:root {
  --ink: #17171f;
  --paper: #fffdf8;
  --paper-deep: #f4f0e7;
  --coral: #ff5b45;
  --coral-dark: #d93b2b;
  --teal: #20b8a6;
  --teal-dark: #087f75;
  --yellow: #ffd84d;
  --muted: #686872;
  --line: #d9d5cd;
  --white: #ffffff;
  --shadow: 8px 8px 0 var(--ink);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "微软雅黑", Arial, Helvetica, sans-serif;
  line-height: 1.72;
}

body.menu-open {
  overflow: hidden;
}

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

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

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

button {
  font: inherit;
}

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 100;
  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: 50;
  border-bottom: 2px solid var(--ink);
  background: rgba(255, 253, 248, 0.96);
  backdrop-filter: blur(12px);
}

.nav-shell {
  width: min(1180px, calc(100% - 40px));
  min-height: 74px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 22px;
  font-weight: 900;
}

.brand img {
  width: 42px;
  height: 42px;
  border: 2px solid var(--ink);
  border-radius: 6px;
}

.brand-word {
  letter-spacing: 0;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.site-nav > a:not(.download-button) {
  min-height: 42px;
  padding: 8px 13px;
  display: inline-flex;
  align-items: center;
  border-bottom: 3px solid transparent;
  font-size: 15px;
  font-weight: 700;
}

.site-nav > a[aria-current="page"],
.site-nav > a:not(.download-button):hover {
  border-bottom-color: var(--coral);
}

.menu-toggle {
  width: 44px;
  height: 44px;
  display: none;
  align-items: center;
  justify-content: center;
  border: 2px solid var(--ink);
  border-radius: 6px;
  color: var(--ink);
  background: var(--white);
  cursor: pointer;
}

.menu-toggle span,
.menu-toggle::before,
.menu-toggle::after {
  width: 20px;
  height: 2px;
  content: "";
  display: block;
  background: currentColor;
  transition: transform 180ms ease, opacity 180ms ease;
}

.menu-toggle span {
  margin: 4px 0;
}

.menu-toggle[aria-expanded="true"] span {
  opacity: 0;
}

.menu-toggle[aria-expanded="true"]::before {
  transform: translateY(6px) rotate(45deg);
}

.menu-toggle[aria-expanded="true"]::after {
  transform: translateY(-6px) rotate(-45deg);
}

.download-button {
  min-height: 46px;
  padding: 10px 18px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  color: var(--white);
  background: var(--coral);
  box-shadow: 4px 4px 0 var(--ink);
  font-weight: 900;
  cursor: pointer;
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.download-button::before {
  content: "↓";
  font-size: 18px;
  line-height: 1;
}

.download-button:hover {
  color: var(--white);
  background: var(--coral-dark);
  box-shadow: 2px 2px 0 var(--ink);
  transform: translate(2px, 2px);
}

.download-button:focus-visible,
.menu-toggle:focus-visible,
.faq-question:focus-visible,
a:focus-visible {
  outline: 3px solid var(--teal);
  outline-offset: 3px;
}

.download-button.light {
  color: var(--ink);
  background: var(--yellow);
}

.section-shell {
  width: min(1180px, calc(100% - 40px));
  margin: 0 auto;
}

.hero {
  position: relative;
  min-height: 690px;
  overflow: hidden;
  border-bottom: 2px solid var(--ink);
  background-color: var(--paper);
  background-image: linear-gradient(rgba(23, 23, 31, 0.06) 1px, transparent 1px), linear-gradient(90deg, rgba(23, 23, 31, 0.06) 1px, transparent 1px);
  background-size: 28px 28px;
}

.hero::before {
  position: absolute;
  top: 0;
  right: 0;
  width: 38%;
  height: 100%;
  content: "";
  background: var(--teal);
  border-left: 2px solid var(--ink);
}

.hero-shell {
  position: relative;
  z-index: 2;
  width: min(1180px, calc(100% - 40px));
  min-height: 690px;
  margin: 0 auto;
  padding: 70px 0 58px;
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(360px, 0.95fr);
  align-items: center;
  gap: 70px;
}

.eyebrow {
  width: fit-content;
  margin: 0 0 20px;
  padding: 5px 10px;
  border: 2px solid var(--ink);
  color: var(--ink);
  background: var(--yellow);
  box-shadow: 3px 3px 0 var(--ink);
  font-size: 13px;
  font-weight: 900;
}

.hero h1,
.page-hero h1 {
  max-width: 760px;
  margin: 0;
  line-height: 1.02;
  letter-spacing: 0;
}

.hero h1 {
  font-size: clamp(48px, 6vw, 78px);
}

.hero-copy > p:first-of-type {
  max-width: 660px;
  margin: 26px 0 0;
  color: #3f3f48;
  font-size: 19px;
  line-height: 1.85;
}

.hero-actions {
  margin-top: 28px;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 14px;
}

.text-link {
  padding: 9px 3px;
  border-bottom: 2px solid var(--ink);
  font-weight: 800;
}

.text-link:hover {
  color: var(--coral-dark);
  border-bottom-color: var(--coral-dark);
}

.quick-facts {
  margin: 32px 0 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  list-style: none;
}

.quick-facts li {
  padding: 7px 11px;
  border: 1px solid var(--ink);
  border-radius: 4px;
  background: var(--white);
  font-size: 13px;
  font-weight: 700;
}

.hero-art {
  position: relative;
  min-height: 540px;
  display: grid;
  place-items: center;
}

.phone-frame {
  position: relative;
  width: 270px;
  padding: 12px;
  border: 4px solid var(--ink);
  border-radius: 32px;
  background: var(--ink);
  box-shadow: 14px 14px 0 rgba(23, 23, 31, 0.22);
  transform: rotate(3deg);
}

.phone-frame::before {
  position: absolute;
  top: 17px;
  left: 50%;
  z-index: 2;
  width: 70px;
  height: 8px;
  content: "";
  border-radius: 10px;
  background: var(--ink);
  transform: translateX(-50%);
}

.phone-frame img {
  width: 100%;
  max-width: 318px;
  height: auto;
  border-radius: 21px;
}

.burst {
  position: absolute;
  padding: 12px 16px;
  border: 2px solid var(--ink);
  background: var(--yellow);
  box-shadow: 5px 5px 0 var(--ink);
  font-size: 14px;
  font-weight: 900;
  transform: rotate(-6deg);
}

.burst-top {
  top: 70px;
  right: 6px;
}

.burst-bottom {
  bottom: 80px;
  left: 0;
  color: var(--white);
  background: var(--coral);
  transform: rotate(5deg);
}

.stats-band {
  border-bottom: 2px solid var(--ink);
  background: var(--ink);
  color: var(--white);
}

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

.stat {
  min-height: 112px;
  padding: 24px 26px;
  border-right: 1px solid #4b4b54;
}

.stat:last-child {
  border-right: 0;
}

.stat strong {
  display: block;
  color: var(--yellow);
  font-size: 25px;
}

.stat span {
  color: #c8c8cf;
  font-size: 14px;
}

.content-section {
  padding: 92px 0;
}

.content-section.compact {
  padding: 68px 0;
}

.section-heading {
  margin: 0 0 42px;
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 24px;
}

.section-heading h2,
.article-section h2,
.faq-block h2 {
  margin: 0;
  font-size: clamp(30px, 4vw, 52px);
  line-height: 1.12;
  letter-spacing: 0;
}

.section-index {
  flex: 0 0 auto;
  color: var(--coral);
  font-size: 17px;
  font-weight: 900;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 18px;
}

.feature-card {
  min-height: 250px;
  padding: 28px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  background: var(--white);
  box-shadow: 6px 6px 0 var(--ink);
}

.feature-card:nth-child(1),
.feature-card:nth-child(4) {
  grid-column: span 7;
}

.feature-card:nth-child(2),
.feature-card:nth-child(3) {
  grid-column: span 5;
}

.feature-card:nth-child(1) {
  background: var(--coral);
}

.feature-card:nth-child(4) {
  background: var(--teal);
}

.feature-number {
  margin-bottom: 34px;
  display: block;
  font-size: 14px;
  font-weight: 900;
}

.feature-card h3 {
  margin: 0 0 10px;
  font-size: 25px;
  line-height: 1.25;
}

.feature-card p {
  margin: 0;
  color: #3e3e47;
}

.feature-card:nth-child(1) p,
.feature-card:nth-child(4) p {
  color: var(--ink);
}

.screens-band {
  overflow: hidden;
  border-top: 2px solid var(--ink);
  border-bottom: 2px solid var(--ink);
  background: var(--paper-deep);
}

.screens-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
}

.screen-item {
  margin: 0;
}

.screen-item img {
  width: 100%;
  max-width: 318px;
  height: auto;
  margin: 0 auto;
  border: 2px solid var(--ink);
  border-radius: 6px;
  box-shadow: 6px 6px 0 var(--ink);
}

.screen-item figcaption {
  max-width: 318px;
  margin: 18px auto 0;
}

.screen-item strong {
  display: block;
  font-size: 17px;
}

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

.route-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}

.route-card {
  min-height: 260px;
  padding: 30px;
  border-top: 6px solid var(--coral);
  background: var(--white);
}

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

.route-card:nth-child(3) {
  border-color: var(--yellow);
}

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

.route-card h3 {
  margin: 22px 0 12px;
  font-size: 26px;
}

.route-card p {
  margin: 0 0 24px;
  color: var(--muted);
}

.review-strip {
  border-top: 2px solid var(--ink);
  border-bottom: 2px solid var(--ink);
  background: var(--yellow);
}

.reviews-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.review {
  padding-left: 20px;
  border-left: 4px solid var(--ink);
}

.review blockquote {
  margin: 0 0 14px;
  font-size: 18px;
  font-weight: 700;
}

.review cite {
  font-size: 13px;
  font-style: normal;
}

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

.faq-item {
  border-bottom: 2px solid var(--ink);
}

.faq-question {
  width: 100%;
  min-height: 72px;
  padding: 18px 54px 18px 0;
  position: relative;
  border: 0;
  color: var(--ink);
  background: transparent;
  text-align: left;
  font-size: 18px;
  font-weight: 900;
  cursor: pointer;
}

.faq-question::after {
  position: absolute;
  top: 50%;
  right: 8px;
  width: 30px;
  height: 30px;
  content: "+";
  display: grid;
  place-items: center;
  border: 2px solid var(--ink);
  border-radius: 50%;
  transform: translateY(-50%);
}

.faq-question[aria-expanded="true"]::after {
  content: "−";
  color: var(--white);
  background: var(--ink);
}

.faq-answer {
  max-width: 900px;
  padding: 0 60px 22px 0;
  color: var(--muted);
}

.faq-answer p {
  margin: 0;
}

.cta-band {
  position: relative;
  overflow: hidden;
  border-top: 2px solid var(--ink);
  color: var(--white);
  background: var(--coral);
}

.cta-band::after {
  position: absolute;
  right: -60px;
  bottom: -90px;
  width: 300px;
  height: 300px;
  content: "";
  border: 48px solid var(--yellow);
  border-radius: 50%;
}

.cta-inner {
  position: relative;
  z-index: 2;
  padding-top: 62px;
  padding-bottom: 62px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
}

.cta-inner h2 {
  margin: 0;
  font-size: clamp(30px, 4vw, 50px);
  line-height: 1.12;
}

.site-footer {
  padding: 38px 0 26px;
  color: #d1d1d5;
  background: var(--ink);
}

.footer-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 30px;
}

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

.footer-brand p {
  max-width: 520px;
  margin: 16px 0 0;
  font-size: 13px;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  font-size: 14px;
}

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

.footer-bottom {
  margin-top: 30px;
  padding-top: 20px;
  display: flex;
  justify-content: space-between;
  gap: 20px;
  border-top: 1px solid #45454d;
  font-size: 12px;
}

.page-hero {
  padding: 78px 0 70px;
  border-bottom: 2px solid var(--ink);
  background-color: var(--paper-deep);
  background-image: radial-gradient(var(--ink) 1px, transparent 1px);
  background-size: 18px 18px;
}

.page-hero .hero-panel {
  max-width: 960px;
  padding: 42px;
  border: 2px solid var(--ink);
  background: var(--paper);
  box-shadow: var(--shadow);
}

.page-hero h1 {
  font-size: clamp(42px, 5vw, 64px);
}

.page-hero .lead {
  max-width: 780px;
  margin: 22px 0 0;
  color: #44444d;
  font-size: 18px;
}

.article-layout {
  display: grid;
  grid-template-columns: 250px minmax(0, 1fr);
  align-items: start;
  gap: 54px;
}

.article-aside {
  position: sticky;
  top: 104px;
  padding: 22px;
  border: 2px solid var(--ink);
  background: var(--white);
  box-shadow: 5px 5px 0 var(--ink);
}

.article-aside strong {
  display: block;
  margin-bottom: 12px;
}

.article-aside a {
  padding: 8px 0;
  display: block;
  border-bottom: 1px solid var(--line);
  color: var(--muted);
  font-size: 14px;
}

.article-aside a:last-child {
  border-bottom: 0;
}

.article-aside a:hover {
  color: var(--coral-dark);
}

.article-content {
  min-width: 0;
}

.article-section {
  padding: 8px 0 58px;
  scroll-margin-top: 104px;
}

.article-section h2,
.faq-block h2 {
  margin-bottom: 28px;
  font-size: clamp(28px, 4vw, 42px);
}

.article-section h3 {
  margin: 28px 0 10px;
  font-size: 22px;
}

.article-section p {
  margin: 0 0 18px;
  color: #42424b;
}

.step-list {
  margin: 0;
  padding: 0;
  display: grid;
  gap: 18px;
  list-style: none;
  counter-reset: steps;
}

.step-list li {
  position: relative;
  min-height: 150px;
  padding: 24px 26px 24px 92px;
  border: 2px solid var(--ink);
  border-radius: 6px;
  background: var(--white);
  counter-increment: steps;
}

.step-list li::before {
  position: absolute;
  top: 24px;
  left: 24px;
  width: 48px;
  height: 48px;
  content: counter(steps, decimal-leading-zero);
  display: grid;
  place-items: center;
  border: 2px solid var(--ink);
  border-radius: 50%;
  color: var(--white);
  background: var(--coral);
  font-weight: 900;
}

.step-list h3 {
  margin: 0 0 8px;
  font-size: 21px;
}

.step-list p {
  margin: 0;
}

.check-grid,
.mode-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 16px;
}

.check-item,
.mode-item {
  padding: 22px;
  border-left: 5px solid var(--teal);
  background: var(--paper-deep);
}

.check-item strong,
.mode-item strong {
  display: block;
  margin-bottom: 6px;
}

.check-item p,
.mode-item p {
  margin: 0;
  font-size: 14px;
}

.notice {
  padding: 20px 22px;
  border: 2px solid var(--ink);
  background: var(--yellow);
  box-shadow: 4px 4px 0 var(--ink);
}

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

.notice p {
  margin: 0;
  color: var(--ink);
}

.faq-block {
  padding-bottom: 58px;
  scroll-margin-top: 104px;
}

.related-band {
  border-top: 2px solid var(--ink);
  background: var(--teal);
}

.related-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 22px;
}

.related-card {
  padding: 28px;
  border: 2px solid var(--ink);
  background: var(--paper);
  box-shadow: 6px 6px 0 var(--ink);
}

.related-card h3 {
  margin: 0 0 10px;
  font-size: 24px;
}

.related-card p {
  margin: 0 0 18px;
  color: var(--muted);
}

@media (max-width: 900px) {
  .menu-toggle {
    display: block;
  }

  .site-nav {
    position: fixed;
    top: 74px;
    right: 0;
    left: 0;
    max-height: 0;
    padding: 0 20px;
    display: grid;
    overflow: hidden;
    border-bottom: 0 solid var(--ink);
    background: var(--paper);
    transition: max-height 220ms ease, padding 220ms ease, border-width 220ms ease;
  }

  .site-nav.open {
    max-height: 360px;
    padding-top: 18px;
    padding-bottom: 22px;
    border-bottom-width: 2px;
  }

  .site-nav > a:not(.download-button) {
    justify-content: center;
  }

  .hero::before {
    top: auto;
    bottom: 0;
    width: 100%;
    height: 43%;
    border-top: 2px solid var(--ink);
    border-left: 0;
  }

  .hero-shell {
    padding-top: 52px;
    grid-template-columns: 1fr;
    gap: 38px;
  }

  .hero-art {
    min-height: 510px;
  }

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

  .feature-card:nth-child(n) {
    grid-column: span 6;
  }

  .route-grid,
  .reviews-grid {
    grid-template-columns: 1fr;
  }

  .article-layout {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .article-aside {
    position: static;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
  }

  .article-aside strong {
    grid-column: 1 / -1;
  }
}

@media (max-width: 620px) {
  .nav-shell,
  .section-shell,
  .hero-shell {
    width: min(100% - 28px, 1180px);
  }

  .brand {
    font-size: 20px;
  }

  .hero h1,
  .page-hero h1 {
    font-size: 43px;
  }

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

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

  .hero-actions .download-button,
  .hero-actions .text-link {
    width: 100%;
    text-align: center;
  }

  .phone-frame {
    width: 238px;
  }

  .burst-top {
    right: -4px;
  }

  .stats-grid,
  .screens-grid,
  .check-grid,
  .mode-grid,
  .related-grid {
    grid-template-columns: 1fr;
  }

  .stat {
    border-right: 0;
    border-bottom: 1px solid #4b4b54;
  }

  .stat:last-child {
    border-bottom: 0;
  }

  .content-section {
    padding: 66px 0;
  }

  .feature-card:nth-child(n) {
    grid-column: 1 / -1;
  }

  .section-heading,
  .cta-inner,
  .footer-top,
  .footer-bottom {
    align-items: flex-start;
    flex-direction: column;
  }

  .page-hero {
    padding: 54px 0 48px;
  }

  .page-hero .hero-panel {
    padding: 26px 22px;
    box-shadow: 6px 6px 0 var(--ink);
  }

  .article-aside {
    grid-template-columns: 1fr;
  }

  .step-list li {
    padding: 82px 22px 24px;
  }

  .faq-answer {
    padding-right: 0;
  }
}

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