/* === YANVI.AI — Dark Theme === */

:root {
  --bg: #0a0a0a;
  --bg-card: #141414;
  --bg-card-alt: #1a1a1a;
  --amber: #ff9600;
  --amber-dim: #cc7800;
  --teal: #01696f;
  --teal-light: #4f98a3;
  --white: #eeeeee;
  --muted: #999999;
  --faint: #555555;
  --border: #222222;
  --font: 'DM Sans', system-ui, sans-serif;
  --mono: 'JetBrains Mono', monospace;
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--white);
  line-height: 1.6;
  overflow-x: hidden;
}

/* Nav */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  background: rgba(10, 10, 10, 0.85);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}

.nav-inner {
  max-width: 900px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  color: var(--white);
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.02em;
}

.logo svg { color: var(--white); }

.nav-links {
  display: flex;
  gap: 20px;
}

.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: color 0.2s;
}

.nav-links a:hover { color: var(--white); }

/* Hero */
.hero {
  max-width: 900px;
  margin: 0 auto;
  padding: 140px 24px 60px;
  text-align: center;
}

.hero-badge {
  display: inline-block;
  padding: 6px 16px;
  background: rgba(255, 150, 0, 0.1);
  border: 1px solid rgba(255, 150, 0, 0.25);
  border-radius: 100px;
  font-size: 13px;
  font-weight: 500;
  color: var(--amber);
  margin-bottom: 24px;
}

.hero h1 {
  font-size: clamp(36px, 6vw, 56px);
  font-weight: 700;
  line-height: 1.1;
  margin-bottom: 16px;
  letter-spacing: -0.02em;
}

.hero-sub {
  font-size: clamp(16px, 2.5vw, 19px);
  color: var(--muted);
  max-width: 560px;
  margin: 0 auto 40px;
  line-height: 1.5;
}

.hero-stats {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  margin-bottom: 36px;
  flex-wrap: wrap;
}

.stat { text-align: center; }

.stat-num {
  display: block;
  font-size: 28px;
  font-weight: 700;
  color: var(--white);
  line-height: 1.2;
}

.stat-label {
  font-size: 12px;
  color: var(--faint);
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.stat-divider {
  width: 1px;
  height: 32px;
  background: var(--border);
}

.cta-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  background: var(--amber);
  color: #0a0a0a;
  text-decoration: none;
  font-weight: 600;
  font-size: 15px;
  border-radius: 8px;
  transition: background 0.2s, transform 0.15s;
}

.cta-btn:hover {
  background: var(--amber-dim);
  transform: translateY(-1px);
}

/* Video */
.video-section {
  max-width: 800px;
  margin: 0 auto;
  padding: 0 24px 80px;
}

.video-container {
  position: relative;
  width: 100%;
  padding-bottom: 56.25%;
  border-radius: 12px;
  overflow: hidden;
  border: 1px solid var(--border);
  background: #000;
}

.video-container iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}

/* Sections */
.section-inner {
  max-width: 900px;
  margin: 0 auto;
  padding: 80px 24px;
}

/* What */
.what {
  border-top: 1px solid var(--border);
}

.what h2 {
  font-size: clamp(28px, 4vw, 38px);
  font-weight: 700;
  margin-bottom: 16px;
  line-height: 1.2;
}

.what > .section-inner > p {
  color: var(--muted);
  font-size: 17px;
  max-width: 600px;
  margin-bottom: 48px;
}

.features {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 24px;
}

.feature {
  padding: 28px 24px;
  background: var(--bg-card);
  border-radius: 12px;
  border: 1px solid var(--border);
}

.feature-icon {
  font-size: 24px;
  margin-bottom: 12px;
}

.feature h3 {
  font-size: 16px;
  font-weight: 600;
  margin-bottom: 8px;
}

.feature p {
  font-size: 14px;
  color: var(--muted);
  line-height: 1.5;
}

/* Architecture */
.arch {
  border-top: 1px solid var(--border);
}

.arch h2 {
  font-size: clamp(28px, 4vw, 38px);
  font-weight: 700;
  margin-bottom: 8px;
}

.arch-sub {
  color: var(--muted);
  font-size: 17px;
  margin-bottom: 40px;
}

.tiers {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
}

.tier {
  width: 100%;
  max-width: 500px;
  padding: 24px 28px;
  border-radius: 12px;
  border: 1px solid var(--border);
  position: relative;
}

.tier-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--faint);
  margin-bottom: 4px;
}

.tier h3 {
  font-size: 18px;
  font-weight: 600;
  margin-bottom: 4px;
}

.tier p {
  font-size: 14px;
  color: var(--muted);
}

.tier-mac {
  background: rgba(140, 40, 220, 0.06);
  border-color: rgba(140, 40, 220, 0.2);
}

.tier-pi {
  background: rgba(1, 105, 111, 0.08);
  border-color: rgba(1, 105, 111, 0.3);
}

.tier-esp {
  background: rgba(255, 150, 0, 0.06);
  border-color: rgba(255, 150, 0, 0.2);
}

.tier-arrow {
  font-family: var(--mono);
  font-size: 12px;
  color: var(--faint);
  padding: 8px 0;
}

/* Builder */
.builder {
  border-top: 1px solid var(--border);
}

.builder h2 {
  font-size: clamp(28px, 4vw, 38px);
  font-weight: 700;
  margin-bottom: 12px;
}

.builder > .section-inner > p {
  color: var(--muted);
  font-size: 17px;
  margin-bottom: 36px;
}

.timeline-mini {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.tl-item {
  display: flex;
  align-items: baseline;
  gap: 16px;
  font-size: 15px;
  color: var(--muted);
  padding-left: 16px;
  border-left: 2px solid var(--border);
}

.tl-day {
  font-weight: 600;
  color: var(--amber);
  font-size: 13px;
  min-width: 52px;
  flex-shrink: 0;
}

/* Bottom CTA */
.bottom-cta {
  border-top: 1px solid var(--border);
  text-align: center;
  padding: 80px 24px;
}

.bottom-cta h2 {
  font-size: clamp(24px, 3.5vw, 32px);
  font-weight: 700;
  margin-bottom: 8px;
}

.bottom-cta > p {
  color: var(--muted);
  font-size: 17px;
  margin-bottom: 28px;
}

.links-row {
  display: flex;
  justify-content: center;
  gap: 24px;
  flex-wrap: wrap;
  margin-bottom: 40px;
}

.links-row a {
  color: var(--teal-light);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: color 0.2s;
}

.links-row a:hover { color: var(--white); }

.company {
  font-size: 13px;
  color: var(--faint);
}

/* Mobile */
@media (max-width: 600px) {
  .hero { padding: 120px 20px 40px; }
  .hero-stats { gap: 16px; }
  .stat-num { font-size: 22px; }
  .stat-divider { height: 24px; }
  .features { grid-template-columns: 1fr; }
  .section-inner { padding: 60px 20px; }
  .nav-links { gap: 14px; }
  .nav-links a { font-size: 13px; }
  .tier { padding: 20px; }
  .tl-item { flex-direction: column; gap: 4px; }
}