:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #12121a;
  --bg-card: #1a1a26;
  --bg-card-hover: #222233;
  --text-primary: #e8e8f0;
  --text-secondary: #9090a8;
  --text-muted: #606078;
  --accent: #7c6aff;
  --accent-glow: rgba(124, 106, 255, 0.15);
  --accent-secondary: #4ad9d9;
  --border: #2a2a3a;
  --gradient-1: linear-gradient(135deg, #7c6aff, #4ad9d9);
  --gradient-2: linear-gradient(135deg, #ff6b8a, #7c6aff);
  --radius: 12px;
  --radius-lg: 20px;
  --max-width: 1100px;
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { opacity: 0.85; }

/* Nav */
nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border);
}
nav .inner {
  max-width: var(--max-width); margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 24px; height: 60px;
}
nav .logo {
  font-size: 18px; font-weight: 700;
  background: var(--gradient-1); -webkit-background-clip: text;
  -webkit-text-fill-color: transparent; background-clip: text;
}
nav .links { display: flex; gap: 28px; }
nav .links a {
  color: var(--text-secondary); font-size: 14px; transition: color 0.2s;
}
nav .links a:hover { color: var(--text-primary); }

/* Hero */
.hero {
  min-height: 100vh; display: flex; align-items: center; justify-content: center;
  text-align: center; padding: 120px 24px 80px;
  position: relative; overflow: hidden;
}
.hero::before {
  content: ''; position: absolute; top: 50%; left: 50%;
  width: 800px; height: 800px;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
  transform: translate(-50%, -50%); pointer-events: none;
}
.hero-content { position: relative; max-width: 720px; }
.hero-badge {
  display: inline-block; padding: 6px 16px; border-radius: 100px;
  background: rgba(124, 106, 255, 0.1); border: 1px solid rgba(124, 106, 255, 0.2);
  color: var(--accent); font-size: 13px; font-weight: 500; margin-bottom: 24px;
}
.hero h1 {
  font-size: clamp(36px, 6vw, 60px); font-weight: 800; line-height: 1.15;
  margin-bottom: 20px; letter-spacing: -0.02em;
}
.hero h1 .highlight { background: var(--gradient-1); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero p {
  font-size: 18px; color: var(--text-secondary); max-width: 560px; margin: 0 auto 36px;
}
.hero-actions { display: flex; gap: 12px; justify-content: center; flex-wrap: wrap; }
.btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 12px 28px; border-radius: 100px; font-size: 15px; font-weight: 600;
  transition: all 0.2s; cursor: pointer; border: none;
}
.btn-primary {
  background: var(--gradient-1); color: #fff;
  box-shadow: 0 4px 20px rgba(124, 106, 255, 0.3);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 8px 30px rgba(124, 106, 255, 0.4); }
.btn-outline {
  background: transparent; color: var(--text-primary);
  border: 1px solid var(--border);
}
.btn-outline:hover { border-color: var(--accent); background: rgba(124, 106, 255, 0.05); }

/* Sections */
section { padding: 100px 24px; }
.section-inner { max-width: var(--max-width); margin: 0 auto; }
.section-label {
  display: inline-block; font-size: 12px; font-weight: 600; letter-spacing: 0.1em;
  text-transform: uppercase; color: var(--accent); margin-bottom: 12px;
}
.section-title {
  font-size: clamp(28px, 4vw, 40px); font-weight: 700; margin-bottom: 16px;
  letter-spacing: -0.02em;
}
.section-desc {
  font-size: 16px; color: var(--text-secondary); max-width: 600px; margin-bottom: 48px;
}

/* Features Grid */
.features-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 20px;
}
.feature-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 32px;
  transition: all 0.3s; position: relative; overflow: hidden;
}
.feature-card:hover {
  background: var(--bg-card-hover); border-color: rgba(124, 106, 255, 0.2);
  transform: translateY(-4px);
}
.feature-card .icon {
  width: 44px; height: 44px; border-radius: 10px;
  display: flex; align-items: center; justify-content: center;
  font-size: 20px; margin-bottom: 16px;
}
.feature-card h3 { font-size: 17px; font-weight: 600; margin-bottom: 8px; }
.feature-card p { font-size: 14px; color: var(--text-secondary); line-height: 1.6; }

/* Capabilities */
.capabilities-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 16px;
}
.cap-item {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 20px 24px;
  display: flex; align-items: center; gap: 14px;
  transition: all 0.2s; position: relative;
}
.cap-item:hover { border-color: rgba(124, 106, 255, 0.2); }
.cap-item .dot {
  width: 8px; height: 8px; border-radius: 50%; flex-shrink: 0;
}
.cap-item span { font-size: 14px; }

.cap-item::after {
  content: attr(title);
  position: absolute; bottom: calc(100% + 8px); left: 50%;
  transform: translateX(-50%) scale(0.9);
  background: #2a2a3a; color: #e8e8f0;
  padding: 6px 12px; border-radius: 6px;
  font-size: 12px; white-space: nowrap;
  opacity: 0; pointer-events: none;
  transition: all 0.2s;
}
.cap-item:hover::after {
  opacity: 1; transform: translateX(-50%) scale(1);
}

/* Scenarios */
.scenarios-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 20px;
}
.scenario-card {
  background: var(--bg-card); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 36px 32px;
  text-align: center; transition: all 0.3s;
}
.scenario-card:hover {
  background: var(--bg-card-hover); transform: translateY(-4px);
}
.scenario-card .emoji { font-size: 40px; margin-bottom: 16px; }
.scenario-card h3 { font-size: 17px; font-weight: 600; margin-bottom: 8px; }
.scenario-card p { font-size: 14px; color: var(--text-secondary); }

/* FAQ */
.faq-list { max-width: 720px; margin: 0 auto; }
.faq-item {
  border-bottom: 1px solid var(--border); padding: 20px 0;
}
.faq-question {
  display: flex; justify-content: space-between; align-items: center;
  cursor: pointer; font-size: 16px; font-weight: 500;
  user-select: none; transition: color 0.2s;
}
.faq-question:hover { color: var(--accent); }
.faq-question .arrow {
  font-size: 12px; transition: transform 0.3s; color: var(--text-muted);
}
.faq-item.open .faq-question .arrow { transform: rotate(180deg); }
.faq-answer {
  max-height: 0; overflow: hidden; transition: max-height 0.3s ease, padding 0.3s ease;
  color: var(--text-secondary); font-size: 14px; line-height: 1.7;
}
.faq-item.open .faq-answer { max-height: 300px; padding-top: 12px; }

/* Footer */
footer {
  border-top: 1px solid var(--border); padding: 48px 24px;
  text-align: center; color: var(--text-muted); font-size: 13px;
}
footer .beian { margin-top: 8px; }
footer .beian a { color: var(--text-muted); text-decoration: none; }
footer .beian a:hover { color: var(--text-secondary); }

/* Animations */
.fade-in {
  opacity: 0; transform: translateY(24px); transition: all 0.6s ease;
}
.fade-in.visible { opacity: 1; transform: translateY(0); }

/* Responsive */
@media (max-width: 768px) {
  nav .links { display: none; }
  .features-grid, .scenarios-grid { grid-template-columns: 1fr; }
  .capabilities-grid { grid-template-columns: 1fr 1fr; }
  section { padding: 60px 20px; }
  .hero { min-height: 80vh; padding: 100px 20px 60px; }
}
@media (max-width: 480px) {
  .capabilities-grid { grid-template-columns: 1fr; }
}