:root {
  --blue: #3370ff;
  --blue-dark: #245bdb;
  --purple: #7b5cff;
  --grad: linear-gradient(135deg, #3370ff 0%, #7b5cff 100%);
  --bg: #ffffff;
  --bg-alt: #f7f8fa;
  --text: #1f2329;
  --text-sub: #646a73;
  --text-light: #8f959e;
  --border: #e5e6eb;
  --radius: 16px;
  --radius-lg: 24px;
  --shadow: 0 8px 24px rgba(31,35,41,0.06);
  --shadow-lg: 0 16px 48px rgba(51,112,255,0.12);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Microsoft YaHei", "Segoe UI", Roboto, sans-serif;
  color: var(--text);
  background: var(--bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { text-decoration: none; color: inherit; }

/* 顶部通告栏 */
.topbar {
  background: var(--grad);
  color: #fff;
  font-size: 14px;
}
.topbar-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 8px 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
}
.topbar-link { color: #fff; font-weight: 600; text-decoration: underline; }

/* 导航 */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  gap: 32px;
}
.logo { display: flex; align-items: center; gap: 8px; font-size: 20px; font-weight: 700; }
.logo-image { display: block; width: 136px; height: 32px; object-fit: contain; }
.nav-menu { display: flex; gap: 24px; flex: 1; }
.nav-menu a { color: var(--text-sub); font-size: 15px; transition: color .2s; }
.nav-menu a:hover { color: var(--blue); }
.nav-actions { display: flex; gap: 12px; }

/* 按钮 */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 10px 22px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  transition: all .2s;
  border: none;
}
.btn-lg { padding: 14px 32px; font-size: 16px; }
.btn-primary { background: var(--blue); color: #fff; }
.btn-primary:hover { background: var(--blue-dark); box-shadow: var(--shadow-lg); }
.btn-outline { background: #fff; color: var(--blue); border: 1.5px solid var(--blue); }
.btn-outline:hover { background: #f0f5ff; }
.btn-ghost { color: var(--text-sub); }
.btn-ghost:hover { color: var(--blue); }

/* Hero */
.hero {
  background: linear-gradient(180deg, #f0f5ff 0%, #ffffff 100%);
  padding: 80px 24px 64px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  top: -120px; left: 50%; transform: translateX(-50%);
  width: 600px; height: 300px;
  background: radial-gradient(ellipse, rgba(123,92,255,0.15) 0%, transparent 70%);
  pointer-events: none;
}
.hero-inner { max-width: 900px; margin: 0 auto; position: relative; }
.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--blue);
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 24px;
}
.hero-title {
  font-size: 48px;
  font-weight: 800;
  line-height: 1.25;
  letter-spacing: -0.5px;
  margin-bottom: 20px;
}
.grad {
  background: var(--grad);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero-sub { font-size: 18px; color: var(--text-sub); margin-bottom: 32px; }
.hero-cta { display: flex; gap: 16px; justify-content: center; margin-bottom: 48px; }
.hero-stats {
  display: flex; justify-content: center; gap: 48px;
  flex-wrap: wrap;
}
.stat { text-align: center; }
.stat-num {
  display: block;
  font-size: 32px; font-weight: 800;
  background: var(--grad);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.stat-label { font-size: 14px; color: var(--text-light); }

/* 通用 section */
.section { padding: 80px 24px; }
.section-alt { background: var(--bg-alt); }
.section-inner { max-width: 1200px; margin: 0 auto; }
.section-title {
  font-size: 36px; font-weight: 800;
  text-align: center;
  margin-bottom: 16px;
  letter-spacing: -0.5px;
}
.section-sub {
  text-align: center;
  color: var(--text-sub);
  font-size: 17px;
  margin-bottom: 48px;
}

/* 痛点 */
.pain-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 16px;
}
.pain-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  font-size: 15px;
  color: var(--text-sub);
  transition: all .2s;
}
.pain-card:hover { border-color: var(--blue); box-shadow: var(--shadow); transform: translateY(-2px); }

/* 产品 */
.product-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: 24px;
}
.product-card {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: all .2s;
}
.product-card:hover { box-shadow: var(--shadow-lg); transform: translateY(-4px); border-color: transparent; }
.product-icon { font-size: 36px; margin-bottom: 16px; }
.product-card h3 { font-size: 20px; margin-bottom: 12px; }
.product-card p { color: var(--text-sub); font-size: 15px; }

/* AI */
.ai-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
}
.ai-item {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px 20px;
  font-size: 15px;
  position: relative;
  padding-left: 44px;
}
.ai-item::before {
  content: '✨';
  position: absolute; left: 16px; top: 18px;
}
.note { text-align: center; color: var(--text-light); font-size: 14px; margin-top: 24px; }

/* 优势 */
.adv-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 20px;
}
.adv-card {
  background: #fff;
  border-radius: var(--radius);
  padding: 24px;
  border: 1px solid var(--border);
}
.adv-card h3 { font-size: 18px; margin-bottom: 8px; color: var(--blue); }
.adv-card p { color: var(--text-sub); font-size: 14px; }

/* 流程 */
.flow-steps {
  display: flex; flex-wrap: wrap; justify-content: center;
  gap: 12px; margin-bottom: 48px;
}
.flow-step {
  display: flex; align-items: center; gap: 8px;
  background: #fff;
  border: 1px solid var(--border);
  border-radius: 999px;
  padding: 10px 18px;
  font-size: 15px;
  font-weight: 600;
}
.flow-num {
  width: 24px; height: 24px;
  display: inline-flex; align-items: center; justify-content: center;
  background: var(--grad);
  color: #fff;
  border-radius: 50%;
  font-size: 13px;
}
.flow-subtitle { text-align: center; font-size: 22px; margin-bottom: 24px; }
.deliver-grid {
  display: flex; flex-wrap: wrap; justify-content: center; gap: 12px;
}
.deliver-grid span {
  background: #f0f5ff;
  color: var(--blue);
  border-radius: 999px;
  padding: 8px 16px;
  font-size: 14px;
}

/* 案例 */
.case-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 24px;
}
.case-card {
  background: #fff;
  border-radius: var(--radius-lg);
  padding: 28px;
  border: 1px solid var(--border);
  display: flex; flex-direction: column; gap: 16px;
}
.case-quote { font-size: 15px; color: var(--text); line-height: 1.7; }
.case-author { color: var(--text-light); font-size: 14px; font-weight: 600; }

/* FAQ */
.faq-list { max-width: 800px; margin: 0 auto; }
.faq-item {
  background: #fff;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: 12px;
  overflow: hidden;
}
.faq-item summary {
  padding: 18px 24px;
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  position: relative;
}
.faq-item summary::after {
  content: '+';
  position: absolute; right: 24px; top: 50%; transform: translateY(-50%);
  font-size: 20px; color: var(--blue);
}
.faq-item[open] summary::after { content: '−'; }
.faq-item p { padding: 0 24px 18px; color: var(--text-sub); }

/* 理念 */
.philosophy-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 16px;
}
.philosophy-item {
  background: #fff;
  border-radius: var(--radius);
  padding: 20px;
  font-size: 15px;
  font-weight: 600;
  border-left: 4px solid var(--grad);
  border: 1px solid var(--border);
  border-left: 4px solid var(--blue);
}

/* CTA */
.cta {
  background: var(--grad);
  color: #fff;
  text-align: center;
}
.cta .section-title { color: #fff; }
.cta .section-sub { color: rgba(255,255,255,0.9); }
.cta .btn-primary { background: #fff; color: var(--blue); }
.cta .btn-outline { background: transparent; color: #fff; border-color: #fff; }
.contact-note {
  max-width: 700px; margin: 32px auto 0;
  color: rgba(255,255,255,0.85);
  font-size: 14px;
  line-height: 1.8;
}

/* 页脚 */
.footer { background: #1f2329; color: #fff; padding: 48px 24px 24px; }
.footer-inner {
  max-width: 1200px; margin: 0 auto;
  display: grid; grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
}
.footer-brand { font-size: 20px; font-weight: 700; }
.footer-logo { display: block; width: 152px; height: 36px; object-fit: contain; }
.footer-brand p { font-size: 14px; color: #8f959e; margin-top: 12px; font-weight: 400; }
.footer-col h4 { font-size: 15px; margin-bottom: 16px; }
.footer-col a { display: block; color: #8f959e; font-size: 14px; margin-bottom: 10px; }
.footer-col a:hover { color: #fff; }
.footer-bottom {
  max-width: 1200px; margin: 32px auto 0;
  padding-top: 24px;
  border-top: 1px solid rgba(255,255,255,0.1);
  text-align: center;
  color: #8f959e;
  font-size: 13px;
}
.footer-bottom a { color: #8f959e; }

/* 响应式 */
@media (max-width: 768px) {
  .hero-title { font-size: 32px; }
  .nav-menu { display: none; }
  .section-title { font-size: 28px; }
  .footer-inner { grid-template-columns: 1fr; }
  .hero-stats { gap: 24px; }
}

/* 滚动渐入动画 */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.fade-in.visible {
  opacity: 1;
  transform: translateY(0);
}

/* 导航高亮 */
.nav-menu a.active { color: var(--blue); font-weight: 600; }