:root {
  color-scheme: light;
  --ink: #17212b;
  --muted: #5c6773;
  --line: #dbe1e7;
  --surface: #ffffff;
  --soft: #f4f7f8;
  --brand: #1877d3;
  --accent: #f1783c;
  --green: #248a64;
  --warning: #fff6db;
  --warning-line: #d59a24;
  --max-width: 1120px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--ink);
  background: var(--surface);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
  line-height: 1.65;
}

a { color: inherit; }

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

.skip-link {
  position: fixed;
  left: 12px;
  top: -60px;
  z-index: 100;
  padding: 8px 12px;
  background: var(--ink);
  color: #fff;
}

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

.prelaunch {
  padding: 7px 16px;
  border-bottom: 1px solid var(--warning-line);
  background: var(--warning);
  color: #674900;
  font-size: 13px;
  text-align: center;
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  border-bottom: 1px solid rgba(219, 225, 231, 0.9);
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: blur(16px);
}

.nav-shell {
  width: min(calc(100% - 32px), var(--max-width));
  min-height: 64px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-size: 19px;
  font-weight: 750;
  text-decoration: none;
}

.brand-mark {
  width: 32px;
  height: 32px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 18px;
}

.site-nav { display: flex; align-items: center; gap: 24px; }

.site-nav a {
  color: var(--muted);
  font-size: 14px;
  font-weight: 600;
  text-decoration: none;
}

.site-nav a:hover,
.site-nav a[aria-current="page"] { color: var(--brand); }

.menu-toggle {
  width: 42px;
  height: 42px;
  display: none;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  color: var(--ink);
  font-size: 20px;
}

.hero {
  min-height: 760px;
  padding: 84px 24px 56px;
  overflow: hidden;
  border-bottom: 1px solid var(--line);
  background:
    linear-gradient(rgba(255, 255, 255, 0.9), rgba(244, 247, 248, 0.96)),
    url("app-home.png") center 38% / cover no-repeat;
  text-align: center;
}

.hero-copy { width: min(760px, 100%); margin: 0 auto; }

.eyebrow {
  margin: 0 0 12px;
  color: var(--brand);
  font-size: 13px;
  font-weight: 750;
  text-transform: uppercase;
}

h1,
h2,
h3 { margin: 0; line-height: 1.2; letter-spacing: 0; }

h1 { font-size: clamp(42px, 7vw, 72px); }

.hero-lead {
  max-width: 660px;
  margin: 20px auto 0;
  color: var(--muted);
  font-size: 19px;
}

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

.button {
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0 18px;
  border: 1px solid var(--ink);
  border-radius: 6px;
  background: var(--ink);
  color: #fff;
  font-weight: 700;
  text-decoration: none;
}

.button.secondary { background: transparent; color: var(--ink); }

.product-stage {
  width: min(820px, 92vw);
  margin: 52px auto -210px;
  padding: 9px;
  border: 2px solid #111820;
  border-radius: 22px;
  background: #111820;
  box-shadow: 0 24px 60px rgba(23, 33, 43, 0.22);
}

.product-stage img {
  width: 100%;
  aspect-ratio: 2622 / 1206;
  border-radius: 14px;
  object-fit: cover;
  background: #eef2f4;
}

.section { padding: 88px 24px; }

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

.section-inner { width: min(100%, var(--max-width)); margin: 0 auto; }

.section-heading { max-width: 680px; margin-bottom: 44px; }

.section-heading h2 { font-size: clamp(30px, 4vw, 44px); }

.section-heading p { margin: 14px 0 0; color: var(--muted); }

.feature-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 36px;
}

.feature { border-top: 3px solid var(--brand); padding-top: 20px; }
.feature:nth-child(2) { border-color: var(--accent); }
.feature:nth-child(3) { border-color: var(--green); }
.feature h3 { font-size: 20px; }
.feature p { margin: 10px 0 0; color: var(--muted); }

.trust-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: start;
}

.fact-list { margin: 0; padding: 0; list-style: none; }

.fact-list li {
  padding: 18px 0;
  border-bottom: 1px solid var(--line);
}

.fact-list strong { display: block; margin-bottom: 4px; }

.page-hero {
  padding: 82px 24px 56px;
  border-bottom: 1px solid var(--line);
  background: var(--soft);
}

.page-hero-inner,
.legal-content { width: min(100%, 840px); margin: 0 auto; }

.page-hero h1 { font-size: clamp(36px, 6vw, 56px); }
.page-hero p { max-width: 700px; margin: 16px 0 0; color: var(--muted); }

.legal-content { padding: 64px 24px 88px; }
.legal-content h2 { margin-top: 42px; font-size: 24px; }
.legal-content h2:first-child { margin-top: 0; }
.legal-content p,
.legal-content li { color: #384550; }
.legal-content ul { padding-left: 22px; }

.contact-band {
  padding: 40px 24px;
  background: var(--ink);
  color: #fff;
}

.contact-band .section-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.contact-band p { margin: 6px 0 0; color: #c8d0d7; }
.contact-band a { color: #fff; }

.site-footer {
  padding: 30px 24px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 13px;
}

.footer-inner {
  width: min(100%, var(--max-width));
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
}

.footer-links { display: flex; gap: 18px; flex-wrap: wrap; }

@media (max-width: 760px) {
  .prelaunch { text-align: left; }
  .menu-toggle { display: grid; place-items: center; }
  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 64px;
    display: none;
    padding: 16px 24px 22px;
    border-bottom: 1px solid var(--line);
    background: #fff;
    flex-direction: column;
    align-items: stretch;
    gap: 14px;
  }
  .site-nav.is-open { display: flex; }
  .hero { min-height: 690px; padding-top: 64px; }
  .hero-lead { font-size: 17px; }
  .product-stage { margin-top: 38px; margin-bottom: -110px; }
  .section { padding: 68px 20px; }
  .feature-grid,
  .trust-grid { grid-template-columns: 1fr; gap: 34px; }
  .contact-band .section-inner { align-items: flex-start; flex-direction: column; }
  .page-hero { padding: 60px 20px 44px; }
  .legal-content { padding: 48px 20px 72px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}