:root {
  --navy: #1a2332;
  --navy-mid: #243447;
  --blue: #2a9d8f;
  --blue-deep: #238276;
  --cad: #3d7ea6;
  --ink: #1b2633;
  --muted: #5b6a79;
  --line: #d7dee6;
  --line-strong: #c3ccd6;
  --bg: #f4f6f8;
  --paper: #ffffff;
  --accent-soft: #e6f4f2;
  --ok: #2d6a4f;
  --warn: #9a5b12;
  --hole: #c45c4a;
  --header-h: 64px;
  --max: 1120px;
  --font: "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.7;
  font-size: 16px;
}

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

a {
  color: var(--cad);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

h1,
h2,
h3,
h4 {
  margin: 0 0 0.6em;
  line-height: 1.3;
  font-weight: 650;
  color: var(--navy);
}

p {
  margin: 0 0 1em;
}

ul,
ol {
  margin: 0 0 1em;
  padding-left: 1.2em;
}

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

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

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: var(--header-h);
  gap: 16px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--navy);
  text-decoration: none;
  flex-shrink: 0;
}

.brand:hover {
  text-decoration: none;
}

.brand-mark {
  width: 28px;
  height: 28px;
}

.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
}

.brand-text strong {
  font-size: 14px;
  letter-spacing: 0.02em;
}

.brand-text span {
  font-size: 11px;
  color: var(--muted);
  font-weight: 400;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}

.lang-switch {
  display: inline-flex;
  border: 1px solid var(--line-strong);
  border-radius: 4px;
  overflow: hidden;
}

.lang-switch button {
  height: 32px;
  padding: 0 10px;
  border: 0;
  background: #fff;
  color: var(--muted);
  font: inherit;
  font-size: 12px;
  cursor: pointer;
}

.lang-switch button.is-active {
  background: var(--navy);
  color: #fff;
}

.lang-switch button:hover:not(.is-active) {
  background: var(--accent-soft);
}

.nav {
  display: flex;
  align-items: center;
  gap: 2px;
}

.nav a,
.nav-parent > span {
  display: block;
  padding: 8px 9px;
  color: var(--ink);
  font-size: 13px;
  border-radius: 4px;
}

.nav a:hover,
.nav-parent:hover > span {
  background: var(--accent-soft);
  text-decoration: none;
  color: var(--blue-deep);
}

.nav a.is-active,
.nav-parent.is-active > span {
  color: var(--blue-deep);
  font-weight: 650;
}

.nav-parent {
  position: relative;
}

.nav-parent > span {
  cursor: default;
}

.nav-parent > span::after {
  content: "";
  display: inline-block;
  width: 0;
  height: 0;
  margin-left: 5px;
  border-left: 4px solid transparent;
  border-right: 4px solid transparent;
  border-top: 5px solid currentColor;
  vertical-align: middle;
}

.dropdown {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  min-width: 180px;
  background: #fff;
  border: 1px solid var(--line);
  padding: 6px;
  z-index: 60;
}

.nav-parent:hover .dropdown,
.nav-parent:focus-within .dropdown {
  display: block;
}

.dropdown a {
  display: block;
  padding: 8px 10px;
  font-size: 13px;
}

.menu-toggle {
  display: none;
  width: 40px;
  height: 40px;
  border: 1px solid var(--line);
  background: #fff;
  cursor: pointer;
}

.menu-toggle span,
.menu-toggle span::before,
.menu-toggle span::after {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--navy);
  position: relative;
}

.menu-toggle span::before,
.menu-toggle span::after {
  content: "";
  position: absolute;
  left: 0;
}

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

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

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 40px;
  padding: 0 16px;
  background: var(--blue);
  color: #fff;
  font-size: 14px;
  border: 0;
  border-radius: 4px;
  cursor: pointer;
  text-decoration: none;
}

.btn:hover {
  background: var(--blue-deep);
  text-decoration: none;
  color: #fff;
}

.btn-light {
  background: #fff;
  color: var(--navy);
}

.btn-light:hover {
  background: var(--accent-soft);
  color: var(--blue-deep);
}

.btn-ghost {
  background: transparent;
  color: var(--navy);
  border: 1px solid var(--line-strong);
}

.btn-ghost:hover {
  background: var(--accent-soft);
  color: var(--blue-deep);
}

.hero {
  background: var(--navy);
  color: #d7e2ec;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 28px 28px;
  pointer-events: none;
}

.hero-inner {
  position: relative;
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 48px;
  align-items: center;
  min-height: 520px;
  padding: 56px 0 64px;
}

.kicker {
  display: inline-block;
  font-size: 12px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #7ecfc4;
  margin-bottom: 14px;
}

.hero h1 {
  color: #fff;
  font-size: clamp(28px, 4vw, 42px);
  font-weight: 650;
  margin-bottom: 16px;
}

.hero .lead {
  font-size: 17px;
  color: #c5d3e0;
  max-width: 38em;
}

.hero-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 28px;
}

.hero-panel {
  border: 1px solid rgba(255, 255, 255, 0.12);
  background: rgba(26, 35, 50, 0.55);
  padding: 20px;
}

.hero-panel h2 {
  color: #fff;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 14px;
}

.page-hero {
  background: var(--navy);
  color: #d7e2ec;
  padding: 48px 0 40px;
}

.page-hero h1 {
  color: #fff;
  font-size: clamp(24px, 3vw, 34px);
  margin-bottom: 10px;
}

.page-hero .lead {
  max-width: 42em;
  color: #c5d3e0;
  margin: 0;
}

.crumb {
  font-size: 13px;
  color: #8ea0b3;
  margin-bottom: 16px;
}

.crumb a {
  color: #b9cce0;
}

.crumb span {
  margin: 0 8px;
  color: #6d8298;
}

.section {
  padding: 72px 0;
}

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

.section-head {
  margin-bottom: 36px;
  max-width: 720px;
}

.section-index {
  font-size: 12px;
  letter-spacing: 0.16em;
  color: var(--blue);
  margin-bottom: 8px;
}

.section h2 {
  font-size: 28px;
}

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

.grid-2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

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

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

.card {
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 22px;
}

.card h3 {
  font-size: 17px;
  margin-bottom: 8px;
}

.card p:last-child,
.card ul:last-child {
  margin-bottom: 0;
}

.card a.more {
  display: inline-block;
  margin-top: 12px;
  font-size: 14px;
}

.card-link {
  display: block;
  color: inherit;
  text-decoration: none;
  height: 100%;
}

a.card.card-link:hover {
  border-color: var(--blue);
  text-decoration: none;
}

.num {
  font-size: 12px;
  color: var(--blue);
  letter-spacing: 0.08em;
  margin-bottom: 8px;
}

.chain {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 0;
}

.chain-item {
  position: relative;
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 18px 16px;
  text-align: left;
  color: inherit;
  text-decoration: none;
}

.chain-item + .chain-item {
  border-left: 0;
}

.chain-item:hover {
  background: var(--accent-soft);
  text-decoration: none;
}

.chain-item strong {
  display: block;
  color: var(--navy);
  margin-bottom: 6px;
}

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

.chain-item em {
  font-style: normal;
  font-size: 11px;
  color: var(--blue);
  letter-spacing: 0.08em;
}

.compare {
  width: 100%;
  border-collapse: collapse;
  background: var(--paper);
  font-size: 15px;
}

.compare th,
.compare td {
  border: 1px solid var(--line);
  padding: 14px 16px;
  text-align: left;
  vertical-align: top;
}

.compare th {
  background: var(--navy);
  color: #fff;
  font-weight: 600;
}

.compare td:first-child {
  width: 22%;
  color: var(--muted);
  background: #fafbfc;
}

.compare .bad {
  color: #7a3b2e;
}

.compare .good {
  color: var(--ok);
}

.matrix-item {
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 18px 16px;
}

.matrix-item strong {
  display: block;
  margin-bottom: 6px;
  color: var(--navy);
}

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

.format-pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 72px;
  height: 40px;
  padding: 0 14px;
  border: 1px solid var(--line);
  background: var(--paper);
  font-weight: 650;
  color: var(--navy);
  letter-spacing: 0.06em;
}

.steps {
  display: grid;
  gap: 0;
}

.step {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 20px;
  padding: 20px 0;
  border-bottom: 1px solid var(--line);
}

.step:last-child {
  border-bottom: 0;
}

.step-id {
  font-size: 13px;
  color: var(--blue);
  letter-spacing: 0.08em;
}

.cta-band {
  background: var(--navy-mid);
  color: #d5e0ea;
  padding: 48px 0;
}

.cta-band h2 {
  color: #fff;
}

.cta-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 24px;
}

.site-footer {
  background: var(--navy);
  color: #9aadb8;
  padding: 40px 0 24px;
  font-size: 13px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: 32px;
  margin-bottom: 28px;
}

.site-footer h3 {
  color: #e8eef3;
  font-size: 13px;
  margin-bottom: 12px;
}

.site-footer a {
  color: #b9c9d4;
}

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

.site-footer li {
  margin-bottom: 6px;
}

.footer-copy {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: 16px;
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 16px 0 0;
  padding: 0;
  list-style: none;
}

.tag-list li {
  border: 1px solid rgba(255, 255, 255, 0.16);
  color: #d5e4f0;
  font-size: 12px;
  padding: 4px 10px;
}

.split {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 40px;
  align-items: start;
}

.scan-frame {
  width: 100%;
  max-width: 420px;
  margin-left: auto;
}

.demo-layout {
  display: grid;
  grid-template-columns: 1.35fr 0.75fr;
  gap: 24px;
  align-items: start;
}

.demo-stage-wrap {
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 12px;
}

.demo-stage-label {
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 8px;
}

.demo-stage {
  position: relative;
  background: #0f1824;
  min-height: 420px;
  overflow: hidden;
}

.demo-stage canvas {
  display: block;
  width: 100%;
  height: 420px;
}

.demo-toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 12px;
}

.demo-stats dt {
  font-size: 12px;
  color: var(--muted);
  margin: 0 0 2px;
}

.demo-stats dd {
  margin: 0 0 14px;
  font-size: 18px;
  color: var(--navy);
  font-weight: 650;
}

.status-line {
  font-size: 13px;
  color: var(--muted);
  min-height: 1.6em;
  margin-top: 8px;
}

.status-line.is-error {
  color: #8a3b2e;
  font-weight: 600;
}

.module-nav {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  padding-top: 40px;
  border-top: 1px solid var(--line);
  margin-top: 48px;
}

.module-nav a {
  display: block;
  max-width: 46%;
  color: var(--ink);
  text-decoration: none;
  border: 1px solid var(--line);
  background: var(--paper);
  padding: 16px 18px;
}

.module-nav a:hover {
  border-color: var(--blue);
  text-decoration: none;
}

.module-nav small {
  display: block;
  color: var(--muted);
  font-size: 12px;
  margin-bottom: 4px;
}

.module-nav .next {
  margin-left: auto;
  text-align: right;
}

.legal {
  border-left: 3px solid var(--blue);
  padding: 8px 0 8px 16px;
}

.form {
  background: var(--paper);
  border: 1px solid var(--line);
  padding: 28px;
}

.form-row {
  margin-bottom: 16px;
}

.form label {
  display: block;
  font-size: 13px;
  margin-bottom: 6px;
  color: var(--navy);
}

.form input,
.form select,
.form textarea {
  width: 100%;
  border: 1px solid var(--line-strong);
  padding: 10px 12px;
  font: inherit;
  background: #fff;
  color: var(--ink);
}

.form textarea {
  min-height: 140px;
  resize: vertical;
}

.form input:focus,
.form select:focus,
.form textarea:focus {
  outline: 2px solid var(--accent-soft);
  border-color: var(--blue);
}

.form-note {
  font-size: 13px;
  color: var(--muted);
  margin-top: 12px;
}

.form-ok {
  display: none;
  border: 1px solid #b7d4c3;
  background: #f1f8f4;
  color: var(--ok);
  padding: 16px;
  margin-bottom: 16px;
}

.form-ok.is-show {
  display: block;
}

.form-error {
  display: none;
  border: 1px solid #dfb7b0;
  background: #fff5f3;
  color: #8a3b2e;
  padding: 16px;
  margin-bottom: 16px;
}

.form-error.is-show {
  display: block;
}

.form .btn:disabled {
  cursor: wait;
  opacity: 0.65;
}

.figure-inline {
  margin: 24px 0;
  border: 1px solid var(--line);
  background: var(--paper);
  padding: 16px;
}

.figure-inline img {
  width: 100%;
  max-width: 720px;
  margin: 0 auto;
}

.figure-caption {
  font-size: 12px;
  color: var(--muted);
  margin-top: 10px;
  text-align: center;
}

.callout-warn {
  border-left: 3px solid var(--warn);
  background: #fffaf3;
  padding: 16px 18px;
  margin-bottom: 24px;
}

.callout-warn h3 {
  font-size: 15px;
  margin-bottom: 6px;
}

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

.stub-actions {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-top: 24px;
}

@media (max-width: 960px) {
  .hero-inner,
  .grid-4,
  .chain,
  .split,
  .footer-grid,
  .cta-row,
  .demo-layout {
    grid-template-columns: 1fr;
  }

  .grid-3 {
    grid-template-columns: 1fr 1fr;
  }

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

@media (max-width: 800px) {
  .menu-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .header-cta {
    display: none;
  }

  .nav {
    display: none;
    position: absolute;
    top: var(--header-h);
    left: 0;
    right: 0;
    background: #fff;
    border-bottom: 1px solid var(--line);
    flex-direction: column;
    align-items: stretch;
    padding: 8px 12px 16px;
  }

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

  .nav-parent .dropdown {
    display: block;
    position: static;
    border: 0;
    padding: 0 0 0 12px;
  }

  .hero-inner,
  .page-hero {
    min-height: 0;
    padding: 36px 0;
  }

  .grid-2,
  .grid-3,
  .step {
    grid-template-columns: 1fr;
  }

  .module-nav {
    flex-direction: column;
  }

  .module-nav a,
  .module-nav .next {
    max-width: none;
    margin-left: 0;
    text-align: left;
  }

  .section {
    padding: 48px 0;
  }
}

@media print {
  .site-header,
  .site-footer,
  .header-cta,
  .menu-toggle,
  .hero-actions,
  .cta-band,
  .module-nav,
  .btn,
  .lang-switch,
  .demo-toolbar,
  .form {
    display: none !important;
  }

  body {
    background: #fff;
    color: #000;
  }

  .hero,
  .page-hero {
    background: #fff;
    color: #000;
  }

  .hero h1,
  .page-hero h1 {
    color: #000;
  }
}