:root {
  --blue: #12b5d5;
  --blue-dark: #087f9e;
  --orange: #ff6426;
  --green: #8ccd00;
  --yellow: #ffc400;
  --ink: #1f2a32;
  --muted: #5f6d78;
  --line: #d9e3ea;
  --soft: #f4f8fb;
  --panel: #ffffff;
  --shadow: 0 18px 45px rgba(24, 48, 67, 0.12);
  --radius: 8px;
  --max: 1160px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: "Microsoft YaHei", "PingFang SC", "Segoe UI", Arial, sans-serif;
  color: var(--ink);
  background: #ffffff;
  line-height: 1.65;
}

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

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

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(14px);
}

.nav {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  font-weight: 800;
  letter-spacing: 0;
}

.brand img {
  width: 42px;
  height: 42px;
}

.brand span {
  font-size: 18px;
}

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

.nav-links a {
  flex: 0 0 auto;
  padding: 10px 12px;
  border-radius: var(--radius);
  color: #33434f;
  font-size: 14px;
  font-weight: 700;
  white-space: nowrap;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  background: #ecf8fb;
  color: var(--blue-dark);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  min-height: 44px;
  padding: 0 18px;
  border: 0;
  border-radius: var(--radius);
  background: var(--blue-dark);
  color: #fff;
  font: 800 15px/1 "Microsoft YaHei", "Segoe UI", Arial, sans-serif;
  cursor: pointer;
  box-shadow: 0 10px 24px rgba(8, 127, 158, 0.24);
}

.btn:hover {
  background: #066d89;
}

.btn.secondary {
  background: #fff;
  color: var(--ink);
  border: 1px solid var(--line);
  box-shadow: none;
}

.btn.orange {
  background: var(--orange);
  box-shadow: 0 10px 24px rgba(255, 100, 38, 0.24);
}

.hero {
  position: relative;
  overflow: hidden;
  background:
    linear-gradient(90deg, rgba(18, 181, 213, 0.11), transparent 36%),
    linear-gradient(135deg, #fff 0%, #f7fbfd 62%, #eef7fa 100%);
}

.hero::before {
  content: "";
  position: absolute;
  inset: auto 0 0 0;
  height: 7px;
  background: linear-gradient(90deg, var(--orange) 0 25%, var(--blue) 25% 50%, var(--green) 50% 75%, var(--yellow) 75%);
}

.hero-inner {
  width: min(var(--max), calc(100% - 40px));
  margin: 0 auto;
  min-height: 620px;
  display: grid;
  grid-template-columns: 0.95fr 1.05fr;
  align-items: center;
  gap: 56px;
  padding: 72px 0 76px;
}

.hero h1,
.page-hero h1 {
  margin: 0;
  font-size: clamp(40px, 6vw, 72px);
  line-height: 1.02;
  letter-spacing: 0;
}

.hero p,
.page-hero p {
  margin: 22px 0 0;
  color: var(--muted);
  font-size: 18px;
  max-width: 620px;
}

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

.hero-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-top: 34px;
}

.fact {
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.82);
}

.fact strong {
  display: block;
  font-size: 20px;
  line-height: 1.1;
}

.fact span {
  display: block;
  margin-top: 6px;
  color: var(--muted);
  font-size: 13px;
}

.hero-visual {
  position: relative;
}

.hero-visual img {
  width: 100%;
  filter: drop-shadow(0 30px 45px rgba(31, 42, 50, 0.16));
}

.section {
  padding: 84px 0;
}

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

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

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

.section-head h2,
.content h2 {
  margin: 0;
  font-size: clamp(30px, 4vw, 46px);
  line-height: 1.08;
  letter-spacing: 0;
}

.section-head p {
  margin: 0;
  color: var(--muted);
  max-width: 520px;
}

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

.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 22px;
}

.card,
.review,
.download-card,
.step,
.faq-item {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.card {
  padding: 24px;
}

.icon-box {
  width: 46px;
  height: 46px;
  display: grid;
  place-items: center;
  border-radius: var(--radius);
  margin-bottom: 18px;
  color: #fff;
}

.icon-box.blue { background: var(--blue-dark); }
.icon-box.orange { background: var(--orange); }
.icon-box.green { background: #74ad00; }
.icon-box.yellow { background: #d49b00; }

.icon-box svg {
  width: 25px;
  height: 25px;
  stroke: currentColor;
  fill: none;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.card h3,
.review h3,
.download-card h3,
.step h3,
.faq-item h3 {
  margin: 0 0 10px;
  font-size: 20px;
  line-height: 1.25;
}

.card p,
.review p,
.download-card p,
.step p,
.faq-item p,
.content p,
.content li {
  color: var(--muted);
}

.split {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 54px;
}

.media-frame {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: #fff;
  box-shadow: var(--shadow);
}

.scenario-list {
  display: grid;
  gap: 14px;
}

.scenario-row {
  display: grid;
  grid-template-columns: 10px 1fr;
  gap: 14px;
  align-items: start;
}

.scenario-row::before {
  content: "";
  width: 10px;
  height: 38px;
  border-radius: 8px;
  background: var(--blue);
  margin-top: 5px;
}

.scenario-row:nth-child(2)::before { background: var(--orange); }
.scenario-row:nth-child(3)::before { background: var(--green); }
.scenario-row:nth-child(4)::before { background: var(--yellow); }

.scenario-row strong {
  display: block;
  font-size: 18px;
}

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

.review {
  padding: 22px;
}

.review-top {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 14px;
}

.avatar {
  width: 42px;
  height: 42px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  color: #fff;
  font-weight: 900;
}

.avatar.a { background: var(--blue-dark); }
.avatar.b { background: var(--orange); }
.avatar.c { background: #74ad00; }

.quote {
  margin: 0;
  font-size: 15px;
}

.page-hero {
  background: linear-gradient(135deg, #eef8fb 0%, #ffffff 58%, #fff7d1 100%);
  border-bottom: 1px solid var(--line);
}

.page-hero .wrap {
  padding: 76px 0 70px;
}

.content {
  max-width: 860px;
}

.feature-list,
.download-list,
.source-list {
  padding-left: 20px;
}

.step {
  padding: 24px;
  position: relative;
}

.step-num {
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--ink);
  color: #fff;
  font-weight: 800;
  margin-bottom: 16px;
}

.download-card {
  padding: 26px;
}

.download-meta {
  display: grid;
  gap: 10px;
  margin: 18px 0 24px;
  color: var(--muted);
}

.download-meta div {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  border-bottom: 1px solid var(--line);
  padding-bottom: 10px;
}

.download-meta strong {
  color: var(--ink);
}

.faq-list {
  display: grid;
  gap: 14px;
}

.faq-item {
  padding: 22px 24px;
}

.source-note {
  margin-top: 28px;
  padding: 18px 20px;
  border-left: 4px solid var(--blue-dark);
  background: #eef8fb;
  color: #40515d;
}

.site-footer {
  background: #17222a;
  color: #d8e5ec;
  padding: 46px 0;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 28px;
}

.site-footer a {
  color: #d8e5ec;
}

.footer-links {
  display: grid;
  gap: 8px;
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
  background: rgba(10, 22, 30, 0.58);
}

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

.download-modal {
  width: min(720px, 100%);
  max-height: min(720px, calc(100vh - 40px));
  overflow: auto;
  border-radius: var(--radius);
  background: #fff;
  box-shadow: 0 28px 80px rgba(0, 0, 0, 0.26);
}

.modal-head {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 18px;
  padding: 24px 26px 16px;
  border-bottom: 1px solid var(--line);
}

.modal-head h2 {
  margin: 0;
  font-size: 26px;
}

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

.qr-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
  padding: 24px 26px 28px;
}

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

.qr-card img {
  width: 184px;
  height: 184px;
  margin: 0 auto 14px;
}

.qr-card strong {
  display: block;
  font-size: 18px;
}

.qr-card span {
  display: block;
  color: var(--muted);
  font-size: 13px;
  margin-top: 5px;
}

.skip-link {
  position: absolute;
  left: -999px;
  top: 10px;
  background: #fff;
  color: var(--ink);
  padding: 8px 10px;
  border: 1px solid var(--line);
}

.skip-link:focus {
  left: 10px;
  z-index: 200;
}

@media (max-width: 900px) {
  .nav {
    align-items: flex-start;
    flex-direction: column;
    padding: 14px 0;
  }

  .nav-links {
    width: 100%;
    overflow-x: auto;
    padding-bottom: 2px;
  }

  .hero-inner,
  .split,
  .grid-2,
  .footer-grid {
    grid-template-columns: 1fr;
  }

  .hero-inner {
    min-height: auto;
    padding-top: 46px;
  }

  .hero-visual {
    order: -1;
  }

  .section-head {
    align-items: flex-start;
    flex-direction: column;
  }

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

@media (max-width: 620px) {
  .wrap,
  .nav,
  .hero-inner {
    width: min(100% - 28px, var(--max));
  }

  .hero h1,
  .page-hero h1 {
    font-size: 40px;
  }

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

  .hero-actions .btn {
    width: 100%;
  }

  .section {
    padding: 58px 0;
  }
}