:root {
  --primary: #6366f1;
  --primary-dark: #4f46e5;
  --accent: #22d3ee;
  --text: #0f172a;
  --text-muted: #64748b;
  --bg: #ffffff;
  --bg-soft: #f8fafc;
  --border: #e2e8f0;
  --radius: 10px;
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", "PingFang SC", "Microsoft YaHei", sans-serif;
}
* { box-sizing: border-box; margin: 0; padding: 0; }
body { font-family: var(--font); color: var(--text); background: var(--bg); line-height: 1.65; -webkit-font-smoothing: antialiased; }
a { color: var(--primary); text-decoration: none; }
a:hover { text-decoration: underline; }

/* Nav */
.nav { position: sticky; top: 0; z-index: 100; background: rgba(255,255,255,0.92); backdrop-filter: blur(10px); border-bottom: 1px solid var(--border); }
.nav-inner { max-width: 1100px; margin: 0 auto; display: flex; align-items: center; gap: 32px; padding: 14px 24px; }
.nav-logo { font-weight: 700; font-size: 20px; color: var(--text); display: flex; align-items: center; gap: 8px; }
.nav-logo:hover { text-decoration: none; color: var(--text); }
.nav-logo .dot { width: 12px; height: 12px; border-radius: 50%; background: linear-gradient(135deg, var(--primary), var(--accent)); }
.nav-links { display: flex; gap: 24px; flex: 1; }
.nav-links a { color: var(--text-muted); font-size: 14px; font-weight: 500; }
.nav-links a:hover { color: var(--text); text-decoration: none; }
.nav-links a.active { color: var(--primary); }
.lang-switch { display: flex; gap: 2px; border: 1px solid var(--border); border-radius: 6px; padding: 2px; }
.lang-switch button { background: transparent; border: none; padding: 4px 10px; font-size: 12px; cursor: pointer; border-radius: 4px; color: var(--text-muted); font-family: inherit; }
.lang-switch button.active { background: var(--primary); color: white; }

/* Hero */
.hero { max-width: 900px; margin: 0 auto; padding: 80px 24px 60px; text-align: center; }
.hero h1 { font-size: 52px; line-height: 1.15; font-weight: 800; letter-spacing: -0.02em; margin-bottom: 20px; }
.hero h1 .grad { background: linear-gradient(135deg, var(--primary), var(--accent)); -webkit-background-clip: text; background-clip: text; -webkit-text-fill-color: transparent; }
.hero p { font-size: 18px; color: var(--text-muted); margin-bottom: 32px; max-width: 620px; margin-left: auto; margin-right: auto; }
.btn-row { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.btn { display: inline-block; padding: 12px 24px; border-radius: var(--radius); font-size: 15px; font-weight: 600; cursor: pointer; border: none; font-family: inherit; transition: all 0.2s; }
.btn-primary { background: var(--primary); color: white; }
.btn-primary:hover { background: var(--primary-dark); text-decoration: none; color: white; }
.btn-secondary { background: white; color: var(--text); border: 1px solid var(--border); }
.btn-secondary:hover { background: var(--bg-soft); text-decoration: none; color: var(--text); }

/* Sections */
.section { max-width: 1100px; margin: 0 auto; padding: 60px 24px; }
.section-title { font-size: 32px; font-weight: 700; text-align: center; margin-bottom: 12px; letter-spacing: -0.01em; }
.section-sub { text-align: center; color: var(--text-muted); margin-bottom: 48px; font-size: 16px; }

/* Grid */
.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; }
.card { border: 1px solid var(--border); border-radius: var(--radius); padding: 24px; background: white; transition: all 0.2s; }
.card:hover { border-color: var(--primary); transform: translateY(-2px); box-shadow: 0 8px 24px rgba(99,102,241,0.1); }
.card-icon { width: 40px; height: 40px; border-radius: 8px; background: linear-gradient(135deg, var(--primary), var(--accent)); display: flex; align-items: center; justify-content: center; color: white; font-size: 20px; margin-bottom: 16px; }
.card h3 { font-size: 17px; margin-bottom: 8px; }
.card p { font-size: 14px; color: var(--text-muted); }

/* Steps */
.steps { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 16px; }
.step { text-align: center; padding: 20px 12px; }
.step-num { width: 40px; height: 40px; border-radius: 50%; background: var(--primary); color: white; display: flex; align-items: center; justify-content: center; margin: 0 auto 12px; font-weight: 700; }
.step h4 { font-size: 15px; margin-bottom: 6px; }
.step p { font-size: 13px; color: var(--text-muted); }

/* Pricing */
.pricing { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 20px; max-width: 900px; margin: 0 auto; }
.price-card { border: 1px solid var(--border); border-radius: var(--radius); padding: 28px; background: white; }
.price-card.featured { border-color: var(--primary); border-width: 2px; position: relative; }
.price-card.featured::before { content: 'Popular'; position: absolute; top: -12px; left: 50%; transform: translateX(-50%); background: var(--primary); color: white; font-size: 11px; padding: 4px 10px; border-radius: 12px; font-weight: 600; letter-spacing: 0.5px; }
.price-card h3 { font-size: 18px; margin-bottom: 8px; }
.price-amount { font-size: 32px; font-weight: 800; margin: 16px 0; }
.price-amount small { font-size: 14px; font-weight: 400; color: var(--text-muted); }
.price-card ul { list-style: none; margin: 20px 0; }
.price-card li { padding: 6px 0; font-size: 14px; color: var(--text-muted); }
.price-card li::before { content: '✓'; color: var(--primary); margin-right: 8px; font-weight: 700; }

/* Footer */
.footer { border-top: 1px solid var(--border); margin-top: 80px; padding: 40px 24px; background: var(--bg-soft); }
.footer-inner { max-width: 1100px; margin: 0 auto; display: flex; flex-wrap: wrap; gap: 40px; }
.footer-col { min-width: 140px; }
.footer-col h4 { font-size: 14px; margin-bottom: 12px; }
.footer-col a { display: block; font-size: 13px; color: var(--text-muted); padding: 4px 0; }
.footer-col a:hover { color: var(--text); text-decoration: none; }
.footer-bottom { max-width: 1100px; margin: 32px auto 0; padding-top: 24px; border-top: 1px solid var(--border); color: var(--text-muted); font-size: 13px; }

/* Content pages */
.content-page { max-width: 780px; margin: 0 auto; padding: 60px 24px; }
.content-page h1 { font-size: 40px; margin-bottom: 16px; letter-spacing: -0.01em; }
.content-page h2 { font-size: 24px; margin: 40px 0 12px; }
.content-page h3 { font-size: 18px; margin: 24px 0 8px; }
.content-page p { color: var(--text-muted); margin-bottom: 12px; }
.content-page ul { margin: 12px 0 20px 20px; color: var(--text-muted); }
.content-page li { margin-bottom: 6px; }
.content-page code { background: var(--bg-soft); border: 1px solid var(--border); padding: 2px 6px; border-radius: 4px; font-size: 0.9em; font-family: 'SF Mono', Menlo, Consolas, monospace; }

@media (max-width: 640px) {
  .hero h1 { font-size: 36px; }
  .hero p { font-size: 16px; }
  .nav-links { display: none; }
  .section-title { font-size: 26px; }
  .content-page h1 { font-size: 32px; }
}