:root {
  color-scheme: light;
  --ink: #172026;
  --muted: #5f6b74;
  --line: #dfe6ea;
  --paper: #ffffff;
  --soft: #f5f8f7;
  --soft-2: #eef5f1;
  --teal: #3759C1;
  --teal-dark: #294399;
  --cobalt: #3759C1;
  --amber: #e09b18;
  --coral: #d95b43;
  --shadow: 0 18px 48px rgba(23, 32, 38, 0.12);
  --radius: 8px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Noto Sans SC", "Microsoft YaHei", "PingFang SC", sans-serif;
  color: var(--ink);
  background: var(--paper);
  line-height: 1.7;
}

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

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

.container {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid rgba(223, 230, 234, 0.9);
  backdrop-filter: blur(14px);
}

.nav {
  min-height: 74px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  min-width: 184px;
}

.brand img {
  width: 158px;
  height: auto;
}

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

.nav-links a {
  padding: 10px 13px;
  border-radius: 6px;
  color: #293943;
  font-size: 15px;
  font-weight: 600;
}

.nav-links a:hover,
.nav-links a.is-active {
  background: var(--soft-2);
  color: var(--teal-dark);
}

.nav-action {
  flex: 0 0 auto;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 11px 18px;
  border: 1px solid transparent;
  border-radius: var(--radius);
  background: var(--teal);
  color: #fff;
  font-weight: 700;
  font-size: 15px;
  cursor: pointer;
  transition: transform 160ms ease, box-shadow 160ms ease, background 160ms ease;
}

.button:hover {
  background: var(--teal-dark);
  box-shadow: 0 10px 24px rgba(15, 118, 110, 0.18);
  transform: translateY(-1px);
}

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

.button.secondary:hover {
  background: var(--soft);
  box-shadow: none;
}

.button.cobalt {
  background: var(--cobalt);
}

.button.cobalt:hover {
  background: #1b449d;
}

.hero {
  min-height: calc(100vh - 74px);
  display: grid;
  align-items: center;
  padding: 52px 0 40px;
  background:
    linear-gradient(90deg, rgba(245, 248, 247, 0.96), rgba(255, 255, 255, 0.86)),
    repeating-linear-gradient(135deg, rgba(15, 118, 110, 0.08) 0 1px, transparent 1px 16px);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.02fr) minmax(340px, 0.98fr);
  align-items: center;
  gap: 58px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--teal-dark);
  font-size: 14px;
  font-weight: 800;
  letter-spacing: 0;
}

.nowrap {
  white-space: nowrap;
}

h1,
h2,
h3 {
  margin: 0;
  line-height: 1.2;
}

h1 {
  max-width: 760px;
  font-size: clamp(38px, 5vw, 68px);
  letter-spacing: 0;
}

.hero-copy {
  margin: 22px 0 0;
  max-width: 660px;
  color: #34454f;
  font-size: 19px;
}

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

.trust-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin-top: 34px;
  max-width: 720px;
}

.trust-item {
  border-left: 4px solid var(--teal);
  background: rgba(255, 255, 255, 0.72);
  padding: 13px 14px;
}

.trust-item strong {
  display: block;
  font-size: 22px;
}

.trust-item span {
  color: var(--muted);
  font-size: 13px;
}

.scanner-panel {
  position: relative;
  min-height: 520px;
  background: #f8fbfa;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow: hidden;
}

.scanner-top {
  height: 56px;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 0 18px;
  background: #172026;
}

.dot {
  width: 11px;
  height: 11px;
  border-radius: 999px;
  background: var(--coral);
}

.dot:nth-child(2) {
  background: var(--amber);
}

.dot:nth-child(3) {
  background: #42a56b;
}

.scan-bed {
  margin: 24px;
  height: 275px;
  border: 1px solid #cbd7dc;
  border-radius: 6px;
  background:
    linear-gradient(180deg, rgba(36, 87, 197, 0.1), transparent 22%),
    linear-gradient(90deg, rgba(15, 118, 110, 0.22) 0 2px, transparent 2px 18px),
    #fff;
  position: relative;
  overflow: hidden;
}

.scan-bed::before {
  content: "";
  position: absolute;
  inset: 32px 34px;
  background:
    linear-gradient(135deg, rgba(217, 91, 67, 0.22), transparent 46%),
    linear-gradient(45deg, rgba(15, 118, 110, 0.2), transparent 46%),
    #f4eadc;
  border: 9px solid #fff;
  box-shadow: 0 10px 24px rgba(23, 32, 38, 0.12);
}

.scan-bed::after {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 42%;
  width: 18px;
  background: rgba(15, 118, 110, 0.22);
  box-shadow: 0 0 32px rgba(15, 118, 110, 0.4);
  animation: scanline 3.8s ease-in-out infinite alternate;
}

@keyframes scanline {
  from {
    transform: translateX(-145px);
  }
  to {
    transform: translateX(145px);
  }
}

.panel-controls {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  padding: 0 24px 24px;
}

.control-chip {
  padding: 14px;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 6px;
}

.control-chip b {
  display: block;
  font-size: 14px;
}

.control-chip span {
  color: var(--muted);
  font-size: 12px;
}

section {
  padding: 82px 0;
}

.section-alt {
  background: var(--soft);
}

.section-head {
  max-width: 760px;
  margin-bottom: 34px;
}

.section-head.center {
  margin-left: auto;
  margin-right: auto;
  text-align: center;
}

.section-head h2 {
  font-size: clamp(28px, 3.3vw, 44px);
}

.section-head p {
  color: var(--muted);
  font-size: 17px;
  margin: 14px 0 0;
}

.grid {
  display: grid;
  gap: 20px;
}

.grid.three {
  grid-template-columns: repeat(3, 1fr);
}

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

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

.card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  padding: 24px;
}

.card h3 {
  font-size: 21px;
  margin-bottom: 10px;
}

.card p,
.card li {
  color: var(--muted);
}

.icon-box {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  margin-bottom: 18px;
  border-radius: 7px;
  background: var(--soft-2);
  color: var(--teal-dark);
  font-weight: 900;
}

.feature-list {
  margin: 18px 0 0;
  padding: 0;
  list-style: none;
}

.feature-list li {
  position: relative;
  padding-left: 22px;
  margin: 8px 0;
}

.feature-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.78em;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--teal);
}

.split {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(0, 1.1fr);
  gap: 42px;
  align-items: center;
}

.scenario-band {
  display: grid;
  grid-template-columns: 1fr 1fr;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: #fff;
}

.scenario-copy {
  padding: 34px;
}

.scenario-visual {
  min-height: 280px;
  background:
    linear-gradient(135deg, rgba(36, 87, 197, 0.16), transparent 52%),
    linear-gradient(45deg, rgba(224, 155, 24, 0.2), transparent 50%),
    repeating-linear-gradient(0deg, rgba(23, 32, 38, 0.06) 0 1px, transparent 1px 22px),
    #eef5f1;
  position: relative;
}

.scenario-visual::before,
.scenario-visual::after {
  content: "";
  position: absolute;
  background: #fff;
  border: 1px solid #d6e0e4;
  box-shadow: 0 12px 26px rgba(23, 32, 38, 0.12);
}

.scenario-visual::before {
  width: 46%;
  height: 58%;
  top: 18%;
  left: 16%;
}

.scenario-visual::after {
  width: 34%;
  height: 42%;
  right: 15%;
  bottom: 16%;
  transform: rotate(4deg);
}

.quote-card {
  min-height: 220px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.quote-card blockquote {
  margin: 0;
  color: #263640;
  font-size: 18px;
}

.quote-card cite {
  color: var(--muted);
  font-style: normal;
  font-size: 14px;
  margin-top: 22px;
}

.page-hero {
  padding: 76px 0 56px;
  background:
    linear-gradient(90deg, rgba(245, 248, 247, 0.98), rgba(255, 255, 255, 0.92)),
    repeating-linear-gradient(135deg, rgba(36, 87, 197, 0.07) 0 1px, transparent 1px 16px);
}

.page-hero h1 {
  font-size: clamp(36px, 4.8vw, 58px);
}

.page-hero p {
  max-width: 760px;
  color: var(--muted);
  font-size: 18px;
}

.download-card {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr) auto;
  gap: 20px;
  align-items: center;
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.os-mark {
  width: 72px;
  height: 72px;
  display: grid;
  place-items: center;
  border-radius: 8px;
  background: var(--soft-2);
  color: var(--teal-dark);
  font-size: 30px;
  font-weight: 900;
}

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

.meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.tag {
  display: inline-flex;
  align-items: center;
  min-height: 28px;
  padding: 4px 9px;
  border-radius: 5px;
  background: var(--soft);
  color: #33454f;
  font-size: 13px;
  font-weight: 700;
}

.faq details {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  padding: 18px 20px;
}

.faq details + details {
  margin-top: 12px;
}

.faq summary {
  cursor: pointer;
  font-weight: 800;
}

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

.source-note {
  color: var(--muted);
  font-size: 13px;
  margin-top: 24px;
}

.site-footer {
  padding: 48px 0;
  background: #172026;
  color: #dbe4e8;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.2fr repeat(2, 0.8fr);
  gap: 28px;
}

.site-footer img {
  width: 160px;
}

.site-footer h2,
.site-footer h3 {
  font-size: 16px;
  color: #fff;
  margin-bottom: 12px;
}

.site-footer p,
.site-footer a,
.site-footer li {
  color: #aebbc3;
  font-size: 14px;
}

.footer-links {
  margin: 0;
  padding: 0;
  list-style: none;
}

.footer-links li + li {
  margin-top: 8px;
}

.footer-bottom {
  margin-top: 34px;
  padding-top: 20px;
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  color: #aebbc3;
  font-size: 13px;
}

.modal {
  position: fixed;
  inset: 0;
  z-index: 50;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 22px;
  background: rgba(23, 32, 38, 0.54);
}

.modal.is-open {
  display: flex;
}

.modal-dialog {
  width: min(760px, 100%);
  max-height: calc(100vh - 44px);
  overflow: auto;
  border-radius: var(--radius);
  background: #fff;
  box-shadow: var(--shadow);
}

.modal-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
  padding: 26px 28px 18px;
  border-bottom: 1px solid var(--line);
}

.modal-head p {
  margin: 7px 0 0;
  color: var(--muted);
}

.modal-close {
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  cursor: pointer;
  font-size: 24px;
  line-height: 1;
}

.modal-body {
  padding: 26px 28px 30px;
}

.qr-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 18px;
  margin-top: 22px;
}

.qr-item {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px;
  text-align: center;
}

.qr-item img {
  width: 164px;
  height: 164px;
  margin: 0 auto 12px;
}

.qr-item b {
  display: block;
}

.qr-item span {
  color: var(--muted);
  font-size: 13px;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}

@media (max-width: 980px) {
  .nav {
    align-items: flex-start;
    padding: 14px 0;
    flex-direction: column;
  }

  .nav-action {
    width: 100%;
  }

  .nav-action .button {
    width: 100%;
  }

  .hero {
    min-height: auto;
  }

  .hero-grid,
  .split,
  .scenario-band,
  .footer-grid {
    grid-template-columns: 1fr;
  }

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

  .scanner-panel {
    min-height: 460px;
  }
}

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

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

  .nav-links a {
    padding: 8px 10px;
    font-size: 14px;
  }

  .hero,
  section,
  .page-hero {
    padding: 46px 0;
  }

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

  .trust-row,
  .panel-controls,
  .grid.three,
  .grid.four,
  .grid.two,
  .download-card,
  .qr-grid {
    grid-template-columns: 1fr;
  }

  .download-card {
    align-items: start;
  }

  .download-card .button {
    width: 100%;
  }

  .scenario-copy,
  .card {
    padding: 20px;
  }

  .scanner-panel {
    min-height: auto;
  }

  .scan-bed {
    height: 220px;
    margin: 16px;
  }
}