:root {
  --brand: #1769aa;
  --brand-dark: #125387;
  --brand-soft: #e8f2fb;
  --accent: #f0a500;
  --ink: #101828;
  --muted: #5b6b7f;
  --line: #e3e9f0;
  --bg: #ffffff;
  --bg-alt: #f6f9fd;
  --card: #ffffff;
  --radius: 16px;
  --shadow: 0 12px 32px rgba(16, 24, 40, 0.08);
  --shadow-sm: 0 4px 12px rgba(16, 24, 40, 0.06);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: "PingFang SC", "Microsoft YaHei", "Segoe UI", system-ui, -apple-system, sans-serif;
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

img, svg { max-width: 100%; }
a { color: var(--brand); text-decoration: none; }
a:hover { color: var(--brand-dark); }
h1, h2, h3 { line-height: 1.25; margin: 0 0 12px; }
p { margin: 0 0 12px; }
code {
  font-family: ui-monospace, SFMono-Regular, Consolas, monospace;
  background: var(--brand-soft);
  color: var(--brand-dark);
  padding: 1px 6px;
  border-radius: 6px;
  font-size: 0.9em;
}

.wrap { width: min(1160px, 92vw); margin: 0 auto; }
.wrap.narrow { width: min(820px, 92vw); }
.muted { color: var(--muted); }
.small { font-size: 13px; }
.center { text-align: center; }

/* ---------- header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.86);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--line);
}
.header-inner {
  display: flex;
  align-items: center;
  gap: 24px;
  min-height: 68px;
}
.brand { display: flex; align-items: center; gap: 10px; color: var(--ink); font-weight: 700; }
.brand:hover { color: var(--ink); }
.brand-mark { width: 32px; height: 32px; flex: none; }
.brand-text { font-size: 17px; letter-spacing: 0.2px; }
.brand-text small { font-size: 12px; font-weight: 500; color: var(--muted); margin-left: 4px; }
.nav { display: flex; gap: 20px; margin-left: 8px; }
.nav a { color: var(--muted); font-size: 15px; font-weight: 500; }
.nav a:hover { color: var(--brand); }
.header-actions { margin-left: auto; display: flex; gap: 10px; }

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 10px 18px;
  border-radius: 10px;
  border: 1px solid transparent;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: background 0.18s ease, color 0.18s ease, border-color 0.18s ease, transform 0.18s ease;
  white-space: nowrap;
}
.btn-primary { background: var(--brand); color: #fff; }
.btn-primary:hover { background: var(--brand-dark); color: #fff; transform: translateY(-1px); }
.btn-outline { background: transparent; color: var(--brand); border-color: #bcd6ec; }
.btn-outline:hover { background: var(--brand-soft); color: var(--brand-dark); }
.btn-ghost { background: transparent; color: var(--muted); }
.btn-ghost:hover { color: var(--brand); background: var(--brand-soft); }
.btn-lg { padding: 13px 26px; font-size: 16px; border-radius: 12px; }
.btn[aria-disabled="true"] { opacity: 0.6; pointer-events: none; }

/* ---------- hero ---------- */
.hero {
  padding: 72px 0 84px;
  background:
    radial-gradient(1100px 420px at 12% -10%, #e8f2fb 0%, rgba(232, 242, 251, 0) 62%),
    linear-gradient(180deg, #fbfdff 0%, #ffffff 100%);
  border-bottom: 1px solid var(--line);
}
.hero-grid { display: grid; grid-template-columns: 1.05fr 0.95fr; gap: 56px; align-items: center; }
.eyebrow {
  display: inline-block;
  font-size: 13px;
  font-weight: 600;
  color: var(--brand);
  background: var(--brand-soft);
  border-radius: 999px;
  padding: 4px 12px;
  margin-bottom: 18px;
}
.hero h1 { font-size: clamp(32px, 4.4vw, 52px); letter-spacing: -0.5px; margin-bottom: 18px; }
.hero h1 .accent { color: var(--brand); }
.lead { font-size: 17px; color: #3f4d5f; max-width: 34em; }
.hero-actions { display: flex; gap: 12px; margin: 26px 0 20px; flex-wrap: wrap; }
.hero-points { display: flex; gap: 22px; list-style: none; padding: 0; margin: 0; color: var(--muted); font-size: 14px; }
.hero-points li { position: relative; padding-left: 20px; }
.hero-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  width: 10px;
  height: 10px;
  border-radius: 3px;
  background: var(--accent);
}

.hero-visual { position: relative; }
.shot-card {
  margin: 0;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 18px;
  box-shadow: var(--shadow);
  overflow: hidden;
}
.shot-card a { display: block; }
.shot-card img { display: block; width: 100%; height: auto; }
.shot-card figcaption {
  font-size: 13px;
  color: var(--muted);
  padding: 12px 16px;
  border-top: 1px solid var(--line);
  background: #fbfdff;
}
.shot-card figcaption b { color: var(--ink); }
.shots { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 24px; }

/* ---------- sections ---------- */
.section { padding: 72px 0; }
.section-alt { background: var(--bg-alt); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }
.section-title { font-size: clamp(24px, 2.8vw, 34px); letter-spacing: -0.3px; }
.section-sub { color: var(--muted); margin-bottom: 36px; max-width: 46em; }

.cards { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  transition: transform 0.18s ease, box-shadow 0.18s ease;
}
.card:hover { transform: translateY(-3px); box-shadow: var(--shadow); }
.card h3 { font-size: 18px; }
.card p { color: var(--muted); margin: 0; font-size: 15px; }
.card-icon {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  background: var(--brand-soft);
  color: var(--brand);
  display: grid;
  place-items: center;
  margin-bottom: 16px;
}
.card-icon svg { width: 24px; height: 24px; }

.steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; margin-bottom: 40px; }
.step {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px;
  box-shadow: var(--shadow-sm);
}
.step-no {
  display: inline-block;
  font-size: 13px;
  font-weight: 700;
  color: var(--brand);
  background: var(--brand-soft);
  border-radius: 8px;
  padding: 2px 10px;
  margin-bottom: 14px;
  letter-spacing: 1px;
}
.step h3 { font-size: 18px; }
.step p { color: var(--muted); margin: 0; }

.banner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  background: linear-gradient(120deg, #1769aa, #0d4d80);
  color: #fff;
  border-radius: 18px;
  padding: 30px 34px;
  box-shadow: var(--shadow);
}
.banner h3 { margin: 0 0 6px; font-size: 21px; }
.banner p { margin: 0; color: rgba(255, 255, 255, 0.86); }
.banner .btn-primary { background: #fff; color: var(--brand-dark); }
.banner .btn-primary:hover { background: #eef6fd; color: var(--brand-dark); }

/* ---------- download ---------- */
.download-card {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 28px;
  align-items: center;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px 30px;
  box-shadow: var(--shadow-sm);
}
.download-version { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin-bottom: 10px; }
.badge {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--brand-soft);
  color: var(--brand-dark);
  border-radius: 999px;
  padding: 4px 12px;
  font-size: 13px;
  font-weight: 700;
}
.download-actions { display: flex; flex-direction: column; gap: 10px; }
.download-actions .btn { width: 100%; }
.download-note { color: #3f4d5f; margin-bottom: 8px; }
.requirements {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin-top: 20px;
}
.requirements div {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.requirements strong { font-size: 13px; color: var(--muted); font-weight: 600; }
.requirements span { font-size: 15px; }

/* ---------- pricing ---------- */
.pricing { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 18px; margin-bottom: 22px; }
.price-card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  box-shadow: var(--shadow-sm);
  position: relative;
}
.price-card.featured { border-color: var(--brand); box-shadow: 0 14px 30px rgba(23, 105, 170, 0.16); }
.price-card.placeholder { color: var(--muted); text-align: center; grid-column: 1 / -1; }
.price-badge {
  position: absolute;
  top: -11px;
  right: 18px;
  background: var(--brand);
  color: #fff;
  font-size: 12px;
  font-weight: 700;
  border-radius: 999px;
  padding: 2px 10px;
}
.price-name { font-size: 17px; font-weight: 700; }
.price-desc { color: var(--muted); font-size: 14px; min-height: 40px; }
.price-value { font-size: 34px; font-weight: 800; letter-spacing: -1px; }
.price-value small { font-size: 15px; font-weight: 600; color: var(--muted); margin-right: 2px; }
.price-card .btn { margin-top: auto; }

/* ---------- faq ---------- */
.faq-item {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px 20px;
  margin-bottom: 12px;
  background: #fff;
}
.faq-item summary { cursor: pointer; font-weight: 600; font-size: 16px; list-style: none; }
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after { content: "+"; float: right; color: var(--brand); font-weight: 700; }
.faq-item[open] summary::after { content: "−"; }
.faq-item p { color: var(--muted); margin: 12px 0 0; }

/* ---------- contact ---------- */
.contact-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  background: var(--bg-alt);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 30px 32px;
}
.contact-card h2 { margin-bottom: 6px; }
.contact-card p { margin: 0; color: var(--muted); }
.contact-action { display: flex; flex-direction: column; gap: 8px; align-items: flex-end; }
.qq-label { font-size: 13px; color: var(--muted); }
.qq-number {
  font-family: ui-monospace, Consolas, monospace;
  font-size: 24px;
  font-weight: 700;
  color: var(--brand);
  background: #fff;
  border: 1px dashed #bcd6ec;
  border-radius: 10px;
  padding: 6px 16px;
  cursor: pointer;
}
.qq-number:hover { border-color: var(--brand); }

/* ---------- footer ---------- */
.site-footer { border-top: 1px solid var(--line); background: #fff; padding: 30px 0 22px; }
.footer-inner { display: flex; justify-content: space-between; gap: 20px; flex-wrap: wrap; }
.footer-links { display: flex; gap: 18px; align-items: center; }
.footer-links a { color: var(--muted); font-size: 14px; }
.footer-links a:hover { color: var(--brand); }
.footer-legal {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--line);
  color: var(--muted);
  font-size: 13px;
}

/* ---------- responsive ---------- */
@media (max-width: 980px) {
  .hero-grid { grid-template-columns: 1fr; gap: 36px; }
  .cards { grid-template-columns: repeat(2, 1fr); }
  .steps { grid-template-columns: 1fr; }
  .shots { grid-template-columns: 1fr; }
  .download-card { grid-template-columns: 1fr; }
  .requirements { grid-template-columns: repeat(2, 1fr); }
  .nav { display: none; }
}
@media (max-width: 620px) {
  .cards { grid-template-columns: 1fr; }
  .header-actions .btn-ghost { display: none; }
  .banner, .contact-card { flex-direction: column; align-items: flex-start; }
  .contact-action { align-items: flex-start; }
  .hero { padding: 48px 0 56px; }
  .section { padding: 52px 0; }
  .requirements { grid-template-columns: 1fr; }
  .footer-inner { flex-direction: column; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .btn, .card { transition: none; }
}