:root {
  --bg: #f6f7f9;
  --surface: #ffffff;
  --surface-soft: #f2f4f7;
  --text: #1f2933;
  --muted: #667085;
  --line: #e4e7ec;
  --line-strong: #cfd6e0;
  --orange: #ff6a00;
  --orange-dark: #e85f00;
  --blue: #0ea5e9;
  --slate: #263445;
  --shadow: 0 22px 70px rgba(31, 41, 51, 0.10);
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.86), rgba(246, 247, 249, 0.94) 420px), var(--bg);
  color: var(--text);
  font-family: "Microsoft YaHei", "PingFang SC", "Segoe UI", Arial, sans-serif;
  letter-spacing: 0;
}
a { color: inherit; text-decoration: none; }
svg { fill: none; stroke: currentColor; stroke-linecap: round; stroke-linejoin: round; stroke-width: 2; }

.site-header {
  align-items: center;
  display: grid;
  gap: 18px;
  grid-template-columns: 1fr auto 148px;
  margin: 0 auto;
  max-width: 1120px;
  padding: 22px 24px 0;
}
.brand, .header-download, .primary-action, .secondary-action { align-items: center; display: inline-flex; }
.brand { gap: 10px; font-size: 15px; font-weight: 800; }
.brand img { border-radius: 8px; box-shadow: 0 10px 24px rgba(255, 106, 0, 0.18); height: 34px; width: 34px; }
.nav-links { align-items: center; color: #526071; display: flex; font-size: 14px; gap: 24px; }
.nav-links a:hover { color: var(--orange); }
.header-download, .primary-action {
  background: var(--orange);
  border-radius: 6px;
  color: #fff;
  font-size: 14px;
  font-weight: 800;
  gap: 8px;
  justify-content: center;
  min-height: 42px;
  padding: 0 16px;
}
.header-download:hover, .primary-action:hover { background: var(--orange-dark); }
.header-download svg, .primary-action svg { height: 18px; width: 18px; }

.hero {
  align-items: center;
  display: grid;
  gap: 54px;
  grid-template-columns: minmax(0, 1fr) 384px;
  margin: 0 auto;
  max-width: 1120px;
  min-height: 560px;
  padding: 54px 24px 56px;
}
.hero-copy h1 { font-size: clamp(42px, 6vw, 72px); letter-spacing: 0; line-height: 1.05; margin: 0; max-width: 760px; }
.hero-copy p { color: var(--muted); font-size: 18px; line-height: 1.9; margin: 24px 0 0; max-width: 680px; }
.hero-actions { display: flex; flex-wrap: wrap; gap: 12px; margin-top: 34px; }
.primary-action { min-height: 48px; padding: 0 20px; }
.secondary-action { background: #e7eaf0; border-radius: 6px; color: var(--slate); font-size: 14px; font-weight: 800; justify-content: center; min-height: 48px; padding: 0 18px; }
.secondary-action:hover { background: #d7dce5; }

.product-preview { background: var(--surface); border: 1px solid var(--line); border-radius: 8px; box-shadow: var(--shadow); padding: 18px; position: relative; }
.product-preview::before { background: linear-gradient(90deg, var(--orange), var(--blue)); border-radius: 999px; content: ""; height: 4px; left: 18px; position: absolute; right: 18px; top: 18px; }
.preview-header { align-items: center; display: flex; gap: 12px; padding-top: 18px; }
.preview-header img { border-radius: 8px; height: 44px; width: 44px; }
.preview-header strong, .preview-header span { display: block; }
.preview-header strong { font-size: 18px; line-height: 1.3; }
.preview-header span { color: var(--muted); font-size: 13px; margin-top: 4px; }
.field-row { align-items: center; border: 1px solid var(--line); border-radius: 8px; display: flex; justify-content: space-between; margin-top: 12px; min-height: 48px; padding: 0 14px; }
.field-row:first-of-type { margin-top: 20px; }
.field-row span, .progress-top span, .preview-log { color: var(--muted); font-size: 13px; }
.field-row strong, .progress-top strong { color: var(--text); font-size: 13px; }
.progress-top { align-items: center; display: flex; justify-content: space-between; margin-top: 20px; }
.progress-track { background: #e8edf5; border-radius: 999px; height: 10px; margin-top: 12px; overflow: hidden; }
.progress-track span { background: linear-gradient(90deg, var(--orange), var(--blue)); display: block; height: 100%; width: 76%; }
.preview-log { border-top: 1px solid #edf0f4; line-height: 1.6; list-style: none; margin: 18px 0 0; padding: 12px 0 0; }
.preview-log li { padding: 4px 0 4px 18px; position: relative; }
.preview-log li::before { background: var(--blue); border-radius: 999px; content: ""; height: 6px; left: 0; position: absolute; top: 13px; width: 6px; }

.section-block { margin: 0 auto; max-width: 1120px; padding: 84px 24px; }
.section-heading { max-width: 720px; }
.section-heading h2, .security-band h2 { font-size: clamp(30px, 4vw, 46px); line-height: 1.16; margin: 0; }
.section-heading p, .security-band p { color: var(--muted); font-size: 16px; line-height: 1.8; margin: 16px 0 0; }
.feature-grid, .seo-grid { display: grid; gap: 16px; grid-template-columns: repeat(3, 1fr); margin-top: 34px; }
.feature-card, .seo-grid article, .faq-list article { background: var(--surface); border: 1px solid var(--line); border-radius: 8px; padding: 24px; }
.feature-card { min-height: 208px; }
.feature-mark { border-radius: 999px; display: block; height: 10px; width: 44px; }
.feature-mark.orange { background: var(--orange); }
.feature-mark.blue { background: var(--blue); }
.feature-mark.slate { background: var(--slate); }
.feature-card h3, .seo-grid h3, .faq-list h3 { font-size: 20px; margin: 24px 0 0; }
.seo-grid h3, .faq-list h3 { margin-top: 0; }
.feature-card p, .seo-grid p, .faq-list p { color: var(--muted); font-size: 14px; line-height: 1.8; margin: 12px 0 0; }

.seo-section { border-top: 1px solid var(--line); }
.detail-layout { display: grid; gap: 42px; grid-template-columns: minmax(0, 0.85fr) minmax(320px, 1fr); padding-top: 56px; }
.field-list { display: grid; gap: 10px; grid-template-columns: repeat(3, 1fr); }
.field-list span { background: var(--surface); border: 1px solid var(--line); border-radius: 6px; color: #475467; font-size: 13px; font-weight: 700; min-height: 42px; padding: 12px 14px; }
.install-layout { display: grid; gap: 48px; grid-template-columns: minmax(0, 0.9fr) minmax(320px, 1fr); }
.steps { display: grid; gap: 12px; list-style: none; margin: 0; padding: 0; }
.steps li { align-items: center; background: var(--surface); border: 1px solid var(--line); border-radius: 8px; display: grid; gap: 16px; grid-template-columns: 58px 1fr; min-height: 86px; padding: 18px; }
.steps span { color: var(--orange); font-size: 18px; font-weight: 900; }
.steps p { color: #475467; font-size: 15px; line-height: 1.7; margin: 0; }
.faq-list { display: grid; gap: 14px; margin-top: 34px; }
.security-band { align-items: center; background: var(--slate); border-radius: 8px; color: #fff; display: grid; gap: 32px; grid-template-columns: 1fr auto; margin-bottom: 52px; padding: 44px; }
.security-band p { color: #cfd6e0; max-width: 720px; }
.site-footer { align-items: center; border-top: 1px solid var(--line); color: var(--muted); display: flex; font-size: 13px; justify-content: space-between; margin: 0 auto; max-width: 1120px; padding: 28px 24px 42px; }

@media (max-width: 860px) {
  .site-header { grid-template-columns: 1fr auto; }
  .nav-links { display: none; }
  .header-download { min-width: 136px; }
  .hero, .install-layout, .security-band, .detail-layout { grid-template-columns: 1fr; }
  .hero { gap: 38px; min-height: auto; padding-top: 54px; }
  .feature-grid, .seo-grid { grid-template-columns: 1fr; }
  .field-list { grid-template-columns: repeat(2, 1fr); }
  .security-band { padding: 32px 24px; }
}
@media (max-width: 560px) {
  .site-header { padding: 16px 16px 0; }
  .brand span { display: none; }
  .header-download { font-size: 13px; min-height: 40px; padding: 0 12px; }
  .hero, .section-block { padding-left: 16px; padding-right: 16px; }
  .hero-copy h1 { font-size: 40px; }
  .hero-copy p { font-size: 16px; }
  .hero-actions, .primary-action, .secondary-action { width: 100%; }
  .product-preview, .feature-card, .seo-grid article, .faq-list article, .steps li { padding: 18px; }
  .steps li, .field-list { grid-template-columns: 1fr; }
  .site-footer { align-items: flex-start; flex-direction: column; gap: 8px; padding-left: 16px; padding-right: 16px; }
}