:root {
  --ink: #18212a;
  --muted: #586674;
  --soft: #edf3f6;
  --line: #d7e1e6;
  --paper: #ffffff;
  --canvas: #f6f9fa;
  --primary: #007da8;
  --primary-dark: #005c7e;
  --violet: #6656a5;
  --graphite: #25313b;
  --radius: 6px;
  --shadow: 0 18px 42px rgba(26, 45, 58, 0.12);
  --container: 1180px;
}

* {
  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;
  letter-spacing: 0;
}

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

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

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

.container,
.header-inner,
.hero-inner {
  width: min(var(--container), calc(100% - 48px));
  margin-inline: auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
}

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

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  min-width: max-content;
  font-size: 19px;
  font-weight: 800;
  color: var(--graphite);
}

.brand img {
  width: 42px;
  height: 42px;
  border-radius: 5px;
}

.site-nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 30px;
}

.site-nav a {
  position: relative;
  padding: 23px 0 20px;
  color: #43515e;
  font-size: 15px;
}

.site-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: -1px;
  height: 2px;
  background: transparent;
}

.site-nav a:hover,
.site-nav a.active {
  color: var(--primary-dark);
}

.site-nav a.active::after {
  background: var(--primary);
}

.header-download {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0 20px;
  color: #fff;
  background: var(--graphite);
  border-radius: 5px;
  font-size: 14px;
  font-weight: 700;
}

.menu-toggle {
  display: none;
  width: 42px;
  height: 42px;
  margin-left: auto;
  padding: 0;
  color: var(--graphite);
  background: var(--soft);
  border: 1px solid var(--line);
  border-radius: 5px;
  font-size: 21px;
  cursor: pointer;
}

.hero {
  overflow: hidden;
  background: linear-gradient(90deg, #f6fafb 0%, #ffffff 61%, #f1f5f7 100%);
  border-bottom: 1px solid var(--line);
}

.hero-inner {
  min-height: 630px;
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(420px, 0.95fr);
  align-items: center;
  gap: 76px;
  padding: 52px 0 48px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  margin-bottom: 14px;
  color: var(--primary-dark);
  font-size: 13px;
  font-weight: 800;
}

.eyebrow::before {
  content: "";
  width: 28px;
  height: 2px;
  margin-right: 10px;
  background: var(--primary);
}

.hero h1,
.page-hero h1 {
  margin: 0;
  max-width: 680px;
  color: var(--graphite);
  font-size: 54px;
  line-height: 1.15;
  font-weight: 850;
}

.hero-copy > p {
  max-width: 630px;
  margin: 24px 0 0;
  color: #4b5b68;
  font-size: 17px;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 30px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 24px;
  border: 1px solid transparent;
  border-radius: 5px;
  font-size: 15px;
  font-weight: 750;
  transition: transform 160ms ease, background-color 160ms ease, border-color 160ms ease;
}

.button:hover {
  transform: translateY(-1px);
}

.button-primary {
  color: #fff;
  background: var(--primary-dark);
}

.button-primary:hover {
  background: #004c69;
}

.button-secondary {
  color: var(--graphite);
  background: #fff;
  border-color: #aebcc4;
}

.hero-facts {
  display: flex;
  flex-wrap: wrap;
  gap: 20px;
  margin: 26px 0 0;
  padding: 0;
  list-style: none;
  color: #52616d;
  font-size: 14px;
}

.hero-facts li::before {
  content: "✓";
  margin-right: 7px;
  color: var(--primary);
  font-weight: 900;
}

.hero-media {
  position: relative;
  min-height: 500px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero-media::before {
  content: "";
  position: absolute;
  inset: 38px 20px 48px 74px;
  background: #e7eef1;
  border: 1px solid #cddadf;
  border-radius: var(--radius);
}

.device-frame {
  position: relative;
  z-index: 2;
  width: 250px;
  padding: 10px 10px 12px;
  background: #11171b;
  border: 1px solid #28353e;
  border-radius: 22px;
  box-shadow: var(--shadow);
}

.device-frame img {
  width: 100%;
  max-width: 400px;
  border-radius: 0 0 14px 14px;
}

.device-bar {
  height: 25px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 4px;
  color: #cbd4d8;
  font-size: 10px;
}

.device-bar span:first-child,
.device-bar span:last-child {
  width: 5px;
  height: 5px;
  background: #6ed6ec;
  border-radius: 50%;
}

.status-panel {
  position: absolute;
  z-index: 3;
  right: 0;
  bottom: 34px;
  width: 224px;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 15px 16px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 5px;
  box-shadow: 0 12px 28px rgba(33, 51, 62, 0.12);
}

.status-dot {
  width: 10px;
  height: 10px;
  flex: 0 0 auto;
  background: #1c9a75;
  border-radius: 50%;
}

.status-panel strong,
.status-panel small {
  display: block;
}

.status-panel strong {
  font-size: 14px;
}

.status-panel small {
  color: var(--muted);
  font-size: 11px;
}

.swatch-strip {
  position: absolute;
  z-index: 1;
  left: 24px;
  top: 54px;
  display: grid;
  gap: 7px;
}

.swatch-strip span {
  width: 38px;
  height: 38px;
  border: 1px solid rgba(26, 46, 58, 0.08);
  border-radius: 4px;
}

.swatch-strip span:nth-child(1) { background: #22b8d6; }
.swatch-strip span:nth-child(2) { background: #6656a5; }
.swatch-strip span:nth-child(3) { background: #dfe9ed; }
.swatch-strip span:nth-child(4) { background: #26343d; }

.section {
  padding: 84px 0;
}

.section-heading {
  margin-bottom: 34px;
}

.section-heading h2,
.download-band h2,
.link-band h2,
.faq-toolbar h2 {
  margin: 0;
  color: var(--graphite);
  font-size: 34px;
  line-height: 1.25;
}

.section-heading h2::after {
  content: "";
  display: block;
  width: 48px;
  height: 3px;
  margin-top: 13px;
  background: var(--primary);
}

.section-features {
  background: var(--paper);
}

.feature-table {
  border-top: 1px solid var(--line);
}

.feature-row {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr) 80px;
  align-items: center;
  gap: 28px;
  padding: 26px 4px;
  border-bottom: 1px solid var(--line);
}

.feature-index {
  color: var(--primary);
  font-size: 13px;
  font-weight: 800;
}

.feature-row h3 {
  margin: 0 0 5px;
  font-size: 20px;
}

.feature-row p {
  margin: 0;
  color: var(--muted);
}

.feature-tag {
  justify-self: end;
  padding: 4px 10px;
  color: #4b5c68;
  background: var(--soft);
  border: 1px solid var(--line);
  border-radius: 4px;
  font-size: 12px;
}

.section-preview {
  background: var(--canvas);
  border-block: 1px solid var(--line);
}

.preview-layout {
  display: grid;
  grid-template-columns: 0.75fr 1.25fr;
  align-items: center;
  gap: 74px;
}

.preview-copy h3 {
  margin: 0 0 16px;
  font-size: 28px;
  line-height: 1.35;
}

.preview-copy p {
  margin: 0 0 22px;
  color: var(--muted);
}

.text-link {
  color: var(--primary-dark);
  font-weight: 750;
}

.preview-gallery {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  align-items: end;
  gap: 24px;
}

.preview-gallery figure,
.guide-images figure {
  margin: 0;
}

.preview-gallery img,
.guide-images img {
  width: min(100%, 300px);
  max-width: 400px;
  margin: 0 auto;
  border: 1px solid #2d3338;
  border-radius: 6px;
  box-shadow: 0 12px 28px rgba(23, 36, 45, 0.12);
}

.preview-gallery figure:nth-child(2) {
  transform: translateY(22px);
}

.preview-gallery figcaption,
.guide-images figcaption {
  margin-top: 13px;
  color: var(--muted);
  font-size: 13px;
  text-align: center;
}

.section-checklist {
  padding-bottom: 36px;
}

.checklist {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin: 0;
  padding: 0;
  list-style: none;
  border-block: 1px solid var(--line);
}

.checklist li {
  min-height: 160px;
  padding: 26px;
  border-right: 1px solid var(--line);
}

.checklist li:last-child {
  border-right: 0;
}

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

.checklist strong {
  margin-bottom: 10px;
  font-size: 18px;
}

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

.section-scenarios {
  padding-top: 48px;
}

.scenario-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 20px;
}

.scenario-grid blockquote {
  margin: 0;
  padding: 24px;
  color: #475762;
  background: var(--canvas);
  border: 1px solid var(--line);
  border-top: 3px solid var(--violet);
  border-radius: var(--radius);
}

.scenario-grid span {
  display: block;
  margin-bottom: 8px;
  color: var(--graphite);
  font-weight: 800;
}

.section-links {
  padding: 0;
}

.link-band {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  padding: 0;
  overflow: hidden;
  background: var(--graphite);
  border-radius: 6px;
}

.link-band > div {
  padding: 44px;
}

.link-band > div + div {
  color: var(--graphite);
  background: #dcecf1;
}

.link-band h2 {
  margin: 6px 0 12px;
  color: #fff;
}

.link-band > div + div h2 {
  color: var(--graphite);
}

.link-summary {
  max-width: 470px;
  margin: 0 0 22px;
  color: #c7d1d7;
}

.link-band > div + div .link-summary {
  color: #53626d;
}

.link-kicker {
  color: #78d6e9;
  font-size: 13px;
  font-weight: 800;
}

.link-band > div + div .link-kicker {
  color: var(--primary-dark);
}

.button-dark {
  color: var(--graphite);
  background: #fff;
}

.button-light {
  color: #fff;
  background: var(--graphite);
}

.section-faq-preview {
  background: #fff;
}

.faq-preview-list {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.faq-preview-list a {
  min-height: 132px;
  padding: 23px;
  background: var(--canvas);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.faq-preview-list strong,
.faq-preview-list span {
  display: block;
}

.faq-preview-list strong {
  margin-bottom: 8px;
  color: var(--graphite);
}

.faq-preview-list span {
  color: var(--muted);
  font-size: 14px;
}

.download-band {
  padding: 44px 0;
  color: #fff;
  background: var(--primary-dark);
}

.download-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
}

.download-band h2 {
  margin-top: 4px;
  color: #fff;
}

.download-band span {
  color: #c8e9f2;
  font-size: 14px;
}

.download-actions {
  display: flex;
  gap: 12px;
}

.button-white {
  color: var(--primary-dark);
  background: #fff;
}

.button-outline-white {
  color: #fff;
  background: transparent;
  border-color: rgba(255, 255, 255, 0.65);
}

.site-footer {
  padding: 42px 0 30px;
  color: #b8c2c8;
  background: #151d23;
}

.footer-inner {
  text-align: center;
}

.footer-brand {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  color: #fff;
}

.footer-brand img {
  width: 34px;
  height: 34px;
  border-radius: 4px;
}

.site-footer nav {
  display: flex;
  justify-content: center;
  gap: 24px;
  margin: 20px 0;
  font-size: 14px;
}

.site-footer nav a:hover {
  color: #fff;
}

.disclaimer,
.copyright {
  margin: 0;
  font-size: 13px;
  text-align: center;
}

.copyright {
  margin-top: 8px;
  color: #82909a;
}

.page-hero {
  padding: 76px 0 70px;
  background: #f3f7f8;
  border-bottom: 1px solid var(--line);
}

.page-hero-inner {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(300px, 0.6fr);
  align-items: center;
  gap: 80px;
}

.page-hero h1 {
  font-size: 46px;
}

.page-hero p {
  max-width: 720px;
  margin: 20px 0 0;
  color: var(--muted);
  font-size: 17px;
}

.page-aside {
  padding: 25px 27px;
  background: #fff;
  border: 1px solid var(--line);
  border-left: 3px solid var(--primary);
  border-radius: var(--radius);
}

.page-aside ul {
  margin: 12px 0 0;
  padding-left: 20px;
  color: var(--muted);
  font-size: 14px;
}

.guide-layout {
  display: grid;
  grid-template-columns: 220px minmax(0, 1fr);
  align-items: start;
  gap: 68px;
  padding-top: 72px;
  padding-bottom: 90px;
}

.guide-nav {
  position: sticky;
  top: 98px;
  display: grid;
  border-top: 2px solid var(--graphite);
}

.guide-nav span {
  padding: 15px 10px;
  color: var(--graphite);
  font-weight: 800;
}

.guide-nav a {
  padding: 11px 10px;
  color: var(--muted);
  border-top: 1px solid var(--line);
  font-size: 14px;
}

.guide-nav a:hover {
  color: var(--primary-dark);
}

.guide-section {
  position: relative;
  padding: 0 0 62px;
}

.guide-section + .guide-section {
  padding-top: 10px;
  border-top: 1px solid var(--line);
}

.guide-section h2 {
  margin: 0 0 18px;
  font-size: 30px;
}

.guide-section p {
  margin: 0 0 16px;
  color: #44535f;
}

.step-number {
  display: inline-block;
  margin: 20px 0 7px;
  color: var(--primary);
  font-size: 13px;
  font-weight: 800;
}

.notice {
  display: grid;
  grid-template-columns: 70px 1fr;
  gap: 16px;
  margin-top: 24px;
  padding: 20px;
  background: #edf7f8;
  border-left: 3px solid var(--primary);
}

.notice span {
  color: var(--muted);
}

.guide-images {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 28px;
  margin: 30px 0;
  padding: 30px;
  background: var(--canvas);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.guide-images img {
  width: min(100%, 260px);
}

.inline-steps {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1px;
  margin: 28px 0 0;
  padding: 1px;
  background: var(--line);
  list-style: none;
}

.inline-steps li {
  padding: 20px;
  background: #fff;
}

.inline-steps strong,
.inline-steps span {
  display: block;
}

.inline-steps span {
  margin-top: 5px;
  color: var(--muted);
  font-size: 14px;
}

.faq-hero {
  background: linear-gradient(90deg, #f4f8f9, #eef5f7);
}

.faq-hero h1 span + span::before {
  content: "";
}

.faq-section {
  padding-top: 76px;
  padding-bottom: 90px;
}

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

.faq-toolbar .eyebrow {
  margin-bottom: 8px;
}

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

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

.faq-item button {
  width: 100%;
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  padding: 18px 4px;
  color: var(--graphite);
  background: transparent;
  border: 0;
  font: inherit;
  font-weight: 750;
  text-align: left;
  cursor: pointer;
}

.faq-item button i {
  width: 32px;
  height: 32px;
  flex: 0 0 auto;
  display: grid;
  place-items: center;
  color: var(--primary-dark);
  background: var(--soft);
  border: 1px solid var(--line);
  border-radius: 50%;
  font-style: normal;
}

.faq-answer {
  max-width: 900px;
  padding: 0 56px 24px 4px;
}

.faq-answer p {
  margin: 0;
  color: var(--muted);
}

.faq-note {
  margin-top: 40px;
  padding: 24px;
  background: var(--canvas);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.faq-note p {
  margin: 6px 0 0;
  color: var(--muted);
}

.faq-note a,
.guide-content a {
  color: var(--primary-dark);
  text-decoration: underline;
  text-underline-offset: 3px;
}

@media (max-width: 960px) {
  .header-inner {
    min-height: 64px;
  }

  .menu-toggle {
    display: grid;
    place-items: center;
  }

  .header-download {
    display: none;
  }

  .site-nav {
    position: absolute;
    top: 64px;
    left: 24px;
    right: 24px;
    display: none;
    margin: 0;
    padding: 8px;
    background: #fff;
    border: 1px solid var(--line);
    border-radius: 6px;
    box-shadow: var(--shadow);
  }

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

  .site-nav a {
    padding: 11px 12px;
  }

  .site-nav a::after {
    display: none;
  }

  .hero-inner {
    grid-template-columns: 1fr;
    gap: 20px;
    padding: 42px 0 34px;
  }

  .hero-media {
    min-height: 365px;
    align-items: center;
  }

  .device-frame {
    width: 190px;
  }

  .hero-media::before {
    inset: 26px 10% 28px;
  }

  .status-panel {
    right: 7%;
    bottom: 12px;
  }

  .swatch-strip {
    left: 9%;
    top: 36px;
  }

  .preview-layout,
  .page-hero-inner {
    grid-template-columns: 1fr;
    gap: 42px;
  }

  .checklist {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .checklist li:nth-child(2) {
    border-right: 0;
  }

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

  .scenario-grid,
  .faq-preview-list {
    grid-template-columns: 1fr;
  }

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

  .guide-nav {
    position: static;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .guide-nav span {
    grid-column: 1 / -1;
  }
}

@media (max-width: 640px) {
  .container,
  .header-inner,
  .hero-inner {
    width: min(100% - 32px, var(--container));
  }

  .brand {
    font-size: 17px;
  }

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

  .site-nav {
    left: 16px;
    right: 16px;
  }

  .hero-inner {
    min-height: auto;
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 10px;
    padding-top: 32px;
  }

  .hero h1,
  .page-hero h1 {
    font-size: 36px;
    line-height: 1.18;
  }

  .hero-copy > p,
  .page-hero p {
    margin-top: 16px;
    font-size: 15px;
  }

  .hero-actions {
    margin-top: 22px;
  }

  .button {
    min-height: 46px;
    padding-inline: 19px;
  }

  .hero-facts {
    gap: 8px 16px;
    margin-top: 17px;
    font-size: 12px;
  }

  .hero-media {
    min-height: 310px;
  }

  .device-frame {
    width: 152px;
    padding: 6px 6px 8px;
    border-radius: 15px;
  }

  .device-bar {
    height: 18px;
    font-size: 8px;
  }

  .device-frame img {
    border-radius: 0 0 10px 10px;
  }

  .status-panel {
    right: 0;
    bottom: 8px;
    width: 184px;
    padding: 11px;
  }

  .status-panel strong {
    font-size: 12px;
  }

  .status-panel small {
    font-size: 9px;
  }

  .swatch-strip {
    left: 1%;
    top: 28px;
  }

  .swatch-strip span {
    width: 28px;
    height: 28px;
  }

  .section {
    padding: 58px 0;
  }

  .section-heading {
    margin-bottom: 24px;
  }

  .section-heading h2,
  .download-band h2,
  .link-band h2,
  .faq-toolbar h2 {
    font-size: 28px;
  }

  .feature-row {
    grid-template-columns: 38px minmax(0, 1fr);
    gap: 12px;
  }

  .feature-tag {
    display: none;
  }

  .feature-row h3 {
    font-size: 18px;
  }

  .feature-row p {
    font-size: 14px;
  }

  .preview-layout {
    gap: 34px;
  }

  .preview-gallery {
    gap: 12px;
  }

  .preview-gallery img {
    width: 100%;
  }

  .preview-gallery figcaption {
    font-size: 11px;
  }

  .preview-gallery figure:nth-child(2) {
    transform: translateY(12px);
  }

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

  .checklist li,
  .checklist li:nth-child(2) {
    min-height: 0;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

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

  .section-checklist {
    padding-bottom: 20px;
  }

  .section-scenarios {
    padding-top: 40px;
  }

  .link-band {
    width: 100%;
    grid-template-columns: 1fr;
    border-radius: 0;
  }

  .link-band > div {
    padding: 34px 16px;
  }

  .download-inner,
  .faq-toolbar {
    align-items: flex-start;
    flex-direction: column;
  }

  .download-actions {
    width: 100%;
  }

  .download-actions .button {
    flex: 1;
  }

  .page-hero {
    padding: 52px 0;
  }

  .page-hero-inner {
    gap: 30px;
  }

  .faq-hero h1 span {
    display: block;
  }

  .guide-layout,
  .faq-section {
    padding-top: 50px;
    padding-bottom: 64px;
  }

  .guide-nav {
    grid-template-columns: 1fr;
  }

  .guide-section h2 {
    font-size: 26px;
  }

  .guide-images {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
    padding: 14px;
  }

  .guide-images figcaption {
    font-size: 10px;
  }

  .inline-steps {
    grid-template-columns: 1fr;
  }

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

  .faq-toolbar {
    gap: 16px;
  }

  .faq-item button {
    min-height: 66px;
  }

  .faq-answer {
    padding-right: 4px;
  }

  .site-footer nav {
    flex-wrap: wrap;
  }
}

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

  .button {
    transition: none;
  }
}