:root {
  --ink: #172033;
  --muted: #5d6878;
  --brand: #075eb8;
  --brand-dark: #08447f;
  --accent: #0f766e;
  --warm: #fff7df;
  --line: #dce4ee;
  --soft: #f4f8fc;
  --white: #ffffff;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--white);
  font-family: "Microsoft YaHei", "PingFang SC", Arial, sans-serif;
  line-height: 1.75;
}

a { color: var(--brand-dark); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap {
  width: min(1120px, calc(100% - 32px));
  margin: 0 auto;
}

.topbar {
  min-height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  border-bottom: 1px solid var(--line);
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-weight: 800;
}

.brand img {
  width: 32px;
  height: 32px;
  image-rendering: auto;
}

.nav { display: flex; flex-wrap: wrap; gap: 18px; font-size: 14px; }

.hero {
  padding: 58px 0 48px;
  background: #eef5fb;
  border-bottom: 1px solid var(--line);
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(300px, .65fr);
  gap: 42px;
  align-items: center;
}

.hero-grid > * { min-width: 0; }

.kicker { color: var(--accent); font-weight: 800; }

h1 {
  margin: 10px 0 16px;
  font-size: 44px;
  line-height: 1.22;
  overflow-wrap: anywhere;
}

.lead { margin: 0; max-width: 760px; color: var(--muted); font-size: 18px; overflow-wrap: anywhere; }

.format-list {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 20px 0;
}

.format-list span {
  padding: 5px 11px;
  border: 1px solid #b9ccdf;
  background: var(--white);
  color: var(--brand-dark);
  font-size: 13px;
  font-weight: 700;
}

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

.button {
  display: inline-flex;
  min-height: 44px;
  align-items: center;
  justify-content: center;
  padding: 10px 18px;
  border: 1px solid var(--brand);
  border-radius: 6px;
  background: var(--brand);
  color: var(--white);
  font-weight: 800;
}

.button:hover { color: var(--white); text-decoration: none; background: var(--brand-dark); }
.button.secondary { background: var(--white); color: var(--brand-dark); }
.button.secondary:hover { color: var(--brand-dark); background: #f7fafc; }

.product-panel {
  padding: 24px;
  border: 1px solid #b8cadc;
  border-radius: 8px;
  background: var(--white);
  box-shadow: 0 14px 30px rgba(31, 61, 92, .10);
}

.product-icon {
  width: 72px;
  height: 72px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--soft);
  image-rendering: auto;
}

.product-panel h2 { margin: 14px 0 8px; font-size: 21px; line-height: 1.45; overflow-wrap: anywhere; }
.version { color: var(--accent); font-weight: 800; }

.facts { margin: 16px 0 0; padding: 0; list-style: none; }
.facts li { padding: 7px 0; border-top: 1px solid var(--line); color: var(--muted); font-size: 14px; }
.facts strong { color: var(--ink); }

.section { padding: 46px 0; }
.section.alt { background: var(--soft); border: 1px solid var(--line); border-width: 1px 0; }
.section h2 { margin: 0 0 12px; font-size: 30px; line-height: 1.35; }
.section-intro { max-width: 760px; margin: 0 0 24px; color: var(--muted); }

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

.feature, .step, .support-box {
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--white);
}

.feature h3, .step h3, .support-box h3 { margin: 0 0 8px; font-size: 19px; }
.feature p, .step p, .support-box p { margin: 0; color: var(--muted); }

.step-number {
  display: inline-flex;
  width: 30px;
  height: 30px;
  align-items: center;
  justify-content: center;
  margin-bottom: 12px;
  border-radius: 50%;
  background: var(--brand);
  color: var(--white);
  font-weight: 800;
}

.sample-table { width: 100%; border-collapse: collapse; background: var(--white); }
.sample-table th, .sample-table td { padding: 12px 14px; border: 1px solid var(--line); text-align: left; }
.sample-table th { background: #e9f1f8; }

.notice {
  margin-top: 22px;
  padding: 14px 16px;
  border-left: 4px solid var(--accent);
  background: #eef9f7;
  color: #345c58;
}

.download-box {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 24px;
  align-items: center;
  padding: 26px;
  border: 1px solid #b8cadc;
  border-radius: 8px;
  background: #eef5fb;
}

.download-box h2 { margin-bottom: 8px; }
.download-box p { margin: 0; color: var(--muted); }
.hash { margin-top: 12px; overflow-wrap: anywhere; color: var(--muted); font-family: Consolas, monospace; font-size: 12px; }

.faq details { border-top: 1px solid var(--line); padding: 15px 0; }
.faq details:last-child { border-bottom: 1px solid var(--line); }
.faq summary { cursor: pointer; font-weight: 800; }
.faq p { margin: 8px 0 0; color: var(--muted); }

.footer { padding: 28px 0 42px; border-top: 1px solid var(--line); color: var(--muted); font-size: 14px; }

@media (max-width: 820px) {
  .topbar { align-items: flex-start; flex-direction: column; padding: 14px 0; }
  .hero { padding: 38px 0; }
  .hero-grid, .download-box { grid-template-columns: 1fr; }
  .feature-grid, .steps, .support-grid { grid-template-columns: 1fr; }
  h1 { font-size: 34px; }
}

@media (max-width: 480px) {
  .wrap { width: min(100% - 24px, 1120px); }
  h1 { font-size: 29px; }
  .section h2 { font-size: 25px; }
  .button { width: 100%; }
  .sample-table { font-size: 13px; }
  .sample-table th, .sample-table td { padding: 9px 8px; }
}