/* ============================================================
   大黄AI知识库官网 — 全局样式
   Design System: Dylanbrouwer / Cinematic Chrome
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Barlow+Condensed:wght@400;600;700;800;900&family=Plus+Jakarta+Sans:wght@400;500;600&family=IBM+Plex+Mono:wght@400;500;600&display=swap');

/* ── 设计令牌 ──────────────────────────────────────────────── */
:root {
  --obsidian:   #161616;
  --graphite:   #3c3a3e;
  --slate:      #7b7a7c;
  --ash:        #a2a2a2;
  --mist:       #c9c7cc;
  --fog:        #f1f1f1;
  --paper:      #f8f8f8;
  --bone:       #ffffff;
  --ember:      #ff4c24;
  --tangerine:  #ff6436;

  --font-display: 'Barlow Condensed', sans-serif;
  --font-body:    'Plus Jakarta Sans', sans-serif;
  --font-mono:    'IBM Plex Mono', monospace;

  --radius: 14.4px;

  --chrome-grad: linear-gradient(
    180deg,
    #000000 0%,
    #6e6c70 25%,
    #b9b7bb 50%,
    #dcd6d6 75%,
    #f1f1f1 100%
  );
}

/* ── Reset ─────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; font-size: 16px; }
body {
  font-family: var(--font-body);
  background: var(--bone);
  color: var(--graphite);
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a  { text-decoration: none; color: inherit; }
button { cursor: pointer; font-family: inherit; border: none; background: none; }

/* ── 导航 ──────────────────────────────────────────────────── */
.nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 48px;
  height: 64px;
  transition: background 0.3s, backdrop-filter 0.3s;
}
.nav.scrolled {
  background: rgba(241,241,241,0.88);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(60,58,62,0.1);
}
.nav-logo {
  display: flex;
  align-items: center;
  gap: 10px;
}
.nav-logo img {
  height: 36px;
  width: 36px;
  object-fit: contain;
}
.nav-logo-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.02em;
  color: var(--bone);
  transition: color 0.3s;
}
.nav.scrolled .nav-logo-name { color: var(--graphite); }

.nav-links {
  display: flex;
  align-items: center;
  gap: 32px;
  list-style: none;
}
.nav-links a {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: rgba(255,255,255,0.7);
  transition: color 0.2s;
}
.nav-links a:hover { color: var(--bone); }
.nav.scrolled .nav-links a { color: var(--slate); }
.nav.scrolled .nav-links a:hover { color: var(--graphite); }
.nav-links a.active { color: var(--bone); }
.nav.scrolled .nav-links a.active { color: var(--graphite); }

.nav-right {
  display: flex;
  align-items: center;
  gap: 16px;
}
.btn-demo {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 8px 18px;
  border: 1px solid rgba(255,255,255,0.5);
  border-radius: var(--radius);
  color: var(--bone);
  background: transparent;
  transition: all 0.2s;
}
.btn-demo:hover {
  border-color: var(--bone);
  background: rgba(255,255,255,0.08);
}
.nav.scrolled .btn-demo {
  border-color: var(--graphite);
  color: var(--graphite);
}
.nav.scrolled .btn-demo:hover {
  background: var(--graphite);
  color: var(--bone);
}

.lang-toggle {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ash);
  cursor: pointer;
  transition: color 0.2s;
  padding: 4px 8px;
  border: 1px solid transparent;
  border-radius: 6px;
}
.lang-toggle:hover { color: var(--bone); border-color: rgba(255,255,255,0.2); }
.nav.scrolled .lang-toggle { color: var(--slate); }
.nav.scrolled .lang-toggle:hover { color: var(--graphite); border-color: var(--mist); }

/* ── Hero ──────────────────────────────────────────────────── */
.hero {
  min-height: 100vh;
  background: var(--obsidian);
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 100px 48px 80px;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse 80% 60% at 50% 20%, rgba(255,76,36,0.04) 0%, transparent 70%);
  pointer-events: none;
}

.hero-eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--ember);
  margin-bottom: 24px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.hero-eyebrow::before {
  content: '';
  display: inline-block;
  width: 24px;
  height: 1px;
  background: var(--ember);
}

.hero-headline {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(72px, 10vw, 144px);
  line-height: 0.88;
  letter-spacing: -0.02em;
  text-align: center;
  background: var(--chrome-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 32px;
  max-width: 900px;
}

.hero-sub {
  font-family: var(--font-body);
  font-size: 17px;
  font-weight: 400;
  line-height: 1.7;
  color: var(--ash);
  text-align: center;
  max-width: 620px;
  margin-bottom: 44px;
}

.hero-cta {
  display: flex;
  gap: 16px;
  margin-bottom: 72px;
}
.btn-primary {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 14px 32px;
  border: 1px solid var(--ember);
  border-radius: var(--radius);
  color: var(--ember);
  background: transparent;
  transition: all 0.2s;
}
.btn-primary:hover {
  background: var(--ember);
  color: var(--bone);
}
.btn-ghost {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  padding: 14px 32px;
  border: 1px solid rgba(255,255,255,0.2);
  border-radius: var(--radius);
  color: rgba(255,255,255,0.6);
  background: transparent;
  transition: all 0.2s;
}
.btn-ghost:hover {
  border-color: rgba(255,255,255,0.5);
  color: var(--bone);
}

/* Browser frame */
.browser-frame {
  width: 100%;
  max-width: 960px;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1.5px solid var(--ember);
  box-shadow: 0 40px 80px rgba(0,0,0,0.6), 0 0 0 1px rgba(255,76,36,0.15);
  position: relative;
}
.browser-bar {
  background: #222;
  padding: 10px 16px;
  display: flex;
  align-items: center;
  gap: 8px;
  border-bottom: 1px solid #333;
}
.browser-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
}
.browser-dot-r { background: #ff5f57; }
.browser-dot-y { background: #febc2e; }
.browser-dot-g { background: #28c840; }
.browser-url {
  margin-left: 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ash);
  background: #2a2a2a;
  padding: 3px 12px;
  border-radius: 5px;
  flex: 1;
  max-width: 280px;
}
.browser-frame img {
  width: 100%;
  display: block;
  transition: transform 0.4s ease;
}
.browser-frame:hover img { transform: scale(1.01); }

.hero-meta {
  position: absolute;
  bottom: 48px;
  left: 48px;
  display: flex;
  flex-direction: column;
  gap: 3px;
}
.hero-meta span {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  color: var(--slate);
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

/* ── Section common ────────────────────────────────────────── */
.section { padding: 96px 48px; }
.section-dark { background: var(--obsidian); }
.section-light { background: var(--bone); }
.section-paper { background: var(--paper); }

.section-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--ember);
  margin-bottom: 16px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.section-label::before {
  content: '';
  width: 20px; height: 1px;
  background: var(--ember);
}

.section-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(42px, 5vw, 60px);
  line-height: 1.0;
  letter-spacing: -0.02em;
  color: var(--graphite);
  margin-bottom: 20px;
}
.section-title.on-dark {
  background: var(--chrome-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.section-desc {
  font-size: 17px;
  line-height: 1.7;
  color: var(--slate);
  max-width: 560px;
  margin-bottom: 64px;
}
.section-desc.on-dark { color: var(--ash); }

.section-ghost-title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(64px, 9vw, 120px);
  line-height: 1.0;
  letter-spacing: -0.02em;
  color: var(--fog);
  margin-bottom: -24px;
  pointer-events: none;
  user-select: none;
}

/* ── What is AI KB (compare) ───────────────────────────────── */
.compare-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  max-width: 900px;
}
.compare-card {
  padding: 36px;
  border-radius: var(--radius);
  border: 1px solid var(--mist);
  background: var(--paper);
}
.compare-card.highlighted {
  background: var(--obsidian);
  border-color: var(--ember);
}
.compare-card-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ash);
  margin-bottom: 14px;
}
.compare-card.highlighted .compare-card-label { color: var(--ember); }
.compare-card-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 28px;
  color: var(--graphite);
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}
.compare-card.highlighted .compare-card-title { color: var(--bone); }
.compare-card-body {
  font-size: 15px;
  line-height: 1.7;
  color: var(--slate);
}
.compare-card.highlighted .compare-card-body { color: var(--ash); }
.compare-card-pain {
  display: flex;
  align-items: flex-start;
  gap: 8px;
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--fog);
  font-size: 13px;
  color: var(--ash);
  font-style: italic;
}
.compare-card.highlighted .compare-card-pain { border-color: rgba(255,255,255,0.08); color: var(--slate); }
.pain-icon { flex-shrink: 0; color: var(--mist); font-style: normal; }
.compare-card.highlighted .pain-icon { color: var(--ember); }

/* ── Features grid ─────────────────────────────────────────── */
.features-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}
.feature-card {
  padding: 28px 24px;
  border: 1px solid var(--mist);
  border-radius: var(--radius);
  background: var(--paper);
  transition: border-color 0.2s;
}
.feature-card:hover { border-color: var(--graphite); }
.feature-icon {
  font-size: 24px;
  margin-bottom: 16px;
  display: block;
  width: 44px; height: 44px;
  background: var(--fog);
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
}
.feature-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 20px;
  color: var(--graphite);
  letter-spacing: -0.01em;
  margin-bottom: 8px;
}
.feature-desc {
  font-size: 14px;
  line-height: 1.6;
  color: var(--slate);
}

/* ── Screenshots ───────────────────────────────────────────── */
.screenshots-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
}
.screenshot-item {
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid rgba(255,255,255,0.08);
  transition: border-color 0.3s, transform 0.3s;
  position: relative;
}
.screenshot-item:hover {
  border-color: var(--ember);
  transform: translateY(-4px);
}
.screenshot-item img { width: 100%; display: block; }
.screenshot-caption {
  position: absolute;
  bottom: 0; left: 0; right: 0;
  padding: 20px 20px 16px;
  background: linear-gradient(0deg, rgba(22,22,22,0.9) 0%, transparent 100%);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ash);
}

/* ── Video Section ─────────────────────────────────────────── */
.video-container {
  max-width: 900px;
  margin: 0 auto;
}
.video-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 20px;
}
.video-tab {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 7px 18px;
  border: 1px solid rgba(255,255,255,0.15);
  border-radius: var(--radius);
  color: var(--ash);
  transition: all 0.2s;
}
.video-tab:hover { border-color: rgba(255,255,255,0.4); color: var(--bone); }
.video-tab.active { border-color: var(--ember); color: var(--ember); }

.video-player {
  width: 100%;
  aspect-ratio: 16/9;
  background: #111;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1.5px solid rgba(255,76,36,0.3);
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
}
.video-player video {
  width: 100%;
  height: 100%;
  object-fit: cover;
}
.video-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  color: var(--slate);
}
.video-placeholder-icon {
  width: 56px; height: 56px;
  border: 1.5px solid rgba(255,76,36,0.4);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--ember);
  font-size: 20px;
}
.video-placeholder p {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

/* ── Pricing ───────────────────────────────────────────────── */
.pricing-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 12px;
}
.pricing-card {
  padding: 28px 20px;
  border: 1px solid var(--mist);
  border-radius: var(--radius);
  background: var(--paper);
  text-align: center;
  transition: all 0.2s;
  position: relative;
}
.pricing-card:hover {
  border-color: var(--graphite);
  transform: translateY(-4px);
}
.pricing-card.featured {
  border-color: var(--ember);
  background: var(--obsidian);
}
.pricing-badge {
  position: absolute;
  top: -11px;
  left: 50%;
  transform: translateX(-50%);
  background: var(--ember);
  color: var(--bone);
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 3px 12px;
  border-radius: 20px;
  white-space: nowrap;
}
.pricing-years {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 32px;
  color: var(--graphite);
  letter-spacing: -0.01em;
  margin-bottom: 4px;
}
.pricing-card.featured .pricing-years { color: var(--bone); }
.pricing-years-label {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ash);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  margin-bottom: 20px;
}
.pricing-price {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 28px;
  color: var(--graphite);
  letter-spacing: -0.01em;
}
.pricing-card.featured .pricing-price { color: var(--bone); }
.pricing-per {
  font-size: 13px;
  color: var(--ash);
  margin-top: 4px;
  line-height: 1.4;
}
.pricing-discount {
  display: inline-block;
  background: var(--tangerine);
  color: var(--bone);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 20px;
  margin-top: 12px;
}

/* ── CTA Strip ─────────────────────────────────────────────── */
.cta-strip {
  background: var(--obsidian);
  border-top: 1px solid rgba(255,255,255,0.06);
  border-bottom: 1px solid rgba(255,255,255,0.06);
  padding: 80px 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 48px;
}
.cta-strip-title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(36px, 4vw, 54px);
  line-height: 1.0;
  letter-spacing: -0.02em;
  background: var(--chrome-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.cta-strip-sub {
  font-size: 15px;
  color: var(--slate);
  margin-top: 8px;
  line-height: 1.6;
}

/* ── Footer ────────────────────────────────────────────────── */
.footer {
  background: var(--obsidian);
  border-top: 1px solid rgba(255,255,255,0.06);
  padding: 64px 48px 40px;
}
.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.5fr;
  gap: 48px;
  margin-bottom: 48px;
}
.footer-brand { display: flex; flex-direction: column; gap: 16px; }
.footer-logo {
  display: flex;
  align-items: center;
  gap: 10px;
}
.footer-logo img { width: 32px; height: 32px; object-fit: contain; }
.footer-logo-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  color: var(--bone);
  letter-spacing: 0.02em;
}
.footer-tagline {
  font-size: 13px;
  line-height: 1.7;
  color: var(--slate);
  max-width: 260px;
}
.footer-col-title {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ash);
  margin-bottom: 16px;
}
.footer-links { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.footer-links a {
  font-size: 14px;
  color: var(--slate);
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--bone); }
.footer-contact-email {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ash);
  margin-bottom: 20px;
  transition: color 0.2s;
}
.footer-contact-email:hover { color: var(--bone); }
.footer-qr {
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.footer-qr img {
  width: 160px; height: 160px;
  object-fit: contain;
  border-radius: 8px;
  background: var(--bone);
  padding: 6px;
}
.footer-qr-label {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--slate);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}
.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 32px;
  border-top: 1px solid rgba(255,255,255,0.06);
}
.footer-copy {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--slate);
  letter-spacing: 0.04em;
}
.footer-icp {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--slate);
}

/* ── Modal ─────────────────────────────────────────────────── */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(22,22,22,0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 999;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s;
}
.modal-overlay.open {
  opacity: 1;
  pointer-events: all;
}
.modal {
  background: var(--bone);
  border-radius: calc(var(--radius) * 1.5);
  padding: 48px;
  width: 100%;
  max-width: 540px;
  position: relative;
  transform: translateY(16px);
  transition: transform 0.25s;
}
.modal-overlay.open .modal {
  transform: translateY(0);
}
.modal-close {
  position: absolute;
  top: 20px; right: 20px;
  width: 32px; height: 32px;
  border-radius: 50%;
  background: var(--fog);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 16px;
  color: var(--slate);
  cursor: pointer;
  transition: all 0.15s;
  border: none;
}
.modal-close:hover { background: var(--mist); color: var(--graphite); }
.modal-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ember);
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.modal-label::before { content: ''; width: 16px; height: 1px; background: var(--ember); }
.modal-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 32px;
  letter-spacing: -0.02em;
  color: var(--graphite);
  margin-bottom: 8px;
  line-height: 1.1;
}
.modal-sub {
  font-size: 14px;
  color: var(--slate);
  margin-bottom: 32px;
  line-height: 1.6;
}
.form-group { margin-bottom: 16px; }
.form-label {
  display: block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ash);
  margin-bottom: 6px;
}
.form-input {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid var(--mist);
  border-radius: var(--radius);
  font-family: var(--font-body);
  font-size: 15px;
  color: var(--graphite);
  background: var(--paper);
  outline: none;
  transition: border-color 0.2s;
}
.form-input:focus { border-color: var(--graphite); }
.form-input::placeholder { color: var(--mist); }
.form-submit {
  width: 100%;
  padding: 14px;
  background: var(--graphite);
  color: var(--bone);
  border: none;
  border-radius: var(--radius);
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
  transition: background 0.2s;
  margin-top: 8px;
}
.form-submit:hover { background: var(--obsidian); }
.form-submit:disabled { background: var(--mist); cursor: not-allowed; }

.modal-divider {
  display: flex;
  align-items: center;
  gap: 12px;
  margin: 24px 0;
}
.modal-divider::before, .modal-divider::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--fog);
}
.modal-divider span {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--mist);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  white-space: nowrap;
}

.modal-contacts {
  display: flex;
  gap: 24px;
  align-items: flex-start;
}
.modal-wechat { display: flex; flex-direction: column; align-items: center; gap: 6px; }
.modal-wechat img {
  width: 160px; height: 160px;
  border-radius: 10px;
  border: 1px solid var(--fog);
}
.modal-wechat-label {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--ash);
  letter-spacing: 0.05em;
  text-align: center;
}
.modal-email-link {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--slate);
  padding: 12px 16px;
  border: 1px solid var(--fog);
  border-radius: var(--radius);
  transition: all 0.2s;
  align-self: flex-start;
}
.modal-email-link:hover { border-color: var(--graphite); color: var(--graphite); }

.form-success {
  display: none;
  text-align: center;
  padding: 24px 0;
}
.form-success.show { display: block; }
.form-success-icon {
  width: 52px; height: 52px;
  border: 1.5px solid var(--ember);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 22px;
  color: var(--ember);
  margin: 0 auto 16px;
}
.form-success h3 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 24px;
  color: var(--graphite);
  margin-bottom: 8px;
}
.form-success p { font-size: 14px; color: var(--slate); line-height: 1.6; }

/* ── FAQ accordion ─────────────────────────────────────────── */
.faq-list { max-width: 760px; }
.faq-item {
  border-bottom: 1px solid var(--fog);
}
.faq-question {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 24px 0;
  cursor: pointer;
  gap: 24px;
}
.faq-question-text {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 20px;
  color: var(--graphite);
  letter-spacing: -0.01em;
  line-height: 1.3;
}
.faq-toggle {
  width: 28px; height: 28px;
  border: 1px solid var(--mist);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 16px;
  color: var(--slate);
  transition: all 0.2s;
}
.faq-item.open .faq-toggle {
  border-color: var(--ember);
  color: var(--ember);
  transform: rotate(45deg);
}
.faq-answer {
  font-size: 15px;
  line-height: 1.75;
  color: var(--slate);
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.35s ease, padding 0.2s;
  padding: 0;
}
.faq-item.open .faq-answer {
  max-height: 600px;
  padding-bottom: 24px;
}

/* ── Distillation quote ─────────────────────────────────────── */
.distill-quote {
  max-width: 800px;
  margin: 0 auto;
  text-align: center;
}
.distill-quote blockquote {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(22px, 3vw, 32px);
  line-height: 1.4;
  letter-spacing: -0.01em;
  color: var(--mist);
  font-style: normal;
  position: relative;
  padding: 0 48px;
}
.distill-quote blockquote::before {
  content: '"';
  position: absolute;
  top: -20px; left: 0;
  font-size: 80px;
  color: rgba(255,76,36,0.15);
  font-family: var(--font-display);
  font-weight: 900;
  line-height: 1;
}

/* ── Page hero (inner pages) ───────────────────────────────── */
.page-hero {
  background: var(--obsidian);
  padding: 140px 48px 96px;
}
.page-hero-title {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: clamp(54px, 8vw, 108px);
  line-height: 0.9;
  letter-spacing: -0.02em;
  background: var(--chrome-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 24px;
  max-width: 800px;
}
.page-hero-sub {
  font-size: 18px;
  line-height: 1.6;
  color: var(--ash);
  max-width: 560px;
}

/* ── Formats grid ──────────────────────────────────────────── */
.formats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
  gap: 12px;
}
.format-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 14px 18px;
  border: 1px solid var(--fog);
  border-radius: var(--radius);
  background: var(--paper);
}
.format-ext {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  color: var(--bone);
  background: var(--graphite);
  padding: 3px 8px;
  border-radius: 5px;
  min-width: 52px;
  text-align: center;
  letter-spacing: 0.05em;
}
.format-desc {
  font-size: 13px;
  color: var(--slate);
  line-height: 1.4;
}

/* ── Stats ─────────────────────────────────────────────────── */
.stats-row {
  display: flex;
  gap: 48px;
  flex-wrap: wrap;
}
.stat-item { display: flex; flex-direction: column; gap: 4px; }
.stat-number {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 52px;
  letter-spacing: -0.03em;
  line-height: 1;
  background: var(--chrome-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.stat-label {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--slate);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

/* ── Utility ────────────────────────────────────────────────── */
.container { max-width: 1200px; margin: 0 auto; }
.text-ember { color: var(--ember); }
.mt-48 { margin-top: 48px; }
.mb-0 { margin-bottom: 0; }

/* ── Responsive ─────────────────────────────────────────────── */
@media (max-width: 1024px) {
  .features-grid { grid-template-columns: repeat(2, 1fr); }
  .pricing-grid  { grid-template-columns: repeat(3, 1fr); }
  .footer-grid   { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .nav { padding: 0 24px; }
  .nav-links { display: none; }
  .section { padding: 72px 24px; }
  .hero { padding: 100px 24px 64px; }
  .hero-meta { left: 24px; bottom: 24px; }
  .compare-grid { grid-template-columns: 1fr; }
  .features-grid { grid-template-columns: 1fr 1fr; }
  .screenshots-grid { grid-template-columns: 1fr; }
  .pricing-grid { grid-template-columns: repeat(2, 1fr); }
  .footer-grid { grid-template-columns: 1fr; }
  .cta-strip { flex-direction: column; align-items: flex-start; }
  .modal { padding: 32px 24px; }
  .modal-contacts { flex-direction: column; }
}
@media (max-width: 480px) {
  .hero-headline { font-size: 60px; }
  .features-grid { grid-template-columns: 1fr; }
  .pricing-grid  { grid-template-columns: 1fr 1fr; }
  .page-hero { padding: 100px 24px 64px; }
}

/* ── Scroll animation ───────────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }

/* ── Inner pages: page-hero extensions ──────────────────────── */
.page-hero-sm { padding-bottom: 72px; }
.page-hero-desc {
  font-size: 17px;
  line-height: 1.75;
  color: var(--ash);
  max-width: 640px;
  margin-bottom: 36px;
}
.nav-links a.active { color: var(--graphite); }

/* ── Product page: feature rows ─────────────────────────────── */
.prod-features {
  display: flex;
  flex-direction: column;
  gap: 96px;
  margin-top: 72px;
}
.prod-feature-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: center;
}
.prod-feature-row-alt .prod-feature-content { order: 2; }
.prod-feature-row-alt .prod-feature-visual  { order: 1; }

.prod-feature-num {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.16em;
  color: var(--ember);
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 10px;
}
.prod-feature-num::after {
  content: '';
  flex: 0 0 32px;
  height: 1px;
  background: var(--ember);
  opacity: 0.4;
}
.prod-feature-name {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(28px, 3vw, 40px);
  letter-spacing: -0.02em;
  line-height: 1.05;
  color: var(--graphite);
  margin-bottom: 16px;
}
.prod-feature-body {
  font-size: 15px;
  line-height: 1.75;
  color: var(--slate);
  margin-bottom: 20px;
}
.prod-feature-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.prod-feature-list li {
  font-size: 14px;
  color: var(--slate);
  padding-left: 18px;
  position: relative;
  line-height: 1.5;
}
.prod-feature-list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 8px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--ember);
  opacity: 0.7;
}

/* ── Product page: visual areas ─────────────────────────────── */
.prod-feature-visual {
  background: var(--paper);
  border: 1px solid var(--fog);
  border-radius: calc(var(--radius) * 2);
  padding: 40px;
  min-height: 280px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 20px;
}

/* Format tags grid */
.format-tag {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.06em;
  padding: 6px 14px;
  border-radius: 20px;
  border: 1px solid transparent;
}
.tag-red    { background: rgba(255,76,36,0.08);  color: #d63000; border-color: rgba(255,76,36,0.2); }
.tag-blue   { background: rgba(37,99,235,0.08);  color: #1d4ed8; border-color: rgba(37,99,235,0.2); }
.tag-green  { background: rgba(22,163,74,0.08);  color: #15803d; border-color: rgba(22,163,74,0.2); }
.tag-orange { background: rgba(234,88,12,0.08);  color: #c2410c; border-color: rgba(234,88,12,0.2); }
.tag-purple { background: rgba(109,40,217,0.08); color: #6d28d9; border-color: rgba(109,40,217,0.2); }

.formats-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  justify-content: center;
}
.formats-caption {
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--mist);
  letter-spacing: 0.06em;
  text-transform: uppercase;
  text-align: center;
}

/* Stats block */
.stat-block {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  flex: 1;
}
.stat-divider {
  width: 1px;
  height: 48px;
  background: var(--mist);
  align-self: center;
}
.prod-feature-visual .stat-block,
.prod-feature-visual .stat-divider {
  display: flex;
}
.prod-feature-visual .stat-number {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 52px;
  letter-spacing: -0.03em;
  line-height: 1;
  background: var(--chrome-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.prod-feature-visual .stat-label {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ash);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  text-align: center;
}
.prod-feature-visual.stat-row {
  flex-direction: row;
}
.chrome-text {
  font-family: var(--font-display);
  font-weight: 900;
  font-size: 52px;
  letter-spacing: -0.03em;
  line-height: 1;
  background: var(--chrome-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Retrieval diagram */
.retrieval-diagram {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
  width: 100%;
}
.retrieval-branch {
  display: flex;
  gap: 16px;
  margin-bottom: 8px;
}
.retrieval-merge {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
}
.retrieval-node {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.04em;
  padding: 10px 20px;
  border-radius: 8px;
  text-align: center;
  min-width: 120px;
}
.node-vec   { background: rgba(37,99,235,0.1);   color: #1d4ed8; border: 1px solid rgba(37,99,235,0.2); }
.node-kw    { background: rgba(22,163,74,0.1);   color: #15803d; border: 1px solid rgba(22,163,74,0.2); }
.node-rrf   { background: rgba(109,40,217,0.1);  color: #6d28d9; border: 1px solid rgba(109,40,217,0.2); }
.node-rerank{ background: rgba(234,88,12,0.1);   color: #c2410c; border: 1px solid rgba(234,88,12,0.2); }
.node-ans   { background: rgba(22,22,22,0.06);   color: var(--graphite); border: 1px solid var(--mist); }
.retrieval-arrow {
  font-size: 18px;
  color: var(--mist);
  line-height: 1.2;
}

/* Permission visual */
.permission-visual {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
  width: 100%;
}
.perm-level {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 16px;
  letter-spacing: 0.02em;
  padding: 12px 32px;
  border-radius: 10px;
  width: 220px;
  justify-content: center;
}
.perm-icon { font-size: 18px; }
.perm-arrow { font-size: 20px; color: var(--mist); line-height: 1.1; }
.perm-l1 { background: rgba(22,22,22,0.06);   color: var(--graphite); }
.perm-l2 { background: rgba(37,99,235,0.08);  color: #1d4ed8; }
.perm-l3 { background: rgba(22,163,74,0.08);  color: #15803d; }
.perm-l4 { background: rgba(255,76,36,0.08);  color: #d63000; }

/* ── Deploy section ──────────────────────────────────────────── */
.deploy-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
  margin-top: 56px;
}
.deploy-card {
  background: var(--bone);
  border: 1px solid var(--fog);
  border-radius: calc(var(--radius) * 1.5);
  padding: 36px 28px;
  transition: border-color 0.2s, transform 0.2s;
}
.deploy-card:hover { border-color: var(--mist); transform: translateY(-2px); }
.deploy-icon { font-size: 32px; margin-bottom: 16px; }
.deploy-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 22px;
  letter-spacing: -0.01em;
  color: var(--graphite);
  margin-bottom: 10px;
}
.deploy-body { font-size: 14px; line-height: 1.7; color: var(--slate); }

/* ── Integration section ─────────────────────────────────────── */
.integ-grid {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 48px;
  align-items: center;
  margin-top: 56px;
}
.integ-center {
  display: flex;
  justify-content: center;
  align-items: center;
}
.integ-core {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  background: var(--obsidian);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 8px;
  box-shadow: 0 0 0 12px rgba(22,22,22,0.06), 0 0 0 24px rgba(22,22,22,0.03);
}
.integ-core img { width: 48px; height: 48px; object-fit: contain; }
.integ-core-label {
  font-family: var(--font-display);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--ash);
  text-align: center;
  line-height: 1.3;
}
.integ-satellites {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
}
.integ-tag {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.02em;
  padding: 10px 22px;
  border: 1px solid var(--fog);
  border-radius: 100px;
  color: var(--graphite);
  background: var(--paper);
}
.integ-note {
  margin-top: 48px;
  padding: 24px 28px;
  background: var(--paper);
  border-left: 3px solid var(--ember);
  border-radius: 0 var(--radius) var(--radius) 0;
}
.integ-note-text {
  font-size: 14px;
  line-height: 1.7;
  color: var(--slate);
}
.integ-note-text strong { color: var(--graphite); }

/* ── Scenarios section ───────────────────────────────────────── */
.scenarios-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  margin-top: 56px;
}
.scenario-card {
  padding: 28px 22px;
  border: 1px solid var(--fog);
  border-radius: calc(var(--radius) * 1.5);
  background: var(--bone);
  transition: border-color 0.2s, transform 0.2s;
}
.scenario-card:hover { border-color: var(--mist); transform: translateY(-2px); }
.scenario-icon { font-size: 28px; margin-bottom: 14px; }
.scenario-name {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 18px;
  letter-spacing: -0.01em;
  color: var(--graphite);
  margin-bottom: 10px;
  line-height: 1.3;
}
.scenario-body { font-size: 13px; line-height: 1.7; color: var(--slate); }

/* ── FAQ page specific ───────────────────────────────────────── */
.container-narrow { max-width: 800px; margin: 0 auto; }

/* Fix: make .faq-question a proper full-width button */
.faq-question {
  width: 100%;
  background: none;
  border: none;
  text-align: left;
}
.faq-question-text {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 20px;
  color: var(--graphite);
  letter-spacing: -0.01em;
  line-height: 1.3;
  flex: 1;
}
.faq-arrow {
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  border: 1px solid var(--mist);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  transition: all 0.2s;
}
.faq-arrow::before,
.faq-arrow::after {
  content: '';
  position: absolute;
  background: var(--slate);
  border-radius: 2px;
  transition: transform 0.2s, background 0.2s;
}
.faq-arrow::before { width: 10px; height: 1.5px; }
.faq-arrow::after  { width: 1.5px; height: 10px; }
.faq-item.open .faq-arrow {
  border-color: var(--ember);
}
.faq-item.open .faq-arrow::before,
.faq-item.open .faq-arrow::after { background: var(--ember); }
.faq-item.open .faq-arrow::after { transform: rotate(90deg); }

.faq-answer { display: flex; flex-direction: column; gap: 12px; }
.faq-answer p { margin: 0; }

.faq-answer-subtitle {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ash);
  margin-top: 8px;
  margin-bottom: 4px;
}
.faq-format-grid {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.faq-format-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.04em;
  padding: 5px 12px;
  background: var(--paper);
  border: 1px solid var(--fog);
  border-radius: 6px;
  color: var(--graphite);
}
.faq-answer-list {
  padding-left: 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin: 4px 0;
}
.faq-answer-list li {
  font-size: 14px;
  line-height: 1.65;
  color: var(--slate);
}
.faq-answer-list li strong { color: var(--graphite); }

/* FAQ pricing table */
.faq-pricing-table {
  border: 1px solid var(--fog);
  border-radius: var(--radius);
  overflow: hidden;
  margin: 8px 0 12px;
}
.faq-pricing-head,
.faq-pricing-row {
  display: grid;
  grid-template-columns: 1fr 1fr 1.2fr 1.2fr;
  gap: 0;
}
.faq-pricing-head {
  background: var(--obsidian);
  padding: 12px 20px;
}
.faq-pricing-head span {
  font-family: var(--font-mono);
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--ash);
}
.faq-pricing-row {
  padding: 14px 20px;
  border-bottom: 1px solid var(--fog);
  align-items: center;
}
.faq-pricing-row:last-child { border-bottom: none; }
.faq-pricing-row span {
  font-size: 14px;
  color: var(--graphite);
  font-family: var(--font-body);
}
.faq-pricing-featured {
  background: rgba(255,76,36,0.04);
}
.faq-pricing-featured span { font-weight: 600; }
.faq-discount-badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  padding: 3px 10px;
  border-radius: 20px;
  background: var(--paper);
  border: 1px solid var(--fog);
  color: var(--slate);
}
.badge-hot {
  background: rgba(255,76,36,0.1);
  border-color: rgba(255,76,36,0.3);
  color: var(--ember);
}

/* FAQ bottom CTA */
.faq-more {
  margin-top: 72px;
  text-align: center;
  padding: 64px 48px;
  background: var(--obsidian);
  border-radius: calc(var(--radius) * 2);
}
.faq-more-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 32px;
  letter-spacing: -0.02em;
  background: var(--chrome-grad);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: 12px;
}
.faq-more-desc {
  font-size: 15px;
  color: var(--slate);
  margin-bottom: 32px;
  line-height: 1.6;
}
.faq-more-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* Screen-reader only */
.sr-only {
  position: absolute;
  width: 1px; height: 1px;
  padding: 0; margin: -1px;
  overflow: hidden;
  clip: rect(0,0,0,0);
  white-space: nowrap;
  border: 0;
}

/* ── Responsive additions ────────────────────────────────────── */
@media (max-width: 1024px) {
  .prod-feature-row { grid-template-columns: 1fr; gap: 40px; }
  .prod-feature-row-alt .prod-feature-content { order: 0; }
  .prod-feature-row-alt .prod-feature-visual  { order: 0; }
  .deploy-grid     { grid-template-columns: 1fr 1fr; }
  .scenarios-grid  { grid-template-columns: 1fr 1fr; }
  .integ-grid      { grid-template-columns: 1fr; }
  .integ-center    { display: none; }
}
@media (max-width: 768px) {
  .deploy-grid     { grid-template-columns: 1fr; }
  .scenarios-grid  { grid-template-columns: 1fr; }
  .prod-feature-visual { padding: 28px 20px; }
  .faq-more { padding: 48px 24px; }
  .faq-more-actions { flex-direction: column; align-items: center; }
  .faq-pricing-head,
  .faq-pricing-row { grid-template-columns: 1.2fr 1fr 1.2fr 1.2fr; padding: 12px 14px; }
}
@media (max-width: 480px) {
  .deploy-grid     { grid-template-columns: 1fr; }
  .scenarios-grid  { grid-template-columns: 1fr; }
}