow: var(--shadow);
  transform: translateX(-50%) rotate(2deg);
}

.phone-frame img {
  width: 100%;
  max-width: 400px;
  height: auto;
  border-radius: 20px;
}

.visual-tag {
  position: absolute;
  z-index: 2;
  max-width: 180px;
  padding: 13px 16px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  background: var(--white);
  box-shadow: 4px 4px 0 var(--ink);
  font-size: 14px;
  font-weight: 900;
}

.visual-tag.tag-one {
  top: 76px;
  right: -4px;
}

.visual-tag.tag-two {
  bottom: 52px;
  left: -8px;
  background: var(--teal-soft);
}

.stat-strip {
  border-bottom: 1px solid var(--line);
  background: var(--white);
}

.stats {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
}

.stat {
  padding: 24px 20px;
  border-right: 1px solid var(--line);
  text-align: center;
}

.stat:first-child {
  border-left: 1px solid var(--line);
}

.stat strong,
.stat span {
  display: block;
}

.stat strong {
  font-size: 20px;
}

.stat span {
  color: var(--muted);
  font-size: 13px;
}

.content-section {
  padding: 88px 0;
}

.content-section.alt {
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--white);
}

.section-heading {
  margin: 0 0 36px;
  font-size: 42px;
  line-height: 1.16;
  letter-spacing: 0;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.feature-card,
.route-card,
.quote-card,
.info-card {
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--white);
}

.feature-card {
  min-height: 250px;
  padding: 26px;
  border-top: 5px solid var(--yellow);
}

.feature-card:nth-child(2) {
  border-top-color: var(--teal);
}

.feature-card:nth-child(3) {
  border-top-color: var(--coral);
}

.feature-card:nth-child(4) {
  border-top-color: var(--ink);
}

.feature-index {
  color: var(--teal);
  font-size: 14px;
  font-weight: 900;
}

.feature-card h3,
.route-card h3,
.info-card h3 {
  margin: 16px 0 10px;
  font-size: 21px;
  line-height: 1.3;
}

.feature-card p,
.route-card p,
.info-card p,
.quote-card blockquote {
  margin: 0;
  color: var(--muted);
}

.screen-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 22px;
}

.screen-item {
  margin: 0;
}

.screen-item img {
  width: 100%;
  max-width: 390px;
  height: auto;
  border: 2px solid var(--ink);
  border-radius: 8px;
  background: var(--yellow);
  box-shadow: 7px 7px 0 rgba(23, 26, 33, 0.12);
}

.screen-item figcaption {
  padding: 15px 2px 0;
  font-size: 14px;
  font-weight: 800;
}

.topic-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 52px;
  align-items: start;
}

.topic-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  overflow: hidden;
  border: 1px solid var(--ink);
  border-radius: 8px;
  background: var(--ink);
}

.topic-item {
  min-height: 124px;
  padding: 24px;
  background: var(--white);
}

.topic-item strong {
  display: block;
  margin-bottom: 7px;
}

.topic-item span {
  color: var(--muted);
  font-size: 14px;
}

.topic-aside {
  padding: 32px;
  border: 2px solid var(--ink);
  border-radius: 8px;
  background: var(--teal-soft);
  box-shadow: 8px 8px 0 var(--ink);
}

.topic-aside h3 {
  margin: 0 0 12px;
  font-size: 26px;
}

.topic-aside ul {
  margin: 20px 0 26px;
  padding-left: 20px;
}

.route-grid,
.quote-grid,
.info-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
}

.route-card,
.info-card {
  padding: 30px;
}

.route-label {
  color: var(--coral);
  font-size: 13px;
  font-weight: 900;
}

.route-card .text-link {
  display: inline-block;
  margin-top: 22px;
}

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

.quote-card {
  padding: 28px;
}

.quote-card blockquote {
  font-size: 16px;
}

.quote-card cite {
  display: block;
  margin-top: 18px;
  color: var(--ink);
  font-size: 13px;
  font-style: normal;
  font-weight: 900;
}

.faq-preview,
.faq-list {
  border-top: 2px solid var(--ink);
}

details {
  border-bottom: 1px solid var(--line);
  background: var(--white);
}

summary {
  display: flex;
  min-height: 68px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px 6px;
  font-weight: 900;
  cursor: pointer;
  list-style: none;
}

summary::-webkit-details-marker {
  display: none;
}

summary::after {
  flex: 0 0 auto;
  color: var(--teal);
  font-size: 24px;
  content: "+";
}

details[open] summary::after {
  content: "−";
}

.answer {
  max-width: 900px;
  padding: 0 42px 22px 6px;
  color: var(--muted);
}

.answer p {
  margin: 0 0 12px;
}

.answer p:last-child {
  margin-bottom: 0;
}

.cta-band {
  padding: 72px 0;
  border-top: 2px solid var(--ink);
  background: var(--yellow);
}

.cta-layout {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
}

.cta-layout h2 {
  margin: 0;
  font-size: 46px;
  line-height: 1.1;
}

.cta-layout .download-button {
  flex: 0 0 auto;
  min-width: 160px;
  min-height: 54px;
  background: var(--white);
}

.site-footer {
  color: #d8dbe1;
  background: var(--ink);
}

.footer-main {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr 1fr;
  gap: 50px;
  padding: 54px 0 38px;
}

.footer-brand {
  color: var(--white);
}

.footer-brand img {
  border: 1px solid #4b4f59;
}

.footer-main h2 {
  margin: 0 0 15px;
  color: var(--white);
  font-size: 16px;
}

.footer-main p {
  max-width: 410px;
  margin: 18px 0 0;
  color: #aeb2bb;
  font-size: 14px;
}

.footer-links {
  display: grid;
  gap: 9px;
  font-size: 14px;
}

.footer-links a:hover {
  color: var(--yellow);
}

.disclaimer {
  padding: 20px 0 30px;
  border-top: 1px solid #343842;
  color: #9398a3;
  font-size: 12px;
}

.page-hero {
  border-bottom: 1px solid var(--line);
  background: var(--yellow);
}

.page-hero .section-inner {
  padding: 74px 0 66px;
}

.page-hero h1 {
  font-size: 58px;
}

.page-hero .lead {
  max-width: 760px;
  margin: 22px 0 0;
  color: var(--ink-soft);
  font-size: 18px;
}

.breadcrumbs {
  margin-bottom: 22px;
  font-size: 13px;
  font-weight: 800;
}

.breadcrumbs span {
  margin: 0 7px;
  color: var(--muted);
}

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 60px;
  align-items: start;
}

.article-body h2 {
  margin: 58px 0 24px;
  font-size: 32px;
  line-height: 1.2;
}

.article-body h2:first-child {
  margin-top: 0;
}

.article-body h3 {
  margin: 0 0 10px;
  font-size: 20px;
}

.article-body p {
  margin: 0 0 18px;
  color: var(--ink-soft);
}

.article-body ul,
.article-body ol {
  color: var(--ink-soft);
}

.step-list {
  display: grid;
  gap: 16px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.step {
  display: grid;
  grid-template-columns: 58px minmax(0, 1fr);
  gap: 20px;
  padding: 25px 0;
  border-bottom: 1px solid var(--line);
}

.step-number {
  display: grid;
  width: 54px;
  height: 54px;
  place-items: center;
  border: 2px solid var(--ink);
  border-radius: 8px;
  background: var(--yellow);
  font-size: 21px;
  font-weight: 900;
}

.step p {
  margin-bottom: 0;
}

.notice {
  margin: 28px 0;
  padding: 24px;
  border-left: 6px solid var(--teal);
  background: var(--teal-soft);
}

.notice strong {
  display: block;
  margin-bottom: 6px;
}

.article-aside {
  position: sticky;
  top: 104px;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--white);
}

.article-aside h2 {
  margin: 0 0 16px;
  font-size: 16px;
}

.article-aside nav {
  display: grid;
  gap: 10px;
  margin-bottom: 24px;
}

.article-aside nav a {
  color: var(--muted);
  font-size: 14px;
}

.article-aside nav a:hover {
  color: var(--teal);
}

.function-row {
  display: grid;
  grid-template-columns: 170px minmax(0, 1fr);
  gap: 28px;
  padding: 28px 0;
  border-bottom: 1px solid var(--line);
}

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

.function-row h3 {
  margin: 0;
}

.function-row p {
  margin: 0;
}

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

.check-list li {
  position: relative;
  padding-left: 30px;
}

.check-list li::before {
  position: absolute;
  top: 2px;
  left: 0;
  color: var(--teal);
  font-weight: 900;
  content: "✓";
}

@media (max-width: 980px) {
  .menu-button {
    display: inline-grid;
    place-items: center;
  }

  .main-nav {
    position: fixed;
    top: 76px;
    right: 0;
    left: 0;
    display: none;
    padding: 20px;
    border-bottom: 2px solid var(--ink);
    background: var(--paper);
  }

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

  .main-nav > a:not(.download-button) {
    padding: 9px 2px;
  }

  .main-nav > a:not(.download-button)::after {
    bottom: 4px;
  }

  .hero-grid {
    grid-template-columns: 1fr 360px;
    gap: 24px;
  }

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

  .topic-grid,
  .article-layout {
    grid-template-columns: 1fr;
  }

  .article-aside {
    position: static;
  }
}

@media (max-width: 720px) {
  .nav-wrap,
  .section-inner,
  .footer-inner {
    width: min(calc(100% - 28px), var(--max-width));
  }

  .nav-wrap {
    min-height: 68px;
  }

  .main-nav {
    top: 68px;
  }

  .brand {
    font-size: 18px;
  }

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

  .hero-grid {
    min-height: auto;
    grid-template-columns: 1fr;
    padding: 54px 0 36px;
  }

  .hero h1,
  .page-hero h1 {
    font-size: 36px;
  }

  .section-heading {
    font-size: 32px;
  }

  .cta-layout h2 {
    font-size: 34px;
  }

  .hero-copy > p,
  .page-hero .lead {
    font-size: 16px;
  }

  .hero-visual {
    height: 440px;
    margin-top: 20px;
  }

  .phone-frame {
    width: 224px;
  }

  .visual-tag {
    max-width: 145px;
    padding: 10px 12px;
    font-size: 12px;
  }

  .visual-tag.tag-one {
    right: 0;
  }

  .visual-tag.tag-two {
    bottom: 28px;
    left: 0;
  }

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

  .stat:nth-child(3) {
    border-left: 1px solid var(--line);
  }

  .stat:nth-child(-n + 2) {
    border-bottom: 1px solid var(--line);
  }

  .content-section {
    padding: 62px 0;
  }

  .feature-grid,
  .screen-grid,
  .topic-list,
  .route-grid,
  .quote-grid,
  .info-grid {
    grid-template-columns: 1fr;
  }

  .screen-item {
    width: min(100%, 340px);
    margin: 0 auto;
  }

  .topic-grid {
    gap: 32px;
  }

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

  .footer-main {
    grid-template-columns: 1fr;
    gap: 30px;
  }

  .page-hero .section-inner {
    padding: 50px 0 46px;
  }

  .article-layout {
    gap: 36px;
  }

  .function-row {
    grid-template-columns: 1fr;
    gap: 8px;
  }
}

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

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
  }
}