:root {
  --ink: #13262b;
  --ink-soft: #385057;
  --paper: #f7f8f6;
  --white: #ffffff;
  --teal: #00a6a6;
  --teal-dark: #007c7c;
  --coral: #ff5a5f;
  --yellow: #f4c64c;
  --line: #cad5d6;
  --shadow: 8px 8px 0 rgba(19, 38, 43, 0.14);
  --radius: 6px;
  --content: 1160px;
}

* {
  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;
  font-size: 16px;
  line-height: 1.75;
  letter-spacing: 0;
}

body::before {
  position: fixed;
  inset: 0;
  z-index: -2;
  content: "";
  opacity: 0.2;
  background-image: radial-gradient(circle, #13262b 1px, transparent 1px);
  background-size: 18px 18px;
  pointer-events: none;
}

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

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

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 2px solid var(--ink);
  background: rgba(247, 248, 246, 0.96);
  backdrop-filter: blur(12px);
}

.nav-wrap {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 24px;
  font-weight: 900;
  line-height: 1;
}

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

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

.nav-links a {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  padding: 8px 14px;
  border-bottom: 3px solid transparent;
  font-weight: 700;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  border-color: var(--coral);
}

.nav-links .nav-download {
  margin-left: 8px;
  color: var(--white);
  border: 2px solid var(--ink);
  background: var(--coral);
  box-shadow: 3px 3px 0 var(--ink);
}

.nav-links .nav-download:hover {
  border-color: var(--ink);
  transform: translate(1px, 1px);
  box-shadow: 2px 2px 0 var(--ink);
}

.menu-button {
  width: 44px;
  height: 44px;
  display: none;
  place-items: center;
  padding: 0;
  color: var(--ink);
  border: 2px solid var(--ink);
  border-radius: var(--radius);
  background: var(--yellow);
  font-size: 24px;
  cursor: pointer;
}

.hero {
  min-height: 620px;
  display: grid;
  align-items: center;
  position: relative;
  overflow: hidden;
  color: var(--white);
  border-bottom: 3px solid var(--ink);
  background-color: var(--ink);
}

.hero::before {
  position: absolute;
  inset: 0;
  content: "";
  opacity: 0.2;
  background-image: radial-gradient(circle, var(--teal) 1px, transparent 1px);
  background-size: 20px 20px;
}

.hero-visual {
  position: absolute;
  top: 11%;
  right: calc(10vw - 24px);
  width: 226px;
  z-index: 1;
  margin: 0;
  padding: 0;
  border: 3px solid var(--white);
  box-shadow: 12px 12px 0 var(--teal);
}

.hero-visual img {
  width: 100%;
  max-width: 400px;
  height: auto;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 680px;
  padding-block: 76px 92px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 16px;
  color: var(--yellow);
  font-size: 14px;
  font-weight: 900;
}

.eyebrow::before {
  width: 28px;
  height: 5px;
  content: "";
  background: currentColor;
}

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

h1,
h2,
h3 {
  line-height: 1.25;
}

h1 {
  max-width: 700px;
  margin-bottom: 20px;
  font-size: 76px;
  font-weight: 950;
}

.hero-copy {
  max-width: 600px;
  margin-bottom: 28px;
  color: #e8f1f1;
  font-size: 18px;
}

.button-row {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.button {
  min-height: 48px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 11px 22px;
  border: 2px solid var(--ink);
  border-radius: var(--radius);
  background: var(--teal);
  color: var(--white);
  font-weight: 900;
  box-shadow: 5px 5px 0 var(--ink);
  transition: transform 160ms ease, box-shadow 160ms ease;
}

.button::before {
  content: "↓";
  font-size: 20px;
  line-height: 1;
}

.button:hover {
  transform: translate(2px, 2px);
  box-shadow: 3px 3px 0 var(--ink);
}

.button.light {
  color: var(--ink);
  background: var(--yellow);
  box-shadow: 5px 5px 0 var(--white);
}

.hero-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 18px;
  margin-top: 30px;
  color: #d9e3e4;
  font-size: 14px;
  font-weight: 700;
}

.hero-meta span::before {
  margin-right: 7px;
  color: var(--yellow);
  content: "●";
}

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

.signal-list {
  min-height: 72px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  align-items: center;
  gap: 0;
  margin: 0;
  padding: 0;
  list-style: none;
}

.signal-list li {
  padding: 10px 20px;
  text-align: center;
  font-weight: 900;
  border-right: 2px solid var(--ink);
}

.signal-list li:first-child {
  border-left: 2px solid var(--ink);
}

.section {
  padding-block: 88px;
  border-bottom: 2px solid var(--ink);
}

.section.white {
  background: var(--white);
}

.section.ink {
  color: var(--white);
  background: var(--ink);
}

.section-head {
  max-width: 760px;
  margin-bottom: 42px;
}

.section-head h2 {
  margin-bottom: 12px;
  font-size: 50px;
  font-weight: 950;
}

.section-head p {
  margin-bottom: 0;
  color: var(--ink-soft);
  font-size: 17px;
}

.ink .section-head p {
  color: #bed0d1;
}

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

.feature-card {
  grid-column: span 4;
  min-height: 240px;
  padding: 26px;
  border: 2px solid var(--ink);
  border-radius: var(--radius);
  background: var(--white);
  box-shadow: var(--shadow);
}

.feature-card.wide {
  grid-column: span 8;
}

.feature-card.teal {
  color: var(--white);
  background: var(--teal-dark);
}

.feature-card.coral {
  color: var(--white);
  background: var(--coral);
}

.feature-number {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  margin-bottom: 30px;
  border: 2px solid currentColor;
  border-radius: 50%;
  font-weight: 950;
}

.feature-card h3 {
  margin-bottom: 10px;
  font-size: 24px;
}

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

.screen-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 24px;
  align-items: end;
}

.screen-figure {
  margin: 0;
}

.screen-figure:nth-child(2) {
  transform: translateY(-28px);
}

.screen-frame {
  max-width: 400px;
  margin-inline: auto;
  padding: 12px;
  border: 3px solid var(--ink);
  border-radius: 28px;
  background: var(--ink);
  box-shadow: 10px 10px 0 var(--teal);
}

.screen-frame img {
  width: 100%;
  max-width: 400px;
  border-radius: 16px;
}

.screen-figure figcaption {
  margin-top: 22px;
  font-weight: 800;
  text-align: center;
}

.journey {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 56px;
  align-items: start;
}

.journey h2 {
  margin-bottom: 18px;
  font-size: 54px;
}

.journey-steps {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: journey;
}

.journey-steps li {
  position: relative;
  min-height: 108px;
  padding: 22px 20px 22px 90px;
  border-top: 2px solid var(--ink);
  counter-increment: journey;
}

.journey-steps li:last-child {
  border-bottom: 2px solid var(--ink);
}

.journey-steps li::before {
  position: absolute;
  top: 20px;
  left: 18px;
  width: 48px;
  height: 48px;
  display: grid;
  place-items: center;
  color: var(--white);
  border: 2px solid var(--ink);
  border-radius: 50%;
  background: var(--coral);
  content: counter(journey, decimal-leading-zero);
  font-weight: 950;
}

.journey-steps strong {
  display: block;
  font-size: 20px;
}

.content-links {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}

.content-link {
  min-height: 250px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: 30px;
  color: var(--white);
  border: 2px solid var(--white);
  border-radius: var(--radius);
}

.content-link:first-child {
  background: var(--teal-dark);
}

.content-link:last-child {
  background: #9a3942;
}

.content-link h3 {
  max-width: 420px;
  margin-bottom: 16px;
  font-size: 30px;
}

.content-link span {
  font-weight: 900;
}

.content-link span::after {
  margin-left: 8px;
  content: "→";
}

.quote-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}

.quote-card {
  margin: 0;
  padding: 28px;
  border: 2px solid var(--ink);
  background: var(--white);
  box-shadow: 6px 6px 0 var(--yellow);
}

.quote-card p {
  font-size: 17px;
}

.quote-card footer {
  color: var(--teal-dark);
  font-weight: 900;
}

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

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

.faq-button {
  width: 100%;
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 18px 4px;
  color: var(--ink);
  border: 0;
  background: transparent;
  font: inherit;
  font-size: 18px;
  font-weight: 900;
  text-align: left;
  cursor: pointer;
}

.faq-button::after {
  flex: 0 0 auto;
  content: "+";
  font-size: 28px;
}

.faq-item.is-open .faq-button::after {
  content: "−";
}

.faq-answer {
  display: none;
  max-width: 880px;
  padding: 0 4px 22px;
  color: var(--ink-soft);
}

.faq-item.is-open .faq-answer {
  display: block;
}

.spaced-action {
  margin-top: 28px;
}

.cta-band {
  padding-block: 70px;
  color: var(--ink);
  border-bottom: 2px solid var(--ink);
  background: var(--yellow);
}

.cta-wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 36px;
}

.cta-wrap h2 {
  max-width: 720px;
  margin-bottom: 8px;
  font-size: 48px;
}

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

.page-hero {
  padding-block: 90px 76px;
  color: var(--white);
  border-bottom: 3px solid var(--ink);
  background: var(--ink);
}

.page-hero .container {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 50px;
  align-items: end;
}

.page-hero h1 {
  margin-bottom: 18px;
  font-size: 64px;
}

.page-hero p {
  max-width: 760px;
  margin-bottom: 0;
  color: #c7d7d8;
  font-size: 18px;
}

.page-mark {
  min-width: 150px;
  padding: 18px;
  color: var(--ink);
  border: 2px solid var(--white);
  background: var(--yellow);
  box-shadow: 8px 8px 0 var(--teal);
  font-size: 18px;
  font-weight: 950;
  text-align: center;
}

.article-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 260px;
  gap: 64px;
  align-items: start;
}

.article h2 {
  margin: 56px 0 18px;
  padding-bottom: 12px;
  border-bottom: 3px solid var(--teal);
  font-size: 32px;
}

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

.article h3 {
  margin: 32px 0 10px;
  font-size: 23px;
}

.article p,
.article li {
  color: #2e464c;
}

.article a {
  color: var(--teal-dark);
  font-weight: 800;
  text-decoration: underline;
  text-decoration-thickness: 2px;
  text-underline-offset: 3px;
}

.step-block {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 20px;
  margin: 26px 0;
  padding: 26px;
  border: 2px solid var(--ink);
  background: var(--white);
  box-shadow: 6px 6px 0 rgba(0, 166, 166, 0.35);
}

.step-index {
  width: 58px;
  height: 58px;
  display: grid;
  place-items: center;
  color: var(--white);
  border-radius: 50%;
  background: var(--coral);
  font-size: 20px;
  font-weight: 950;
}

.step-block h3 {
  margin-top: 0;
}

.notice {
  margin: 28px 0;
  padding: 22px 24px;
  border-left: 6px solid var(--coral);
  background: #fff1f1;
}

.article-figure {
  max-width: 400px;
  margin: 34px auto;
  padding: 12px;
  border: 2px solid var(--ink);
  background: var(--white);
  box-shadow: 8px 8px 0 var(--teal);
}

.article-figure img {
  width: 100%;
  max-width: 400px;
}

.article-figure figcaption {
  padding-top: 12px;
  font-size: 14px;
  font-weight: 700;
  text-align: center;
}

.side-nav {
  position: sticky;
  top: 98px;
  padding: 20px;
  border: 2px solid var(--ink);
  background: var(--white);
  box-shadow: 6px 6px 0 var(--yellow);
}

.side-nav strong {
  display: block;
  margin-bottom: 12px;
}

.side-nav a {
  display: block;
  padding: 8px 0;
  color: var(--ink-soft);
  border-bottom: 1px solid var(--line);
  font-weight: 700;
}

.side-nav .button {
  margin-top: 18px;
  color: var(--white);
  text-decoration: none;
}

.spec-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 16px;
}

.spec-item {
  padding: 22px;
  border: 2px solid var(--ink);
  background: var(--white);
}

.spec-item strong {
  display: block;
  margin-bottom: 6px;
  font-size: 18px;
}

.spec-item p {
  margin: 0;
}

.site-footer {
  padding-block: 44px 30px;
  color: #c3d0d2;
  background: #0b171a;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 40px;
  align-items: start;
}

.footer-brand {
  color: var(--white);
  margin-bottom: 14px;
}

.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
  justify-content: flex-end;
}

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

.disclaimer {
  margin-top: 28px;
  padding-top: 22px;
  border-top: 1px solid #294047;
  font-size: 13px;
}

.copyright {
  margin: 12px 0 0;
  font-size: 13px;
}

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

  .nav-links {
    position: absolute;
    top: 72px;
    right: 20px;
    left: 20px;
    display: none;
    padding: 14px;
    border: 2px solid var(--ink);
    background: var(--white);
    box-shadow: 6px 6px 0 var(--ink);
  }

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

  .nav-links .nav-download {
    margin-left: 0;
  }

  .hero {
    min-height: 680px;
  }

  .hero-visual {
    right: calc(5vw - 18px);
    opacity: 0.42;
  }

  .hero-content {
    max-width: 590px;
  }

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

  .signal-list li:nth-child(3) {
    border-left: 2px solid var(--ink);
  }

  .signal-list li:nth-child(-n + 2) {
    border-bottom: 2px solid var(--ink);
  }

  .feature-card,
  .feature-card.wide {
    grid-column: span 6;
  }

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

  .side-nav {
    position: static;
    order: -1;
  }

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

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

  .brand {
    font-size: 21px;
  }

  .hero {
    min-height: 0;
    display: block;
  }

  .hero-visual {
    position: relative;
    top: auto;
    right: auto;
    width: 190px;
    margin: 0 26px 52px auto;
    opacity: 1;
  }

  .hero-content {
    padding-block: 62px 28px;
  }

  h1 {
    font-size: 42px;
  }

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

  .button-row .button {
    width: 100%;
  }

  .hero-meta {
    display: grid;
    gap: 7px;
  }

  .signal-list {
    grid-template-columns: 1fr;
  }

  .signal-list li,
  .signal-list li:first-child,
  .signal-list li:nth-child(3) {
    border-right: 2px solid var(--ink);
    border-bottom: 2px solid var(--ink);
    border-left: 2px solid var(--ink);
  }

  .signal-list li:last-child {
    border-bottom: 0;
  }

  .section {
    padding-block: 64px;
  }

  .feature-card,
  .feature-card.wide {
    grid-column: span 12;
  }

  .screen-grid,
  .content-links,
  .spec-grid,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .screen-figure:nth-child(2) {
    transform: none;
  }

  .cta-wrap,
  .page-hero .container {
    align-items: flex-start;
    flex-direction: column;
    display: flex;
  }

  .page-hero {
    padding-block: 62px;
  }

  .page-hero h1 {
    font-size: 40px;
  }

  .section-head h2,
  .journey h2,
  .cta-wrap h2 {
    font-size: 36px;
  }

  .article-layout {
    gap: 36px;
  }

  .step-block {
    grid-template-columns: 1fr;
  }

  .footer-links {
    justify-content: flex-start;
  }
}

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

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