:root {
  --ink: #131722;
  --ink-2: #1d2430;
  --panel: #202938;
  --panel-2: #263244;
  --line: #344257;
  --text: #f4f7fb;
  --muted: #aeb8c6;
  --soft: #dce5ef;
  --blue: #1e93d9;
  --blue-2: #57b8ef;
  --red: #ff253a;
  --green: #49d889;
  --paper: #f5f8fb;
  --paper-2: #eaf1f7;
  --shadow: 0 24px 70px rgba(5, 9, 18, .28);
  --radius: 8px;
  color-scheme: dark;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Noto Sans SC", "Microsoft YaHei", "Segoe UI", Arial, sans-serif;
  background: var(--ink);
  color: var(--text);
  line-height: 1.75;
}

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

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(19, 23, 34, .9);
  border-bottom: 1px solid rgba(255,255,255,.08);
  backdrop-filter: blur(14px);
}

.nav {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
  min-width: 170px;
}

.brand img {
  width: 174px;
  height: auto;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-links a {
  padding: 10px 12px;
  border-radius: 6px;
  color: #d8e0eb;
  font-size: 15px;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  color: var(--text);
  background: rgba(255,255,255,.08);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.menu-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border: 1px solid rgba(255,255,255,.14);
  border-radius: 6px;
  background: transparent;
  color: var(--text);
}

.menu-toggle span {
  display: block;
  width: 18px;
  height: 2px;
  margin: 4px auto;
  background: currentColor;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 11px 18px;
  border: 1px solid transparent;
  border-radius: 6px;
  font-weight: 700;
  cursor: pointer;
  transition: transform .18s ease, border-color .18s ease, background .18s ease;
}

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

.btn-primary {
  background: var(--blue);
  color: #f8fbff;
  box-shadow: 0 12px 30px rgba(30, 147, 217, .28);
}

.btn-primary:hover {
  background: #2ba5ec;
}

.btn-ghost {
  color: var(--text);
  border-color: rgba(255,255,255,.18);
  background: rgba(255,255,255,.04);
}

.btn-light {
  color: #102033;
  background: var(--paper);
}

.hero {
  position: relative;
  overflow: hidden;
  padding: clamp(58px, 8vw, 104px) 0 42px;
  background:
    linear-gradient(135deg, rgba(30,147,217,.22), transparent 42%),
    radial-gradient(circle at 90% 16%, rgba(255,37,58,.18), transparent 26%),
    var(--ink);
}

.hero::after {
  content: "";
  position: absolute;
  inset: auto 0 0;
  height: 170px;
  background: linear-gradient(180deg, transparent, var(--ink));
  pointer-events: none;
}

.wrap {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
}

.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(420px, 1.08fr);
  align-items: center;
  gap: clamp(34px, 5vw, 72px);
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  color: #bfe5ff;
  font-weight: 700;
  margin-bottom: 16px;
}

.eyebrow::before {
  content: "";
  width: 10px;
  height: 10px;
  border-radius: 2px;
  background: var(--blue);
}

h1,
h2,
h3 {
  margin: 0;
  line-height: 1.12;
  letter-spacing: 0;
}

h1 {
  max-width: 900px;
  font-size: clamp(42px, 6vw, 58px);
}

h2 {
  font-size: clamp(30px, 4.2vw, 54px);
}

h3 {
  font-size: clamp(21px, 2vw, 28px);
}

.hero-copy {
  max-width: 660px;
  margin-top: 20px;
  font-size: 18px;
}

.hero-actions,
.section-actions {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.hero-panel {
  position: relative;
}

.hero-shot {
  border: 1px solid rgba(255,255,255,.16);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  background: var(--panel);
}

.hero-note {
  position: absolute;
  left: -22px;
  bottom: 26px;
  width: min(260px, 64%);
  padding: 14px 16px;
  border: 1px solid rgba(255,255,255,.14);
  border-radius: var(--radius);
  background: rgba(29, 36, 48, .94);
  box-shadow: 0 18px 40px rgba(0,0,0,.28);
}

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

.stat-strip {
  position: relative;
  z-index: 2;
  margin-top: 34px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border: 1px solid rgba(255,255,255,.12);
  border-radius: var(--radius);
  background: rgba(32, 41, 56, .72);
}

.stat {
  padding: 18px 20px;
  border-right: 1px solid rgba(255,255,255,.1);
}

.stat:last-child {
  border-right: 0;
}

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

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

.section {
  padding: clamp(58px, 8vw, 104px) 0;
}

.section-light {
  background: var(--paper);
  color: #172235;
}

.section-light p,
.section-light .section-lead,
.section-light .muted {
  color: #566579;
}

.section-head {
  display: flex;
  justify-content: space-between;
  gap: 28px;
  align-items: flex-start;
  margin-bottom: 34px;
}

.section-lead {
  max-width: 620px;
  font-size: 17px;
}

.feature-band {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: clamp(28px, 5vw, 66px);
  align-items: center;
  padding: 34px 0;
  border-top: 1px solid rgba(255,255,255,.1);
}

.section-light .feature-band {
  border-top-color: rgba(20,35,55,.12);
}

.feature-media {
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--panel);
  border: 1px solid rgba(255,255,255,.12);
}

.section-light .feature-media {
  border-color: rgba(20,35,55,.1);
  box-shadow: 0 20px 50px rgba(31,50,73,.12);
}

.tag-row {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 18px 0 0;
}

.tag {
  display: inline-flex;
  min-height: 30px;
  align-items: center;
  border: 1px solid rgba(255,255,255,.15);
  border-radius: 6px;
  padding: 3px 10px;
  color: #d9e8f7;
  background: rgba(255,255,255,.04);
  font-size: 13px;
}

.section-light .tag {
  color: #223348;
  border-color: rgba(30,147,217,.25);
  background: rgba(30,147,217,.08);
}

.scenario-grid,
.review-grid,
.download-grid,
.resource-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 18px;
}

.tile {
  padding: 24px;
  border: 1px solid rgba(255,255,255,.11);
  border-radius: var(--radius);
  background: var(--panel);
}

.section-light .tile {
  background: #fbfdff;
  border-color: rgba(20,35,55,.1);
  box-shadow: 0 12px 34px rgba(29, 51, 76, .08);
}

.tile h3 {
  margin-bottom: 10px;
}

.tile .mark {
  width: 42px;
  height: 42px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 6px;
  margin-bottom: 18px;
  background: rgba(30,147,217,.15);
  color: #9bd8ff;
  font-weight: 900;
}

.section-light .tile .mark {
  color: #0d70ad;
}

.review {
  min-height: 230px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.review blockquote {
  margin: 0;
  color: inherit;
  font-size: 17px;
}

.review cite {
  margin-top: 20px;
  color: var(--muted);
  font-style: normal;
}

.cta-band {
  padding: 54px;
  border-radius: var(--radius);
  background:
    linear-gradient(120deg, rgba(30,147,217,.96), rgba(28,56,84,.96)),
    var(--blue);
  color: #f8fbff;
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 24px;
  align-items: center;
}

.cta-band p {
  color: rgba(248,251,255,.82);
  max-width: 660px;
  margin-top: 10px;
}

.page-hero {
  padding: clamp(56px, 8vw, 96px) 0;
  background:
    linear-gradient(135deg, rgba(30,147,217,.18), transparent 48%),
    var(--ink);
}

.page-hero p {
  max-width: 760px;
  margin-top: 18px;
  font-size: 18px;
}

.steps {
  counter-reset: step;
  display: grid;
  gap: 14px;
}

.step {
  counter-increment: step;
  display: grid;
  grid-template-columns: 48px 1fr;
  gap: 16px;
  align-items: start;
  padding: 20px;
  border-radius: var(--radius);
  background: #fbfdff;
  border: 1px solid rgba(20,35,55,.1);
}

.step::before {
  content: counter(step);
  width: 44px;
  height: 44px;
  border-radius: 6px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: #203348;
  color: #f5fbff;
  font-weight: 800;
}

.download-card {
  display: flex;
  flex-direction: column;
  min-height: 310px;
}

.download-card .btn {
  margin-top: auto;
}

.meta-list {
  display: grid;
  gap: 10px;
  margin: 18px 0 24px;
}

.meta-list div {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(20,35,55,.1);
  color: #566579;
}

.meta-list strong {
  color: #172235;
}

.source-list {
  margin: 20px 0 0;
  padding-left: 20px;
  color: #566579;
}

.source-list a {
  color: #0d70ad;
  text-decoration: underline;
  text-underline-offset: 3px;
}

.site-footer {
  background: #10141d;
  border-top: 1px solid rgba(255,255,255,.08);
  padding: 42px 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.1fr .8fr;
  gap: 50px;
}

.footer-grid img {
  width: 170px;
  margin-bottom: 14px;
}

.footer-grid h3 {
  font-size: 16px;
  margin-bottom: 12px;
}

.footer-grid a {
  display: block;
  color: var(--muted);
  margin: 6px 0;
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  z-index: 60;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(7, 10, 16, .72);
}

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

.modal {
  width: min(680px, 100%);
  border-radius: var(--radius);
  background: var(--paper);
  color: #172235;
  box-shadow: var(--shadow);
  overflow: hidden;
}

.modal-head {
  display: flex;
  justify-content: space-between;
  gap: 18px;
  padding: 24px 26px;
  background: #fff;
  color: var(--ink);
}

.modal-head p {
  color: #b7c4d1;
}

.modal-close {
  width: 40px;
  height: 40px;
  border: 1px solid rgba(255,255,255,.16);
  border-radius: 6px;
  background: transparent;
  color: var(--text);
  cursor: pointer;
  font-size: 24px;
  line-height: 1;
}

.qr-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  padding: 24px 26px 12px;
}

.qr-card {
  border: 1px solid rgba(20,35,55,.12);
  border-radius: var(--radius);
  padding: 18px;
  background: #fbfdff;
  text-align: center;
}

.qr-card img {
  width: 160px;
  height: 160px;
  margin: 0 auto 12px;
}

.qr-card h3 {
  font-size: 18px;
  margin-bottom: 4px;
}

.modal-foot {
  padding: 0 26px 24px;
  color: #566579;
  font-size: 14px;
}

.skip-link {
  position: absolute;
  top: -50px;
  left: 14px;
  z-index: 100;
  padding: 8px 12px;
  background: var(--blue);
  color: #fff;
  border-radius: 6px;
}

.skip-link:focus {
  top: 12px;
}

@media (max-width: 920px) {
  .nav {
    min-height: 66px;
  }

  .menu-toggle {
    display: inline-block;
  }

  .nav-links {
    position: absolute;
    left: 16px;
    right: 16px;
    top: 66px;
    display: none;
    flex-direction: column;
    align-items: stretch;
    padding: 12px;
    background: #172033;
    border: 1px solid rgba(255,255,255,.12);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
  }

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

  .nav-actions .btn {
    display: none;
  }

  .hero-grid,
  .feature-band,
  .cta-band {
    grid-template-columns: 1fr;
  }

  .hero-note {
    position: static;
    width: auto;
    margin-top: 12px;
  }

  .stat-strip,
  .scenario-grid,
  .review-grid,
  .download-grid,
  .resource-grid,
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 640px) {
  .brand img {
    width: 148px;
  }

  .hero {
    padding-top: 44px;
  }

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

  .stat-strip,
  .scenario-grid,
  .review-grid,
  .download-grid,
  .resource-grid,
  .footer-grid,
  .qr-grid {
    grid-template-columns: 1fr;
  }

  .section-head {
    display: block;
  }

  .cta-band {
    padding: 28px;
  }

  .stat {
    border-right: 0;
    border-bottom: 1px solid rgba(255,255,255,.1);
  }

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