:root {
  --bg: #f6f8fc;
  --surface: #ffffff;
  --ink: #0f1b2d;
  --muted: #5b6b82;
  --line: #e4e9f2;
  --accent: #2f6bff;
  --accent-2: #6a5cff;
  --accent-soft: #eaf0ff;
  --green: #6b9e4a;
  --green-dark: #4f7a34;
  --amber: #e08a3c;
  --radius: 16px;
  --shadow-sm: 0 1px 2px rgba(15, 27, 45, .05), 0 4px 12px rgba(15, 27, 45, .05);
  --shadow-md: 0 8px 30px rgba(15, 27, 45, .08);
  --shadow-lg: 0 20px 60px rgba(47, 107, 255, .14);
  --font: "PingFang SC", "Microsoft YaHei", "Noto Sans CJK SC", system-ui, -apple-system, sans-serif;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  font-family: var(--font);
  color: var(--ink);
  background: var(--bg);
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; }
code {
  background: #eef2f8;
  padding: 2px 7px;
  border-radius: 6px;
  font-size: .9em;
}

/* ============ 导航 ============ */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, .82);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--line);
}
.nav-inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 14px 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.brand { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 19px; }
.nav-left { display: flex; align-items: center; gap: 12px; min-width: 0; }
.brand-mark {
  display: grid; place-items: center;
  width: 34px; height: 34px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff; font-size: 18px;
  box-shadow: 0 6px 16px rgba(47, 107, 255, .35);
}
.brand-text { letter-spacing: .5px; }
.nav-links { display: flex; align-items: center; gap: 4px; flex-wrap: wrap; }
.nav-link {
  padding: 8px 14px;
  border-radius: 999px;
  color: var(--muted);
  font-size: 15px;
  font-weight: 500;
  transition: all .16s ease;
}
.nav-link:hover { color: var(--ink); background: var(--accent-soft); }
.nav-link.is-active { color: var(--accent); font-weight: 600; }
.nav-cta {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff !important;
  box-shadow: 0 6px 16px rgba(47, 107, 255, .28);
}
.nav-cta:hover { filter: brightness(1.05); }
.nav-toggle {
  display: none;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 10px;
  padding: 6px 12px;
  font-size: 18px;
  cursor: pointer;
}

/* ============ Hero ============ */
.hero {
  position: relative;
  overflow: hidden;
  padding: 88px 22px 76px;
  text-align: center;
}
.hero-bg {
  position: absolute;
  inset: 0;
  z-index: -1;
  background:
    radial-gradient(900px 420px at 20% -10%, rgba(47, 107, 255, .16), transparent 60%),
    radial-gradient(760px 380px at 85% 0%, rgba(106, 92, 255, .14), transparent 55%),
    radial-gradient(600px 300px at 50% 120%, rgba(107, 158, 74, .10), transparent 60%);
}
.hero-inner { max-width: 820px; margin: 0 auto; }
.hero-eyebrow {
  display: inline-block;
  font-size: 13px;
  letter-spacing: 2px;
  color: var(--accent);
  background: var(--accent-soft);
  padding: 6px 14px;
  border-radius: 999px;
  font-weight: 600;
}
.hero-title {
  font-size: clamp(34px, 6vw, 58px);
  margin: 20px 0 14px;
  letter-spacing: -.5px;
  line-height: 1.15;
}
.grad {
  background: linear-gradient(100deg, var(--accent), var(--accent-2) 60%, #9a5cff);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-sub { color: var(--muted); font-size: 18px; max-width: 620px; margin: 0 auto 30px; }
.hero-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; }

.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 13px 26px;
  border-radius: 999px;
  font-size: 16px;
  font-weight: 600;
  transition: all .18s ease;
  cursor: pointer;
  border: 1px solid transparent;
}
.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #fff;
  box-shadow: 0 10px 26px rgba(47, 107, 255, .35);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 14px 32px rgba(47, 107, 255, .45); }
.btn-ghost { background: #fff; color: var(--ink); border-color: var(--line); box-shadow: var(--shadow-sm); }
.btn-ghost:hover { border-color: var(--accent); color: var(--accent); }
.btn-sm { padding: 9px 18px; font-size: 14px; }

.hero-stats { display: flex; gap: 40px; justify-content: center; margin-top: 46px; flex-wrap: wrap; }
.hstat { display: flex; flex-direction: column; }
.hstat b { font-size: 30px; font-weight: 800; background: linear-gradient(120deg, var(--accent), var(--accent-2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hstat span { color: var(--muted); font-size: 13px; }

/* ============ Section ============ */
.section { max-width: 1120px; margin: 0 auto; padding: 72px 22px; }
.section-alt { background: linear-gradient(180deg, #fff, var(--bg)); }
.section-head { text-align: center; margin-bottom: 40px; }
.section-eyebrow { font-size: 12px; letter-spacing: 3px; color: var(--accent); font-weight: 700; text-transform: uppercase; }
.section-title { font-size: clamp(26px, 4vw, 38px); margin: 8px 0 10px; }
.section-desc { color: var(--muted); max-width: 560px; margin: 0 auto; font-size: 16px; }

/* ============ 卡片 ============ */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 22px; }
.card {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px;
  box-shadow: var(--shadow-sm);
  transition: transform .2s ease, box-shadow .2s ease;
  display: flex;
  flex-direction: column;
}
.card:hover { transform: translateY(-4px); box-shadow: var(--shadow-md); }
.card-featured { border-color: rgba(107, 158, 74, .4); background: linear-gradient(180deg, #fbfff6, #fff); }
.card-badge {
  position: absolute; top: 18px; right: 18px;
  font-size: 12px; font-weight: 700;
  background: #e8f7ec; color: #1f7a3d;
  padding: 4px 10px; border-radius: 999px;
}
.badge-soon { background: #f1f3f7; color: var(--muted); }
.card-icon { font-size: 38px; margin-bottom: 12px; }
.card-title { font-size: 20px; margin: 0 0 8px; }
.card-desc { color: var(--muted); font-size: 15px; margin: 0 0 16px; }
.card-tags { display: flex; gap: 8px; flex-wrap: wrap; margin: 0 0 18px; padding: 0; list-style: none; }
.card-tags li {
  font-size: 12px; color: var(--muted);
  background: #f1f4f9; padding: 4px 10px; border-radius: 999px;
}
.card-actions { margin-top: auto; display: flex; gap: 10px; flex-wrap: wrap; }

/* ============ Demo ============ */
.demo-frame {
  max-width: 980px;
  margin: 0 auto;
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid var(--line);
  background: #fff;
  box-shadow: var(--shadow-lg);
}
.demo-bar {
  display: flex; align-items: center; gap: 7px;
  padding: 12px 16px;
  background: #f2f5fa;
  border-bottom: 1px solid var(--line);
}
.dot { width: 12px; height: 12px; border-radius: 50%; }
.dot-r { background: #ff5f57; }
.dot-y { background: #febc2e; }
.dot-g { background: #28c840; }
.demo-url { margin-left: 8px; font-size: 13px; color: var(--muted); font-family: ui-monospace, SFMono-Regular, Menlo, monospace; }
.demo-open { margin-left: auto; color: var(--muted); font-weight: 700; padding: 2px 8px; }
.demo-open:hover { color: var(--accent); }
.demo-iframe { width: 100%; height: 680px; border: 0; display: block; background: #fff; }

/* ============ About ============ */
.about-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 22px; }
.about-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 26px;
  box-shadow: var(--shadow-sm);
}
.about-card h3 { margin: 0 0 10px; font-size: 18px; }
.about-card p { color: var(--muted); margin: 0; font-size: 15px; }
.placeholder-note { display: block; margin-top: 10px; font-style: normal; color: var(--amber); font-size: 13px; }

/* ============ Contact ============ */
.contact-card {
  max-width: 680px;
  margin: 0 auto;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-sm);
  overflow: hidden;
}
.contact-item {
  display: flex; align-items: center; gap: 16px;
  padding: 20px 26px;
  border-bottom: 1px solid var(--line);
}
.contact-item:last-child { border-bottom: 0; }
a.contact-item:hover { background: var(--accent-soft); }
.contact-icon { font-size: 26px; }
.contact-meta { display: flex; flex-direction: column; }
.contact-meta b { font-size: 15px; }
.contact-meta em { font-style: normal; color: var(--muted); font-size: 14px; }

/* ============ Footer ============ */
.site-footer { border-top: 1px solid var(--line); background: #fff; }
.footer-inner {
  max-width: 1120px; margin: 0 auto; padding: 26px 22px;
  display: flex; align-items: center; justify-content: space-between; gap: 12px; flex-wrap: wrap;
  font-size: 14px; color: var(--muted);
}
.footer-inner b { color: var(--ink); }
.footer-meta { font-size: 13px; }

/* ============ 响应式 ============ */
@media (max-width: 760px) {
  .nav-toggle { display: block; }
  .nav-links {
    display: none;
    position: absolute; top: 100%; left: 0; right: 0;
    background: #fff; border-bottom: 1px solid var(--line);
    flex-direction: column; align-items: stretch; padding: 10px 16px 16px; gap: 2px;
  }
  .nav-links.open { display: flex; }
  .demo-iframe { height: 560px; }
  .hero { padding: 60px 18px 56px; }
  .hero-stats { gap: 24px; }
}