:root {
  --ink: #171a1f;
  --muted: #667078;
  --paper: #f6f7f4;
  --white: #ffffff;
  --teal: #12bfa6;
  --teal-dark: #087f72;
  --teal-soft: #dff8f3;
  --coral: #ff6b5e;
  --coral-soft: #fff0ed;
  --yellow: #f5ca52;
  --line: #dfe3df;
  --shadow: 0 18px 50px rgba(23, 26, 31, 0.1);
  --max: 1160px;
}

* {
  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: 1.7;
  letter-spacing: 0;
}

body.menu-open {
  overflow: hidden;
}

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

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

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

:focus-visible {
  outline: 3px solid rgba(18, 191, 166, 0.4);
  outline-offset: 3px;
}

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

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 200;
  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;
  background: rgba(246, 247, 244, 0.96);
  border-bottom: 1px solid rgba(23, 26, 31, 0.1);
  backdrop-filter: blur(16px);
}

.nav-shell {
  min-height: 72px;
  display: flex;
  align-items: center;
  gap: 32px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  flex: 0 0 auto;
  font-size: 1.15rem;
  font-weight: 800;
}

.brand img {
  width: 38px;
  height: 38px;
  border-radius: 7px;
}

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

.site-nav a {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  padding: 0 14px;
  color: #495159;
  font-size: 0.94rem;
  font-weight: 650;
  border-bottom: 2px solid transparent;
}

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

.button {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 22px;
  color: var(--white);
  background: var(--ink);
  border: 1px solid var(--ink);
  border-radius: 6px;
  font-size: 0.96rem;
  font-weight: 750;
  box-shadow: 4px 4px 0 var(--teal);
  transition: transform 180ms ease, box-shadow 180ms ease, background 180ms ease;
}

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

.button-light {
  color: var(--ink);
  background: var(--white);
  border-color: var(--white);
  box-shadow: 4px 4px 0 var(--coral);
}

.button-light:hover {
  color: var(--white);
  background: var(--coral);
  border-color: var(--coral);
  box-shadow: 2px 2px 0 var(--white);
}

.menu-toggle {
  width: 44px;
  height: 44px;
  display: none;
  place-items: center;
  margin-left: auto;
  padding: 0;
  background: transparent;
  border: 1px solid var(--line);
  border-radius: 6px;
}

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

.menu-toggle span {
  position: relative;
}

.menu-toggle span::before {
  position: absolute;
  top: -6px;
}

.menu-toggle span::after {
  position: absolute;
  top: 6px;
}

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

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

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

.hero {
  position: relative;
  overflow: hidden;
  padding: 76px 0 62px;
  background: var(--white);
  border-bottom: 1px solid var(--line);
}

.hero::before {
  position: absolute;
  top: 0;
  bottom: 0;
  left: calc(50% + 150px);
  width: 1px;
  background: var(--line);
  content: "";
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(360px, 0.98fr);
  align-items: center;
  gap: 68px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin: 0 0 18px;
  color: var(--teal-dark);
  font-size: 0.78rem;
  font-weight: 800;
  text-transform: uppercase;
}

.eyebrow::before {
  width: 24px;
  height: 3px;
  background: var(--coral);
  content: "";
}

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

h1,
h2,
h3 {
  line-height: 1.22;
}

h1 {
  max-width: 720px;
  margin-bottom: 22px;
  font-size: clamp(2.45rem, 6vw, 5.3rem);
  letter-spacing: 0;
}

.hero-copy > p {
  max-width: 650px;
  margin-bottom: 26px;
  color: #4c555c;
  font-size: 1.08rem;
}

.hero-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  margin-bottom: 34px;
}

.text-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  color: var(--teal-dark);
  font-weight: 750;
}

.text-link::after {
  content: "→";
  transition: transform 180ms ease;
}

.text-link:hover::after {
  transform: translateX(4px);
}

.fact-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  max-width: 590px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.fact {
  padding: 15px 14px 15px 0;
}

.fact + .fact {
  padding-left: 18px;
  border-left: 1px solid var(--line);
}

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

.fact strong {
  font-size: 0.95rem;
}

.fact span {
  color: var(--muted);
  font-size: 0.78rem;
}

.hero-visual {
  position: relative;
  min-height: 520px;
  display: grid;
  place-items: center;
}

.phone-frame {
  position: relative;
  width: 248px;
  padding: 10px;
  background: var(--ink);
  border: 1px solid #050607;
  border-radius: 28px;
  box-shadow: var(--shadow);
}

.phone-frame::before {
  position: absolute;
  top: 15px;
  left: 50%;
  z-index: 2;
  width: 64px;
  height: 14px;
  background: var(--ink);
  border-radius: 0 0 9px 9px;
  content: "";
  transform: translateX(-50%);
}

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

.hero-visual .phone-frame:first-child {
  margin-left: -130px;
  transform: rotate(-3deg);
}

.hero-visual .phone-frame.secondary {
  position: absolute;
  right: 2px;
  bottom: 2px;
  width: 206px;
  transform: rotate(4deg);
}

.visual-note {
  position: absolute;
  top: 42px;
  right: 0;
  width: 148px;
  padding: 12px 14px;
  background: var(--yellow);
  border: 1px solid var(--ink);
  border-radius: 6px;
  font-size: 0.82rem;
  font-weight: 750;
  box-shadow: 4px 4px 0 var(--ink);
}

.section {
  padding: 86px 0;
}

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

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

.section-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 30px;
  margin-bottom: 36px;
}

.section-heading h2 {
  max-width: 720px;
  margin-bottom: 0;
  font-size: clamp(2rem, 4vw, 3.3rem);
}

.section-index {
  color: var(--coral);
  font-weight: 850;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.feature-item {
  min-height: 272px;
  padding: 28px;
  background: var(--paper);
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.feature-mark {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  margin-bottom: 54px;
  color: var(--white);
  background: var(--ink);
  border-radius: 50%;
  font-weight: 850;
}

.feature-item:nth-child(2) .feature-mark,
.feature-item:nth-child(4) .feature-mark {
  color: var(--ink);
  background: var(--teal);
}

.feature-item h3 {
  margin-bottom: 10px;
  font-size: 1.2rem;
}

.feature-item p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 0.94rem;
}

.preview-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
}

.preview-item {
  margin: 0;
}

.preview-device {
  padding: 8px;
  background: #0b0d10;
  border: 1px solid #30343b;
  border-radius: 26px;
  transition: transform 220ms ease;
}

.preview-item:hover .preview-device {
  transform: translateY(-8px);
}

.preview-device img {
  width: 100%;
  max-width: 400px;
  height: auto;
  border-radius: 19px;
}

.preview-item figcaption {
  padding: 14px 4px 0;
  color: #c8ced2;
  font-size: 0.9rem;
}

.preview-item strong {
  display: block;
  color: var(--white);
  font-size: 1rem;
}

.path-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}

.path-card {
  min-height: 290px;
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  padding: 34px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.path-card.coral {
  background: var(--coral-soft);
  border-color: #ffc7c1;
}

.path-card.teal {
  background: var(--teal-soft);
  border-color: #a8e9dd;
}

.path-number {
  margin-bottom: 50px;
  color: var(--muted);
  font-size: 0.8rem;
  font-weight: 800;
}

.path-card h3 {
  margin-bottom: 12px;
  font-size: 1.65rem;
}

.path-card p {
  max-width: 490px;
  margin-bottom: 24px;
  color: #535d63;
}

.path-card .text-link {
  margin-top: auto;
}

.quote-grid {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 70px;
  align-items: start;
}

.quote-lead h2 {
  margin-bottom: 20px;
  font-size: clamp(2rem, 4vw, 3.2rem);
}

.quote-lead p {
  color: #bcc4c8;
}

.quote-list {
  border-top: 1px solid #3a3f46;
}

.quote {
  margin: 0;
  padding: 24px 0;
  border-bottom: 1px solid #3a3f46;
}

.quote p {
  margin-bottom: 12px;
  font-size: 1.05rem;
}

.quote cite {
  color: var(--teal);
  font-size: 0.84rem;
  font-style: normal;
  font-weight: 750;
}

.faq-list {
  border-top: 1px solid var(--line);
}

.faq-list details {
  border-bottom: 1px solid var(--line);
}

.faq-list summary {
  position: relative;
  padding: 22px 48px 22px 0;
  cursor: pointer;
  font-weight: 750;
  list-style: none;
}

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

.faq-list summary::after {
  position: absolute;
  top: 21px;
  right: 8px;
  color: var(--teal-dark);
  content: "+";
  font-size: 1.35rem;
  line-height: 1;
}

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

.faq-list details p {
  max-width: 880px;
  padding: 0 48px 22px 0;
  margin-bottom: 0;
  color: var(--muted);
}

.cta-band {
  padding: 54px 0;
  color: var(--white);
  background: var(--teal-dark);
}

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

.cta-layout h2 {
  margin-bottom: 8px;
  font-size: clamp(1.7rem, 4vw, 2.7rem);
}

.cta-layout p {
  margin-bottom: 0;
  color: #d7fff8;
}

.site-footer {
  padding: 46px 0 30px;
  color: #bcc3c6;
  background: #0e1013;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 38px;
  align-items: start;
}

.footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 16px;
  color: var(--white);
  font-size: 1.1rem;
  font-weight: 800;
}

.footer-brand img {
  width: 34px;
  height: 34px;
  border-radius: 6px;
}

.footer-copy {
  max-width: 660px;
  margin-bottom: 8px;
  font-size: 0.84rem;
}

.footer-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 22px;
}

.footer-nav a {
  color: var(--white);
  font-size: 0.9rem;
}

.copyright {
  padding-top: 24px;
  margin-top: 28px;
  border-top: 1px solid #2c3036;
  font-size: 0.78rem;
}

.inner-hero {
  padding: 70px 0 54px;
  background: var(--white);
  border-bottom: 1px solid var(--line);
}

.inner-hero h1 {
  max-width: 900px;
  margin-bottom: 20px;
  font-size: clamp(2.3rem, 5vw, 4.5rem);
}

.inner-hero p {
  max-width: 760px;
  margin-bottom: 0;
  color: var(--muted);
  font-size: 1.05rem;
}

.breadcrumb {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 24px;
  color: var(--muted);
  font-size: 0.82rem;
}

.breadcrumb a:hover {
  color: var(--teal-dark);
}

.content-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 70px;
  align-items: start;
}

.article-section {
  padding-bottom: 56px;
  margin-bottom: 56px;
  border-bottom: 1px solid var(--line);
}

.article-section:last-child {
  padding-bottom: 0;
  margin-bottom: 0;
  border-bottom: 0;
}

.article-section h2 {
  margin-bottom: 24px;
  font-size: clamp(1.7rem, 3.5vw, 2.6rem);
}

.article-section h3 {
  margin: 28px 0 10px;
  font-size: 1.18rem;
}

.article-section p,
.article-section li {
  color: #4f585f;
}

.article-section ul,
.article-section ol {
  padding-left: 1.25rem;
}

.step-list {
  display: grid;
  gap: 0;
  border-top: 1px solid var(--line);
}

.step {
  display: grid;
  grid-template-columns: 74px minmax(0, 1fr);
  gap: 24px;
  padding: 28px 0;
  border-bottom: 1px solid var(--line);
}

.step-count {
  width: 54px;
  height: 54px;
  display: grid;
  place-items: center;
  color: var(--white);
  background: var(--ink);
  border-radius: 50%;
  font-weight: 850;
}

.step h3 {
  margin: 0 0 10px;
}

.step p {
  margin-bottom: 12px;
}

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

.note-box {
  padding: 22px;
  margin: 24px 0;
  background: var(--teal-soft);
  border-left: 4px solid var(--teal);
}

.note-box strong {
  display: block;
  margin-bottom: 4px;
}

.note-box p {
  margin-bottom: 0;
  color: #38544f;
}

.article-image {
  width: min(100%, 320px);
  margin: 26px auto 0;
  padding: 8px;
  background: var(--ink);
  border-radius: 24px;
}

.article-image img {
  width: 100%;
  max-width: 400px;
  height: auto;
  border-radius: 17px;
}

.side-nav {
  position: sticky;
  top: 98px;
  padding-left: 20px;
  border-left: 3px solid var(--teal);
}

.side-nav strong {
  display: block;
  margin-bottom: 10px;
}

.side-nav a {
  display: block;
  padding: 6px 0;
  color: var(--muted);
  font-size: 0.88rem;
}

.side-nav a:hover {
  color: var(--teal-dark);
}

.side-download {
  margin-top: 20px;
}

.function-table {
  width: 100%;
  border-collapse: collapse;
  background: var(--white);
}

.function-table th,
.function-table td {
  padding: 16px;
  text-align: left;
  vertical-align: top;
  border: 1px solid var(--line);
}

.function-table th {
  width: 25%;
  background: var(--teal-soft);
}

.topic-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 18px;
}

.topic {
  padding: 24px;
  background: var(--white);
  border: 1px solid var(--line);
  border-radius: 8px;
}

.topic h3 {
  margin-top: 0;
}

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

.reveal {
  opacity: 1;
  transform: none;
}

.reveal.visible {
  opacity: 1;
  transform: none;
}

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

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

  .reveal {
    opacity: 1;
    transform: none;
  }
}

@media (max-width: 960px) {
  .menu-toggle {
    display: grid;
  }

  .site-nav {
    position: fixed;
    top: 72px;
    right: 0;
    bottom: 0;
    left: 0;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 20px;
    background: var(--paper);
  }

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

  .site-nav a {
    min-height: 56px;
    border-bottom: 1px solid var(--line);
  }

  .nav-download {
    display: none;
  }

  .hero::before {
    display: none;
  }

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

  .hero-visual {
    max-width: 570px;
    width: 100%;
    margin-inline: auto;
  }

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

  .preview-grid {
    grid-template-columns: repeat(2, minmax(0, 280px));
    justify-content: center;
  }

  .content-layout {
    grid-template-columns: 1fr;
  }

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

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

  .nav-shell {
    min-height: 64px;
  }

  .site-nav {
    top: 64px;
  }

  .hero,
  .inner-hero {
    padding-top: 48px;
  }

  .hero {
    padding-top: 30px;
    padding-bottom: 22px;
  }

  h1 {
    font-size: 2.55rem;
  }

  .hero-copy h1 {
    margin-bottom: 12px;
  }

  .hero-copy > p {
    margin-bottom: 18px;
    font-size: 0.98rem;
  }

  .hero-actions {
    margin-bottom: 14px;
  }

  .hero-grid {
    gap: 18px;
  }

  .fact-row {
    display: none;
  }

  .fact + .fact {
    padding-left: 0;
    border-top: 1px solid var(--line);
    border-left: 0;
  }

  .hero-visual {
    min-height: 150px;
  }

  .hero-visual .phone-frame:first-child {
    width: 86px;
    margin-left: -54px;
    padding: 5px;
    border-radius: 14px;
  }

  .hero-visual .phone-frame.secondary {
    right: 86px;
    width: 74px;
    padding: 5px;
    border-radius: 14px;
  }

  .hero-visual .phone-frame img {
    border-radius: 10px;
  }

  .hero-visual .phone-frame::before {
    top: 7px;
    width: 28px;
    height: 6px;
  }

  .visual-note {
    top: 0;
    right: 8px;
    width: 108px;
    padding: 9px 10px;
    font-size: 0.7rem;
  }

  .section {
    padding: 62px 0;
  }

  .section-heading {
    align-items: start;
    flex-direction: column-reverse;
    gap: 8px;
  }

  .feature-grid,
  .preview-grid,
  .path-grid,
  .quote-grid,
  .topic-grid {
    grid-template-columns: 1fr;
  }

  .feature-item {
    min-height: 0;
  }

  .feature-mark {
    margin-bottom: 32px;
  }

  .preview-grid {
    width: min(100%, 310px);
    margin-inline: auto;
  }

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

  .step {
    grid-template-columns: 48px minmax(0, 1fr);
    gap: 16px;
  }

  .step-count {
    width: 42px;
    height: 42px;
  }

  .function-table,
  .function-table tbody,
  .function-table tr,
  .function-table th,
  .function-table td {
    display: block;
    width: 100%;
  }

  .function-table tr {
    margin-bottom: 14px;
  }
}