:root {
  --bg: #f7f8fb;
  --card: #ffffff;
  --text: #1a1a2e;
  --text-dim: #6b7280;
  --primary: #5b5bd6;
  --primary-hover: #4a4ac0;
  --border: #e5e7eb;
  --radius: 16px;
  --font: -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  font-size: 16px;
  line-height: 1.7;
}
a { text-decoration: none; color: inherit; }

/* 顶部导航 */
.site-header {
  position: sticky; top: 0; z-index: 10;
  background: rgba(255,255,255,0.9); backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1120px; margin: 0 auto; padding: 14px 24px;
  display: flex; align-items: center; gap: 32px;
}
.brand { font-size: 20px; font-weight: 800; letter-spacing: 1px; }
.brand .dot { color: var(--primary); }
.nav-links { display: flex; gap: 24px; color: var(--text-dim); flex: 1; }
.nav-links a:hover { color: var(--text); }
.nav-actions { display: flex; gap: 12px; }

.btn-outline, .btn-solid {
  display: inline-block; padding: 9px 18px; border-radius: 9px;
  font-size: 14px; font-weight: 600; cursor: pointer; transition: all .15s;
}
.btn-outline { border: 1px solid var(--border); color: var(--text); }
.btn-outline:hover { border-color: var(--primary); color: var(--primary); }
.btn-solid { background: var(--primary); color: #fff; }
.btn-solid:hover { background: var(--primary-hover); }
.btn-lg { padding: 14px 30px; font-size: 16px; }

/* 首屏 */
.hero { text-align: center; padding: 90px 24px 70px; }
.hero h1 { font-size: 42px; font-weight: 800; letter-spacing: -1px; margin-bottom: 16px; }
.hero-sub { color: var(--text-dim); font-size: 18px; margin-bottom: 36px; }
.hero-actions { display: flex; gap: 16px; justify-content: center; }

/* 功能 */
.features, .pricing { max-width: 1120px; margin: 0 auto; padding: 60px 24px; }
.features h2, .pricing h2 { font-size: 30px; font-weight: 800; text-align: center; margin-bottom: 36px; }
.section-sub { text-align: center; color: var(--text-dim); margin-top: -24px; margin-bottom: 36px; }
.feature-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(240px, 1fr)); gap: 20px; }
.feature-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 28px 24px; transition: transform .15s, box-shadow .15s;
}
.feature-card:hover { transform: translateY(-4px); box-shadow: 0 12px 28px rgba(0,0,0,0.06); }
.feature-icon { font-size: 32px; margin-bottom: 14px; }
.feature-card h3 { font-size: 18px; margin-bottom: 10px; }
.feature-card p { color: var(--text-dim); font-size: 14px; }

/* 定价 */
.pricing-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: 20px; }
.pricing-card {
  background: var(--card); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 30px 26px; text-align: center;
}
.pricing-card.highlight { border-color: var(--primary); box-shadow: 0 8px 24px rgba(91,91,214,0.12); }
.pricing-card h3 { font-size: 18px; margin-bottom: 12px; }
.price { font-size: 26px; font-weight: 800; color: var(--primary); margin-bottom: 10px; }
.pricing-card p { color: var(--text-dim); font-size: 14px; }

/* 页脚 */
.site-footer { text-align: center; padding: 40px 24px; color: var(--text-dim); font-size: 13px; border-top: 1px solid var(--border); background: #fff; }
.copyright { margin-top: 8px; }