:root {
  --fg: #17203a;
  --dim: #5b6579;
  --accent: #4d6bff;
  --accent2: #7c4dff;
  --border: #e6e9f2;
  --bg: #ffffff;
  --alt: #f6f8fd;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font: 15px/1.75 -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--fg);
  background: var(--bg);
}
.container { max-width: 1120px; margin: 0 auto; padding: 0 22px; }
.center { text-align: center; }

/* ------------------------------------------------------------------- nav */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,.85);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav-in { display: flex; align-items: center; gap: 26px; height: 62px; }
.brand { font-size: 20px; font-weight: 800; color: var(--fg); letter-spacing: .5px; }
.brand b { background: linear-gradient(135deg, var(--accent), var(--accent2)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.nav nav { display: flex; gap: 20px; flex: 1; }
.nav nav a { color: var(--dim); font-size: 14px; }
.nav nav a:hover { color: var(--fg); }
.nav-cta { display: flex; gap: 10px; }

.btn {
  display: inline-block;
  padding: 8px 18px;
  border-radius: 9px;
  border: 1px solid var(--border);
  color: var(--fg);
  background: #fff;
  font-size: 14px;
  cursor: pointer;
  text-decoration: none;
}
.btn:hover { border-color: var(--accent); }
.btn.primary { background: linear-gradient(135deg, var(--accent), var(--accent2)); color: #fff; border: 0; }
.btn.ghost { background: transparent; }
.btn.big { padding: 12px 26px; font-size: 15.5px; border-radius: 11px; }

/* ------------------------------------------------------------------ hero */
.hero {
  background:
    radial-gradient(800px 400px at 85% -10%, rgba(124,77,255,.12), transparent 60%),
    radial-gradient(900px 500px at 5% 10%, rgba(77,107,255,.12), transparent 60%),
    var(--alt);
  padding: 72px 0 80px;
  overflow: hidden;
}
.hero-in { display: grid; grid-template-columns: 1fr 1.1fr; gap: 48px; align-items: center; }
.badge {
  display: inline-block;
  font-size: 12.5px;
  color: var(--accent);
  background: rgba(77,107,255,.1);
  border: 1px solid rgba(77,107,255,.25);
  padding: 4px 12px;
  border-radius: 20px;
  margin-bottom: 18px;
  letter-spacing: 1px;
}
.hero h1 { font-size: 42px; line-height: 1.25; margin: 0 0 16px; letter-spacing: 1px; }
.lead { color: var(--dim); font-size: 16.5px; margin: 0 0 26px; }
.hero-btns { display: flex; gap: 12px; flex-wrap: wrap; }
.hero-points { display: flex; gap: 18px; list-style: none; padding: 0; margin: 26px 0 0; color: var(--dim); font-size: 13.5px; flex-wrap: wrap; }
.hero-shot img {
  width: 100%;
  border-radius: 14px;
  border: 1px solid var(--border);
  box-shadow: 0 30px 80px rgba(23,32,58,.25);
}

/* --------------------------------------------------------------- sections */
.section { padding: 76px 0; }
.section.alt { background: var(--alt); }
.sec-title { font-size: 30px; text-align: center; margin: 0 0 10px; letter-spacing: 1px; }
.sec-sub { text-align: center; color: var(--dim); margin: 0 0 44px; }

.grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.feat {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 26px 24px;
  transition: transform .15s ease, box-shadow .15s ease;
}
.feat:hover { transform: translateY(-4px); box-shadow: 0 16px 40px rgba(23,32,58,.1); }
.feat .ico { font-size: 28px; margin-bottom: 10px; }
.feat h3 { margin: 0 0 8px; font-size: 17px; }
.feat p { margin: 0; color: var(--dim); font-size: 14px; }

.shot {
  max-width: 100%;
  border-radius: 14px;
  border: 1px solid var(--border);
  box-shadow: 0 24px 70px rgba(23,32,58,.2);
  margin-top: 10px;
}

/* ---------------------------------------------------------------- pricing */
.plans { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 20px; }
.plan {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 30px 26px;
  text-align: center;
}
.plan h3 { margin: 0 0 12px; font-size: 18px; }
.plan .price { font-size: 40px; font-weight: 800; color: var(--accent); margin-bottom: 10px; }
.plan .price span { font-size: 14px; font-weight: 400; color: var(--dim); }
.plan p { color: var(--dim); font-size: 13.5px; margin: 0; }

/* ------------------------------------------------------------------ about */
.about { max-width: 760px; margin: 0 auto; color: var(--dim); }
.about-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-top: 30px; }
.about-grid > div { background: #fff; border: 1px solid var(--border); border-radius: 12px; padding: 18px 20px; }
.about-grid h4 { margin: 0 0 8px; color: var(--fg); }
.about-grid p { margin: 0; font-size: 13.5px; }

/* ------------------------------------------------------------------ footer */
.foot { border-top: 1px solid var(--border); padding: 26px 0; }
.foot-in { display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap; font-size: 13px; color: var(--dim); }

@media (max-width: 900px) {
  .hero-in { grid-template-columns: 1fr; }
  .grid { grid-template-columns: 1fr 1fr; }
  .nav nav { display: none; }
}
@media (max-width: 600px) {
  .grid, .about-grid { grid-template-columns: 1fr; }
  .hero h1 { font-size: 30px; }
}