:root {
  --bg: #ffffff;
  --bg-soft: #f6f7f9;
  --bg-card: #ffffff;
  --line: #e5e7eb;
  --line-strong: #d1d5db;
  --ink: #16181d;
  --ink-2: #4b5563;
  --ink-3: #8b929e;
  --brand: #1c4d8c;
  --brand-soft: #eaf1fa;
  --brand-ink: #14375f;
  --accent: #0f766e;
  --accent-soft: #e6f4f2;
  --radius: 10px;
  --radius-lg: 14px;
  --maxw: 1120px;
  --font: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, -apple-system, "Segoe UI", sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

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

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

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

.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 18px;
  font-weight: 600;
  letter-spacing: 0.2px;
}

.logo-mark {
  width: 30px;
  height: 29.51px;   /* viewBox 671x660 等比（logo.png 轮廓描摹） */
  flex: none;
  color: var(--brand);
  display: grid;
  place-items: center;
}

.logo-mark svg {
  width: 100%;
  height: 100%;
  display: block;
}

.nav { display: flex; align-items: center; gap: 30px; }

.nav a {
  font-size: 15px;
  color: var(--ink-2);
  transition: color 0.18s;
}

.nav a:hover { color: var(--brand); }

.nav .btn-nav {
  padding: 8px 18px;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  color: var(--ink);
  font-size: 14px;
}

.nav .btn-nav:hover { border-color: var(--brand); color: var(--brand); }

.menu-toggle {
  display: none;
  background: none;
  border: 1px solid var(--line-strong);
  border-radius: 8px;
  width: 38px;
  height: 34px;
  cursor: pointer;
  color: var(--ink-2);
  font-size: 16px;
  line-height: 1;
}

/* ---------- hero ---------- */
.hero {
  padding: 92px 0 78px;
  background:
    radial-gradient(760px 380px at 82% -8%, var(--brand-soft) 0%, rgba(234, 241, 250, 0) 68%),
    var(--bg);
}

.hero-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 16px;
  max-width: 780px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  align-self: flex-start;
  padding: 5px 13px;
  background: var(--brand-soft);
  color: var(--brand-ink);
  border-radius: 100px;
  font-size: 13px;
  font-weight: 500;
}

.eyebrow::before {
  content: "";
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--brand);
}

h1 {
  font-size: 44px;
  line-height: 1.28;
  font-weight: 600;
  letter-spacing: -0.6px;
}

h1 .hl { color: var(--brand); }

.hero p.lead {
  font-size: 18px;
  color: var(--ink-2);
  max-width: 660px;
}

.hero-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  margin-top: 12px;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 26px;
  border-radius: 9px;
  font-size: 15px;
  font-weight: 500;
  transition: all 0.18s;
  cursor: pointer;
  border: 1px solid transparent;
}

.btn-primary { background: var(--brand); color: #fff; }
.btn-primary:hover { background: var(--brand-ink); }

.btn-ghost {
  background: transparent;
  border-color: var(--line-strong);
  color: var(--ink);
}
.btn-ghost:hover { border-color: var(--brand); color: var(--brand); }

/* ---------- section ---------- */
section { padding: 76px 0; }

.section-soft { background: var(--bg-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }

.section-head { max-width: 640px; margin-bottom: 44px; }

.section-head h2 {
  font-size: 29px;
  font-weight: 600;
  letter-spacing: -0.3px;
  margin-bottom: 12px;
}

.section-head p { color: var(--ink-2); font-size: 16px; }

/* ---------- capability cards ---------- */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(268px, 1fr));
  gap: 20px;
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 28px 26px;
  transition: border-color 0.18s, transform 0.18s;
}

.card:hover { border-color: var(--brand); transform: translateY(-2px); }

.card-icon {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  background: var(--brand-soft);
  color: var(--brand);
  display: grid;
  place-items: center;
  margin-bottom: 18px;
  font-size: 19px;
}

.card h3 { font-size: 17px; font-weight: 600; margin-bottom: 8px; }

.card p { font-size: 14.5px; color: var(--ink-2); line-height: 1.68; }

/* ---------- products ---------- */
.products {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 20px;
}

.product {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 26px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: border-color 0.18s, box-shadow 0.18s;
}

.product:hover { border-color: var(--line-strong); box-shadow: 0 4px 18px rgba(22, 24, 29, 0.05); }

.product-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.product h3 { font-size: 17px; font-weight: 600; }

.tag {
  font-size: 12px;
  padding: 3px 10px;
  border-radius: 100px;
  background: var(--bg-soft);
  color: var(--ink-3);
  border: 1px solid var(--line);
  white-space: nowrap;
}

.tag-live { background: var(--accent-soft); color: var(--accent); border-color: #bfe3dd; }

.product p { font-size: 14.5px; color: var(--ink-2); flex: 1; }

.product-link {
  font-size: 14px;
  color: var(--brand);
  font-weight: 500;
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.product-link::after { content: "→"; transition: transform 0.18s; }
.product:hover .product-link::after { transform: translateX(3px); }

/* ---------- steps ---------- */
.steps { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 20px; }

.step { padding-top: 22px; border-top: 2px solid var(--brand); }

.step-num {
  font-size: 13px;
  color: var(--brand);
  font-weight: 600;
  margin-bottom: 10px;
  letter-spacing: 0.5px;
}

.step h3 { font-size: 16px; font-weight: 600; margin-bottom: 8px; }
.step p { font-size: 14.5px; color: var(--ink-2); }

/* ---------- ai banner ---------- */
.ai-banner {
  background: linear-gradient(135deg, #14375f 0%, #1c4d8c 58%, #0f766e 100%);
  border-radius: var(--radius-lg);
  padding: 48px 46px;
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
  flex-wrap: wrap;
}

.ai-banner h2 { font-size: 26px; font-weight: 600; margin-bottom: 10px; letter-spacing: -0.3px; }

.ai-banner p { color: rgba(255, 255, 255, 0.82); font-size: 15.5px; max-width: 560px; }

.btn-light {
  background: #fff;
  color: var(--brand-ink);
  white-space: nowrap;
}
.btn-light:hover { background: rgba(255, 255, 255, 0.88); }

/* ---------- about ---------- */
.about-grid {
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 56px;
  align-items: start;
}

.about-copy p { color: var(--ink-2); margin-bottom: 16px; font-size: 15.5px; }

.facts { display: grid; gap: 14px; }

.fact {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 18px 20px;
}

.fact dt { font-size: 13px; color: var(--ink-3); margin-bottom: 4px; }
.fact dd { font-size: 15.5px; font-weight: 500; }

/* ---------- contact ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 20px;
}

.contact-item {
  background: var(--bg-card);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 26px;
}

.contact-item dt { font-size: 13px; color: var(--ink-3); margin-bottom: 8px; }
.contact-item dd { font-size: 16px; font-weight: 500; word-break: break-all; }
.contact-item dd a:hover { color: var(--brand); }

/* ---------- footer ---------- */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 40px 0 34px;
  background: var(--bg-soft);
}

.footer-grid {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 32px;
  flex-wrap: wrap;
}

.footer-brand { max-width: 340px; }

.footer-brand p { font-size: 13.5px; color: var(--ink-3); margin-top: 10px; line-height: 1.7; }

.footer-links { display: flex; gap: 60px; flex-wrap: wrap; }

.footer-col h4 { font-size: 13px; color: var(--ink-3); font-weight: 500; margin-bottom: 12px; }

.footer-col a { display: block; font-size: 14px; color: var(--ink-2); margin-bottom: 8px; }
.footer-col a:hover { color: var(--brand); }

.footer-bottom {
  margin-top: 34px;
  padding-top: 22px;
  border-top: 1px solid var(--line);
  font-size: 13px;
  color: var(--ink-3);
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}

/* ---------- responsive ---------- */
@media (max-width: 880px) {
  .about-grid { grid-template-columns: 1fr; gap: 34px; }
  h1 { font-size: 34px; }
  .hero { padding: 64px 0 56px; }
  section { padding: 58px 0; }
  .ai-banner { padding: 34px 28px; }
  .footer-links { gap: 36px; }
}

@media (max-width: 720px) {
  .nav { display: none; }
  .nav.open {
    display: flex;
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    background: #fff;
    border-bottom: 1px solid var(--line);
    padding: 8px 24px 18px;
  }
  .nav.open a { padding: 11px 0; border-bottom: 1px solid var(--line); }
  .nav.open .btn-nav { border: none; padding: 11px 0; }
  .menu-toggle { display: block; }
  h1 { font-size: 29px; }
  .section-head h2 { font-size: 24px; }
  .section-head { margin-bottom: 30px; }
}