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

:root {
  --bg: #0a0a0f;
  --bg2: #0f0f1a;
  --bg3: #141428;
  --border: rgba(255,255,255,0.08);
  --border-hover: rgba(255,255,255,0.16);
  --text: #e8e8f0;
  --text-muted: #8888aa;
  --accent: #7c6af7;
  --accent2: #a78bfa;
  --accent-glow: rgba(124,106,247,0.3);
  --green: #34d399;
  --blue: #60a5fa;
  --orange: #fb923c;
  --radius: 12px;
  --radius-lg: 20px;
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

.container { max-width: 1160px; margin: 0 auto; padding: 0 24px; }

/* ── Navbar ── */
.navbar {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  background: rgba(10,10,15,0.85);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  display: flex; align-items: center; gap: 32px;
  height: 64px;
}
.logo { display: flex; align-items: center; gap: 8px; text-decoration: none; }
.logo-icon { color: var(--accent); font-size: 18px; }
.logo-text { font-size: 18px; font-weight: 700; color: var(--text); }
.logo-accent { color: var(--accent2); }
.nav-links {
  display: flex; list-style: none; gap: 28px; margin-left: 16px; flex: 1;
}
.nav-links a {
  color: var(--text-muted); text-decoration: none; font-size: 14px; font-weight: 500;
  transition: color .2s;
}
.nav-links a:hover { color: var(--text); }
.nav-actions { display: flex; gap: 10px; margin-left: auto; }

/* ── Buttons ── */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 8px;
  padding: 9px 20px; border-radius: 8px; font-size: 14px; font-weight: 600;
  text-decoration: none; cursor: pointer; border: none; transition: all .2s;
  white-space: nowrap;
}
.btn-primary {
  background: var(--accent); color: #fff;
  box-shadow: 0 0 20px var(--accent-glow);
}
.btn-primary:hover { background: var(--accent2); box-shadow: 0 0 28px var(--accent-glow); transform: translateY(-1px); }
.btn-outline {
  background: transparent; color: var(--text);
  border: 1px solid var(--border-hover);
}
.btn-outline:hover { border-color: var(--accent); color: var(--accent); }
.btn-ghost { background: transparent; color: var(--text-muted); }
.btn-ghost:hover { color: var(--text); }
.btn-lg { padding: 13px 28px; font-size: 15px; border-radius: 10px; }
.btn-block { width: 100%; }
.btn-wechat {
  background: #07c160; color: #fff; cursor: pointer;
}
.btn-wechat:hover { background: #06ad56; }

/* ── Hero ── */
.hero {
  position: relative; padding: 160px 0 100px; overflow: hidden;
  text-align: center;
}
.hero-bg {
  position: absolute; inset: 0; z-index: 0;
  background:
    radial-gradient(ellipse 80% 60% at 50% -10%, rgba(124,106,247,0.18) 0%, transparent 70%),
    radial-gradient(ellipse 50% 40% at 80% 80%, rgba(96,165,250,0.08) 0%, transparent 60%);
}
.hero-inner { position: relative; z-index: 1; }
.hero-badge {
  display: inline-block; padding: 6px 16px; border-radius: 100px;
  background: rgba(124,106,247,0.12); border: 1px solid rgba(124,106,247,0.3);
  color: var(--accent2); font-size: 13px; font-weight: 500; margin-bottom: 28px;
}
.hero-title {
  font-size: clamp(36px, 6vw, 64px); font-weight: 800; line-height: 1.15;
  letter-spacing: -1px; margin-bottom: 20px;
}
.gradient-text {
  background: linear-gradient(135deg, var(--accent2) 0%, var(--blue) 100%);
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
  background-clip: text;
}
.hero-desc {
  font-size: 18px; color: var(--text-muted); max-width: 560px; margin: 0 auto 36px;
  line-height: 1.7;
}
.hero-actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; margin-bottom: 60px; }
.hero-stats {
  display: flex; align-items: center; justify-content: center; gap: 0;
  background: rgba(255,255,255,0.03); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 24px 40px; display: inline-flex;
}
.stat-item { text-align: center; padding: 0 32px; }
.stat-num { display: block; font-size: 26px; font-weight: 800; color: var(--text); }
.stat-label { font-size: 12px; color: var(--text-muted); margin-top: 2px; }
.stat-divider { width: 1px; height: 40px; background: var(--border); }

/* ── Section common ── */
section { padding: 96px 0; }
.section-header { text-align: center; margin-bottom: 56px; }
.section-tag {
  display: inline-block; padding: 4px 14px; border-radius: 100px;
  background: rgba(124,106,247,0.1); border: 1px solid rgba(124,106,247,0.25);
  color: var(--accent2); font-size: 12px; font-weight: 600; letter-spacing: .5px;
  text-transform: uppercase; margin-bottom: 14px;
}
.section-title { font-size: clamp(28px, 4vw, 40px); font-weight: 800; margin-bottom: 12px; }
.section-desc { color: var(--text-muted); font-size: 16px; max-width: 520px; margin: 0 auto; }

/* ── Features ── */
.features { background: var(--bg2); }
.features-grid {
  display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px;
}
.feature-card {
  background: var(--bg3); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 28px;
  transition: border-color .2s, transform .2s;
}
.feature-card:hover { border-color: var(--border-hover); transform: translateY(-3px); }
.feature-card--highlight {
  border-color: rgba(124,106,247,0.3);
  background: linear-gradient(135deg, rgba(124,106,247,0.08) 0%, var(--bg3) 100%);
}
.feature-icon { font-size: 28px; margin-bottom: 14px; }
.feature-card h3 { font-size: 17px; font-weight: 700; margin-bottom: 10px; }
.feature-card p { color: var(--text-muted); font-size: 14px; line-height: 1.65; }

/* ── Models ── */
.models-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; }
.model-card {
  background: var(--bg2); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 28px; position: relative;
  transition: border-color .2s, transform .2s;
}
.model-card:hover { border-color: var(--border-hover); transform: translateY(-3px); }
.model-card--top { border-color: rgba(251,146,60,0.3); }
.model-card--mid { border-color: rgba(124,106,247,0.3); }
.model-badge {
  position: absolute; top: 20px; right: 20px;
  padding: 3px 10px; border-radius: 100px; font-size: 11px; font-weight: 700;
  background: rgba(251,146,60,0.15); color: var(--orange); border: 1px solid rgba(251,146,60,0.3);
}
.model-badge--blue { background: rgba(124,106,247,0.15); color: var(--accent2); border-color: rgba(124,106,247,0.3); }
.model-badge--green { background: rgba(52,211,153,0.15); color: var(--green); border-color: rgba(52,211,153,0.3); }
.model-header { display: flex; align-items: center; gap: 14px; margin-bottom: 14px; }
.model-icon {
  width: 44px; height: 44px; border-radius: 10px; display: flex; align-items: center;
  justify-content: center; font-size: 20px; font-weight: 900;
}
.model-icon--opus { background: rgba(251,146,60,0.15); color: var(--orange); }
.model-icon--sonnet { background: rgba(124,106,247,0.15); color: var(--accent2); }
.model-icon--haiku { background: rgba(52,211,153,0.15); color: var(--green); }
.model-card h3 { font-size: 17px; font-weight: 700; }
.model-id { font-size: 12px; color: var(--text-muted); font-family: monospace; }
.model-desc { color: var(--text-muted); font-size: 14px; line-height: 1.65; margin-bottom: 16px; }
.model-tags {
  display: flex; flex-wrap: wrap; gap: 6px; list-style: none;
}
.model-tags li {
  padding: 3px 10px; border-radius: 100px; font-size: 12px;
  background: rgba(255,255,255,0.05); border: 1px solid var(--border); color: var(--text-muted);
}

/* ── Pricing ── */
.pricing { background: var(--bg2); }
.pricing-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 20px; align-items: start; }
.pricing-card {
  background: var(--bg3); border: 1px solid var(--border);
  border-radius: var(--radius-lg); padding: 32px; position: relative;
}
.pricing-card--featured {
  border-color: var(--accent); background: linear-gradient(160deg, rgba(124,106,247,0.1) 0%, var(--bg3) 60%);
  transform: scale(1.03);
}
.pricing-popular {
  position: absolute; top: -13px; left: 50%; transform: translateX(-50%);
  background: var(--accent); color: #fff; padding: 4px 16px; border-radius: 100px;
  font-size: 12px; font-weight: 700; white-space: nowrap;
}
.pricing-card h3 { font-size: 18px; font-weight: 700; margin-bottom: 16px; }
.price { font-size: 40px; font-weight: 800; color: var(--text); }
.price-unit { font-size: 13px; color: var(--text-muted); margin-bottom: 24px; }
.pricing-features { list-style: none; margin-bottom: 28px; }
.pricing-features li {
  padding: 8px 0; font-size: 14px; color: var(--text-muted);
  border-bottom: 1px solid var(--border);
}
.pricing-features li:last-child { border-bottom: none; }

/* ── Docs ── */
.docs-tabs { display: flex; gap: 4px; margin-bottom: 0; }
.tab-btn {
  padding: 9px 20px; border-radius: 8px 8px 0 0; font-size: 13px; font-weight: 600;
  background: var(--bg2); border: 1px solid var(--border); border-bottom: none;
  color: var(--text-muted); cursor: pointer; transition: all .2s;
}
.tab-btn--active { background: #1a1a2e; color: var(--text); border-color: var(--border-hover); }
.tab-btn:hover:not(.tab-btn--active) { color: var(--text); }
.code-block {
  background: #0d0d1f; border: 1px solid var(--border-hover);
  border-radius: 0 var(--radius) var(--radius) var(--radius); overflow: hidden;
}
.code-block.hidden { display: none; }
.code-header {
  display: flex; justify-content: space-between; align-items: center;
  padding: 12px 20px; background: rgba(255,255,255,0.03);
  border-bottom: 1px solid var(--border); font-size: 13px; color: var(--text-muted);
}
.copy-btn {
  padding: 4px 12px; border-radius: 6px; font-size: 12px; font-weight: 600;
  background: rgba(124,106,247,0.15); border: 1px solid rgba(124,106,247,0.3);
  color: var(--accent2); cursor: pointer; transition: all .2s;
}
.copy-btn:hover { background: rgba(124,106,247,0.25); }
pre { padding: 24px; overflow-x: auto; }
code { font-family: 'JetBrains Mono', 'Fira Code', monospace; font-size: 13.5px; line-height: 1.7; }
.code-keyword { color: #c792ea; }
.code-string { color: #c3e88d; }
.code-comment { color: #546e7a; font-style: italic; }
.code-number { color: #f78c6c; }

/* ── FAQ ── */
.faq { background: var(--bg2); }
.faq-list { max-width: 760px; margin: 0 auto; }
.faq-item { border-bottom: 1px solid var(--border); }
.faq-question {
  width: 100%; display: flex; justify-content: space-between; align-items: center;
  padding: 20px 0; background: none; border: none; color: var(--text);
  font-size: 15px; font-weight: 600; cursor: pointer; text-align: left; gap: 16px;
}
.faq-arrow { color: var(--text-muted); font-size: 12px; transition: transform .2s; flex-shrink: 0; }
.faq-item.open .faq-arrow { transform: rotate(180deg); }
.faq-answer { display: none; padding-bottom: 20px; }
.faq-item.open .faq-answer { display: block; }
.faq-answer p { color: var(--text-muted); font-size: 14px; line-height: 1.7; }

/* ── CTA ── */
.cta {
  background: linear-gradient(135deg, rgba(124,106,247,0.15) 0%, rgba(96,165,250,0.08) 100%);
  border-top: 1px solid var(--border); border-bottom: 1px solid var(--border);
}
.cta-inner { text-align: center; }
.cta h2 { font-size: clamp(24px, 4vw, 36px); font-weight: 800; margin-bottom: 12px; }
.cta p { color: var(--text-muted); font-size: 16px; margin-bottom: 32px; }

/* ── Footer ── */
.footer { background: var(--bg); padding: 60px 0 0; }
.footer-inner { display: flex; gap: 60px; padding-bottom: 48px; }
.footer-brand { flex: 1; }
.footer-brand .logo { margin-bottom: 12px; }
.footer-brand p { color: var(--text-muted); font-size: 14px; }
.footer-links { display: flex; gap: 60px; }
.footer-col { display: flex; flex-direction: column; gap: 10px; }
.footer-col h4 { font-size: 13px; font-weight: 700; color: var(--text); margin-bottom: 4px; }
.footer-col a { color: var(--text-muted); text-decoration: none; font-size: 14px; transition: color .2s; }
.footer-col a:hover { color: var(--text); }
.footer-bottom {
  border-top: 1px solid var(--border); padding: 20px 0;
}
.footer-bottom p { color: var(--text-muted); font-size: 13px; text-align: center; }

/* ── Customer Service ── */
.cs-fab {
  position: fixed; bottom: 32px; right: 32px; z-index: 200;
  width: 60px; height: 60px; border-radius: 50%;
  background: var(--accent); box-shadow: 0 4px 24px var(--accent-glow);
  display: flex; flex-direction: column; align-items: center; justify-content: center;
  cursor: pointer; transition: transform .2s, box-shadow .2s;
  gap: 2px;
}
.cs-fab:hover { transform: scale(1.08); box-shadow: 0 6px 32px var(--accent-glow); }
.cs-fab-icon { font-size: 22px; line-height: 1; }
.cs-fab-label { font-size: 10px; font-weight: 700; color: #fff; }

.cs-overlay {
  display: none; position: fixed; inset: 0; z-index: 199;
  background: rgba(0,0,0,0.5);
}
.cs-overlay.active { display: block; }

.cs-panel {
  position: fixed; bottom: 104px; right: 32px; z-index: 200;
  width: 320px; background: #16162a; border: 1px solid var(--border-hover);
  border-radius: var(--radius-lg); box-shadow: 0 20px 60px rgba(0,0,0,0.5);
  transform: translateY(20px) scale(0.95); opacity: 0;
  pointer-events: none; transition: all .25s cubic-bezier(.34,1.56,.64,1);
}
.cs-panel.active { transform: translateY(0) scale(1); opacity: 1; pointer-events: all; }
.cs-panel-header {
  display: flex; justify-content: space-between; align-items: center;
  padding: 16px 20px; border-bottom: 1px solid var(--border);
  font-weight: 700; font-size: 15px;
}
.cs-close {
  background: none; border: none; color: var(--text-muted); cursor: pointer;
  font-size: 16px; padding: 4px; transition: color .2s;
}
.cs-close:hover { color: var(--text); }
.cs-panel-body { padding: 20px; }
.cs-tip { color: var(--text-muted); font-size: 13px; margin-bottom: 16px; text-align: center; }
.cs-wechat-id {
  display: flex; align-items: center; justify-content: space-between;
  background: rgba(255,255,255,0.04); border: 1px solid var(--border);
  border-radius: 8px; padding: 10px 14px; margin-bottom: 12px;
}
.cs-wechat-id span { font-family: monospace; font-size: 14px; font-weight: 600; color: var(--text); }
.copy-wechat-btn {
  padding: 4px 12px; border-radius: 6px; font-size: 12px; font-weight: 600;
  background: rgba(124,106,247,0.15); border: 1px solid rgba(124,106,247,0.3);
  color: var(--accent2); cursor: pointer; transition: all .2s; white-space: nowrap;
}
.copy-wechat-btn:hover { background: rgba(124,106,247,0.25); }
.cs-divider {
  text-align: center; color: var(--text-muted); font-size: 12px;
  margin: 14px 0; position: relative;
}
.cs-divider::before, .cs-divider::after {
  content: ''; position: absolute; top: 50%; width: 35%; height: 1px;
  background: var(--border);
}
.cs-divider::before { left: 0; }
.cs-divider::after { right: 0; }
.cs-qr-img {
  display: block; width: 160px; height: 160px; margin: 0 auto;
  border-radius: 10px; object-fit: contain;
}

/* ── Toast ── */
.toast {
  position: fixed; bottom: 100px; left: 50%; transform: translateX(-50%) translateY(20px);
  background: #1e1e3a; border: 1px solid var(--border-hover); color: var(--text);
  padding: 10px 22px; border-radius: 100px; font-size: 14px; font-weight: 500;
  opacity: 0; pointer-events: none; transition: all .3s; z-index: 300;
  white-space: nowrap;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

/* ── Responsive ── */
@media (max-width: 900px) {
  .features-grid, .models-grid, .pricing-grid { grid-template-columns: 1fr; }
  .pricing-card--featured { transform: none; }
  .nav-links { display: none; }
  .hero-stats { flex-direction: column; gap: 16px; padding: 24px; }
  .stat-divider { width: 80px; height: 1px; }
  .footer-inner { flex-direction: column; gap: 32px; }
  .footer-links { flex-wrap: wrap; gap: 32px; }
  .cs-panel { right: 16px; left: 16px; width: auto; bottom: 96px; }
  .cs-fab { bottom: 24px; right: 24px; }
}