:root {
  --ink: #173042;
  --ink-soft: #49636c;
  --sky: #35b8d4;
  --sky-pale: #dff5f7;
  --leaf: #52b788;
  --leaf-dark: #2f8569;
  --coral: #f06a5f;
  --sun: #f3bf43;
  --paper: #f7faf8;
  --white: #ffffff;
  --line: #d6e1de;
  --shadow: 0 18px 48px rgba(23, 48, 66, 0.12);
  --content: min(1180px, calc(100% - 40px));
}

* {
  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.menu-open {
  overflow: hidden;
}

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

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

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

:focus-visible {
  outline: 3px solid var(--sun);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  top: 8px;
  left: 8px;
  z-index: 200;
  padding: 9px 14px;
  color: var(--white);
  background: var(--ink);
  transform: translateY(-140%);
}

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: 72px;
  border-bottom: 1px solid rgba(214, 225, 222, 0.9);
  background: rgba(247, 250, 248, 0.96);
  backdrop-filter: blur(12px);
}

.nav-wrap {
  width: var(--content);
  height: 100%;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.brand {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-size: 20px;
  font-weight: 800;
  line-height: 1;
}

.brand img {
  width: 42px;
  height: 42px;
  border-radius: 10px;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: 7px;
}

.main-nav a {
  min-height: 42px;
  padding: 8px 13px;
  display: inline-flex;
  align-items: center;
  border-radius: 6px;
  font-weight: 700;
  color: var(--ink-soft);
}

.main-nav a:hover,
.main-nav a[aria-current="page"] {
  color: var(--ink);
  background: var(--sky-pale);
}

.download-button {
  min-width: 126px;
  min-height: 46px;
  padding: 11px 24px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border: 2px solid var(--ink);
  border-radius: 6px;
  color: var(--white);
  background: var(--ink);
  font-weight: 800;
  line-height: 1.2;
  box-shadow: 5px 5px 0 var(--sun);
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.download-button:hover {
  background: var(--leaf-dark);
  transform: translate(-2px, -2px);
  box-shadow: 7px 7px 0 var(--sun);
}

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

.nav-download {
  min-width: 112px;
  min-height: 40px;
  padding: 8px 18px;
  box-shadow: 4px 4px 0 var(--coral);
}

.menu-button {
  position: relative;
  width: 44px;
  height: 44px;
  padding: 0;
  display: none;
  place-items: center;
  border: 0;
  color: var(--ink);
  background: transparent;
  cursor: pointer;
}

.menu-button span,
.menu-button::before,
.menu-button::after {
  position: absolute;
  left: 10px;
  width: 24px;
  height: 2px;
  display: block;
  background: currentColor;
  content: "";
  transition: transform 160ms ease, opacity 160ms ease;
}

.menu-button span {
  top: 21px;
}

.menu-button::before {
  top: 14px;
}

.menu-button::after {
  top: 28px;
}

.menu-open .menu-button span {
  opacity: 0;
}

.menu-open .menu-button::before {
  transform: translateY(7px) rotate(45deg);
}

.menu-open .menu-button::after {
  transform: translateY(-7px) rotate(-45deg);
}

.main-nav .download-button,
.main-nav .download-button:hover {
  color: var(--white);
}

.hero {
  position: relative;
  min-height: calc(100vh - 72px);
  min-height: min(820px, calc(100svh - 72px));
  overflow: hidden;
  display: grid;
  align-items: center;
  color: var(--white);
  background: var(--ink);
}

.hero-media {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.hero::after {
  position: absolute;
  inset: 0;
  background: rgba(16, 35, 47, 0.52);
  content: "";
}

.hero-inner {
  position: relative;
  z-index: 1;
  width: var(--content);
  margin: 0 auto;
  padding: 88px 0 128px;
}

.hero-copy {
  width: min(650px, 100%);
}

.eyebrow {
  margin: 0 0 20px;
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 14px;
  font-weight: 800;
  text-transform: uppercase;
}

.eyebrow::before {
  width: 35px;
  height: 5px;
  display: block;
  background: var(--sun);
  content: "";
}

.hero h1,
.page-hero h1 {
  margin: 0;
  font-size: 72px;
  line-height: 1.08;
  letter-spacing: 0;
}

.hero-summary {
  max-width: 590px;
  margin: 24px 0 0;
  font-size: 19px;
  line-height: 1.85;
}

.hero-actions {
  margin-top: 34px;
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.hero-meta {
  display: flex;
  gap: 18px;
  color: rgba(255, 255, 255, 0.86);
  font-size: 14px;
  font-weight: 700;
}

.hero-strip {
  position: absolute;
  right: 0;
  bottom: 0;
  left: 0;
  z-index: 2;
  min-height: 78px;
  color: var(--ink);
  background: var(--white);
}

.hero-strip-inner {
  width: var(--content);
  min-height: 78px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  align-items: center;
}

.hero-strip-item {
  padding: 8px 26px;
  border-left: 1px solid var(--line);
  font-size: 14px;
  font-weight: 700;
}

.hero-strip-item:first-child {
  padding-left: 0;
  border-left: 0;
}

.hero-strip-item strong {
  display: block;
  color: var(--leaf-dark);
  font-size: 19px;
}

.section {
  padding: 92px 0;
}

.section-sky {
  background: var(--sky-pale);
}

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

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

.container {
  width: var(--content);
  margin: 0 auto;
}

.section-heading {
  margin: 0 0 42px;
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  gap: 28px;
}

.section-heading h2 {
  max-width: 720px;
  margin: 0;
  font-size: 46px;
  line-height: 1.18;
  letter-spacing: 0;
}

.section-number {
  color: var(--coral);
  font-size: 15px;
  font-weight: 900;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 18px;
}

.feature-card {
  min-height: 285px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--white);
  box-shadow: 0 10px 30px rgba(23, 48, 66, 0.05);
}

.feature-card:nth-child(2) {
  border-top: 5px solid var(--leaf);
}

.feature-card:nth-child(3) {
  border-top: 5px solid var(--coral);
}

.feature-card:nth-child(4) {
  border-top: 5px solid var(--sun);
}

.feature-card:first-child {
  border-top: 5px solid var(--sky);
}

.feature-icon {
  width: 52px;
  height: 52px;
  margin-bottom: 34px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: var(--ink);
  background: var(--sky-pale);
  font-size: 23px;
  font-weight: 900;
}

.feature-card h3 {
  margin: 0 0 12px;
  font-size: 21px;
  line-height: 1.35;
}

.feature-card p {
  margin: 0;
  color: var(--ink-soft);
}

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

.showcase-item {
  margin: 0;
}

.showcase-item img {
  width: 100%;
  max-width: 390px;
  height: auto;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 28px;
  box-shadow: 0 18px 30px rgba(0, 0, 0, 0.2);
}

.showcase-item figcaption {
  padding: 17px 4px 0;
  color: rgba(255, 255, 255, 0.78);
  font-size: 14px;
}

.showcase-item strong {
  display: block;
  color: var(--white);
  font-size: 17px;
}

.path-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.path-card {
  position: relative;
  min-height: 300px;
  padding: 32px;
  overflow: hidden;
  border: 2px solid var(--ink);
  border-radius: 6px;
  background: var(--white);
}

.path-card::after {
  position: absolute;
  right: -35px;
  bottom: -45px;
  width: 130px;
  height: 130px;
  border-radius: 50%;
  background: var(--sky-pale);
  content: "";
}

.path-card:nth-child(2)::after {
  background: #e0f3e9;
}

.path-card:nth-child(3)::after {
  background: #fff0dc;
}

.path-label {
  display: inline-block;
  margin-bottom: 48px;
  color: var(--coral);
  font-size: 13px;
  font-weight: 900;
}

.path-card h3 {
  position: relative;
  z-index: 1;
  margin: 0 0 12px;
  font-size: 25px;
}

.path-card p {
  position: relative;
  z-index: 1;
  margin: 0 0 24px;
  color: var(--ink-soft);
}

.text-link {
  position: relative;
  z-index: 1;
  padding-bottom: 3px;
  border-bottom: 2px solid var(--coral);
  font-weight: 800;
}

.review-layout {
  display: grid;
  grid-template-columns: 0.8fr 1.2fr;
  gap: 64px;
  align-items: start;
}

.score-block {
  padding-top: 20px;
}

.score-number {
  display: block;
  color: var(--sun);
  font-size: 118px;
  font-weight: 900;
  line-height: 0.9;
}

.score-label {
  margin-top: 20px;
  color: rgba(255, 255, 255, 0.7);
}

.review-list {
  display: grid;
  gap: 16px;
}

.review {
  margin: 0;
  padding: 27px 28px;
  border-left: 5px solid var(--leaf);
  background: rgba(255, 255, 255, 0.08);
}

.review:nth-child(2) {
  border-left-color: var(--sky);
}

.review:nth-child(3) {
  border-left-color: var(--coral);
}

.review p {
  margin: 0 0 9px;
  font-size: 17px;
}

.review cite {
  color: rgba(255, 255, 255, 0.65);
  font-size: 13px;
  font-style: normal;
}

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

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

.faq-question {
  width: 100%;
  padding: 24px 48px 24px 0;
  position: relative;
  border: 0;
  color: var(--ink);
  background: transparent;
  font: inherit;
  font-size: 18px;
  font-weight: 800;
  text-align: left;
  cursor: pointer;
}

.faq-question::after {
  position: absolute;
  top: 50%;
  right: 8px;
  width: 24px;
  height: 24px;
  display: grid;
  place-items: center;
  content: "+";
  transform: translateY(-50%);
  font-size: 24px;
}

.faq-question[aria-expanded="true"]::after {
  content: "−";
}

.faq-answer {
  max-width: 850px;
  padding: 0 50px 24px 0;
  color: var(--ink-soft);
}

.faq-answer p {
  margin: 0;
}

.download-band {
  padding: 68px 0;
  color: var(--ink);
  background: var(--sun);
}

.download-band-inner {
  width: var(--content);
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
}

.download-band h2 {
  margin: 0;
  font-size: 42px;
  line-height: 1.2;
}

.download-band p,
.download-band .band-note {
  margin: 8px 0 0;
  color: #4d472d;
}

.page-hero {
  padding: 104px 0 74px;
  color: var(--white);
  background: var(--ink);
}

.page-hero .container {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 340px;
  gap: 60px;
  align-items: end;
}

.page-hero h1 {
  max-width: 800px;
  font-size: 64px;
}

.page-lead {
  margin: 24px 0 0;
  max-width: 760px;
  color: rgba(255, 255, 255, 0.78);
  font-size: 18px;
}

.page-fact {
  padding: 24px;
  border-left: 5px solid var(--sun);
  background: rgba(255, 255, 255, 0.08);
}

.page-fact strong {
  display: block;
  color: var(--sun);
  font-size: 28px;
}

.breadcrumb {
  margin-bottom: 28px;
  color: rgba(255, 255, 255, 0.62);
  font-size: 14px;
}

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

.content-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 64px;
  align-items: start;
}

.article h2 {
  margin: 58px 0 22px;
  font-size: 38px;
  line-height: 1.25;
}

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

.article h3 {
  margin: 32px 0 12px;
  font-size: 22px;
  line-height: 1.35;
}

.article p {
  margin: 0 0 18px;
  color: #334e58;
}

.article a {
  color: var(--leaf-dark);
  border-bottom: 1px solid currentColor;
  font-weight: 700;
}

.steps {
  display: grid;
  gap: 0;
  border-top: 2px solid var(--ink);
}

.step {
  display: grid;
  grid-template-columns: 86px minmax(0, 1fr);
  gap: 26px;
  padding: 30px 0;
  border-bottom: 1px solid var(--line);
}

.step-number {
  width: 62px;
  height: 62px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: var(--white);
  background: var(--coral);
  font-size: 20px;
  font-weight: 900;
}

.step h3 {
  margin-top: 0;
}

.checklist {
  margin: 24px 0;
  padding: 26px 30px 26px 54px;
  border-left: 5px solid var(--leaf);
  background: #e7f5ed;
}

.checklist li {
  padding: 5px 0;
}

.notice {
  margin: 28px 0;
  padding: 24px 28px;
  border: 2px solid var(--sun);
  background: #fff9e8;
}

.notice strong {
  display: block;
  margin-bottom: 5px;
}

.side-nav {
  position: sticky;
  top: 100px;
  padding: 25px;
  border-top: 5px solid var(--sky);
  background: var(--white);
  box-shadow: var(--shadow);
}

.side-nav strong {
  display: block;
  margin-bottom: 14px;
}

.side-nav a {
  padding: 9px 0;
  display: block;
  border-top: 1px solid var(--line);
  color: var(--ink-soft);
  font-size: 14px;
}

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

.function-row {
  display: grid;
  grid-template-columns: 62px minmax(0, 1fr);
  gap: 22px;
  padding: 27px 0;
  border-top: 1px solid var(--line);
}

.function-row:last-child {
  border-bottom: 1px solid var(--line);
}

.function-index {
  color: var(--sky);
  font-size: 26px;
  font-weight: 900;
}

.function-row h3 {
  margin-top: 0;
}

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

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

.troubleshoot-table th {
  background: var(--sky-pale);
}

.site-footer {
  padding: 58px 0 32px;
  color: rgba(255, 255, 255, 0.72);
  background: #10232f;
}

.footer-grid {
  width: var(--content);
  margin: 0 auto 38px;
  display: grid;
  grid-template-columns: 1.4fr 0.8fr 0.8fr;
  gap: 48px;
}

.footer-brand {
  margin-bottom: 18px;
  color: var(--white);
}

.footer-note {
  max-width: 520px;
  margin: 0;
  font-size: 14px;
}

.footer-column strong {
  display: block;
  margin-bottom: 12px;
  color: var(--white);
}

.footer-column a {
  display: block;
  padding: 5px 0;
}

.footer-column a:hover {
  color: var(--sun);
}

.copyright {
  width: var(--content);
  margin: 0 auto;
  padding-top: 26px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  display: flex;
  justify-content: space-between;
  gap: 18px;
  font-size: 13px;
}

.visual-note {
  margin-top: 16px;
  color: rgba(255, 255, 255, 0.55);
  font-size: 12px;
}

@media (max-width: 980px) {
  .feature-grid,
  .showcase-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

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

  .page-hero .container,
  .content-layout {
    grid-template-columns: 1fr;
  }

  .page-fact {
    max-width: 500px;
  }

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

@media (max-width: 760px) {
  :root {
    --content: min(calc(100% - 28px), 1180px);
  }

  .site-header {
    height: 64px;
  }

  .brand {
    font-size: 18px;
  }

  .brand img {
    width: 38px;
    height: 38px;
  }

  .menu-button {
    flex: 0 0 44px;
    display: flex !important;
    align-items: center;
    justify-content: center;
    border: 2px solid var(--ink);
    border-radius: 6px;
    background: var(--sun);
  }

  .menu-button span {
    position: static;
    width: auto;
    height: auto;
    margin: 0;
    background: transparent;
    font-size: 28px;
    line-height: 1;
  }

  .menu-button::before,
  .menu-button::after {
    display: none;
  }

  .menu-open .menu-button span {
    opacity: 1;
  }

  .main-nav {
    position: fixed;
    top: 64px;
    right: 0;
    bottom: 0;
    left: 0;
    padding: 30px 22px;
    display: none;
    align-items: stretch;
    flex-direction: column;
    gap: 8px;
    background: var(--paper);
  }

  .menu-open .main-nav {
    display: flex;
  }

  .main-nav a {
    min-height: 52px;
    padding: 12px 16px;
    font-size: 18px;
  }

  .nav-download {
    margin-top: 14px;
    color: var(--white) !important;
    background: var(--ink) !important;
  }

  .hero {
    min-height: min(650px, calc(100svh - 64px));
  }

  .hero-media {
    object-position: 65% center;
  }

  .hero::after {
    background: rgba(16, 35, 47, 0.68);
  }

  .hero-inner {
    padding: 58px 0 194px;
  }

  .hero h1 {
    font-size: 46px;
    overflow-wrap: anywhere;
  }

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

  .hero-meta {
    gap: 10px;
    flex-direction: column;
  }

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

  .hero-strip-item {
    min-height: 69px;
    padding: 10px 14px;
    border-bottom: 1px solid var(--line);
  }

  .section {
    padding: 66px 0;
  }

  .section-heading {
    align-items: flex-start;
    flex-direction: column-reverse;
    gap: 8px;
    margin-bottom: 30px;
  }

  .feature-grid,
  .showcase-grid,
  .review-layout {
    grid-template-columns: 1fr;
  }

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

  .showcase-item {
    max-width: 390px;
    margin: 0 auto;
  }

  .download-band-inner,
  .copyright {
    align-items: flex-start;
    flex-direction: column;
  }

  .page-hero {
    padding: 72px 0 56px;
  }

  .section-heading h2 {
    font-size: 34px;
  }

  .score-number {
    font-size: 82px;
  }

  .download-band h2 {
    font-size: 34px;
  }

  .page-hero h1 {
    font-size: 44px;
    overflow-wrap: anywhere;
  }

  .article h2 {
    font-size: 30px;
  }

  .step {
    grid-template-columns: 58px minmax(0, 1fr);
    gap: 15px;
  }

  .step-number {
    width: 48px;
    height: 48px;
  }

  .function-row {
    grid-template-columns: 46px minmax(0, 1fr);
    gap: 12px;
  }

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

  .troubleshoot-table thead {
    position: absolute;
    width: 1px;
    height: 1px;
    overflow: hidden;
    clip: rect(0 0 0 0);
  }

  .troubleshoot-table tr {
    margin-bottom: 16px;
    border: 1px solid var(--line);
  }

  .troubleshoot-table td {
    border: 0;
    border-bottom: 1px solid var(--line);
  }

  .troubleshoot-table td::before {
    display: block;
    color: var(--coral);
    font-size: 12px;
    font-weight: 900;
    content: attr(data-label);
  }

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

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

  *,
  *::before,
  *::after {
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}