/* iTrain landing — premium dark dev-tool aesthetic (Linear/Vercel-like). */
:root {
  --bg: #0a0a0b;
  --bg-elevated: #131316;
  --border: #1f1f23;
  --text: #f5f5f7;
  --muted: #8e8e93;
  --accent: #4f7cff;
  --accent-soft: rgba(79, 124, 255, 0.14);
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* ---------- Nav ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(10, 10, 11, 0.8);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
.nav-inner {
  max-width: 1080px;
  margin: 0 auto;
  padding: 16px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand-mark {
  width: 30px; height: 30px;
  display: grid; place-items: center;
  background: var(--accent-soft);
  color: var(--accent);
  border: 1px solid rgba(79, 124, 255, 0.35);
  border-radius: 8px;
  font-weight: 800;
  font-size: 13px;
  letter-spacing: 0.5px;
}
.brand-name { font-weight: 700; letter-spacing: -0.2px; }
.nav-links { display: flex; gap: 28px; }
.nav-links a {
  color: var(--muted);
  text-decoration: none;
  font-size: 14px;
  font-weight: 500;
  transition: color 0.15s ease;
}
.nav-links a:hover { color: var(--text); }

/* ---------- Hero ---------- */
.hero {
  border-bottom: 1px solid var(--border);
  background:
    radial-gradient(ellipse 60% 50% at 50% -10%, rgba(79, 124, 255, 0.12), transparent),
    var(--bg);
}
.hero-inner {
  max-width: 1080px;
  margin: 0 auto;
  padding: 120px 24px 96px;
  text-align: center;
}
.eyebrow {
  display: inline-block;
  color: var(--accent);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0.6px;
  text-transform: uppercase;
  padding: 6px 14px;
  border: 1px solid rgba(79, 124, 255, 0.35);
  border-radius: 999px;
  background: var(--accent-soft);
  margin-bottom: 28px;
}
h1 {
  font-size: clamp(40px, 6vw, 64px);
  font-weight: 800;
  letter-spacing: -2px;
  line-height: 1.08;
  margin-bottom: 24px;
}
.gradient {
  background: linear-gradient(120deg, #4f7cff 0%, #64d2ff 50%, #bf5af2 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-sub {
  max-width: 560px;
  margin: 0 auto 36px;
  color: var(--muted);
  font-size: 18px;
}

/* ---------- CTA (one primary action) ---------- */
.cta {
  display: inline-block;
  padding: 14px 32px;
  background: var(--accent);
  color: #fff;
  font-size: 16px;
  font-weight: 600;
  text-decoration: none;
  border-radius: 10px;
  box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.06) inset, 0 8px 24px rgba(79, 124, 255, 0.35);
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.cta:hover { transform: translateY(-1px); box-shadow: 0 0 0 1px rgba(255, 255, 255, 0.06) inset, 0 12px 32px rgba(79, 124, 255, 0.45); }
.cta-note { margin-top: 14px; font-size: 13px; color: var(--muted); }

/* Secondary action (not the primary CTA — exactly one .cta per page). */
.cta-secondary {
  display: inline-block;
  padding: 12px 28px;
  color: var(--accent);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  border: 1px solid rgba(79, 124, 255, 0.4);
  border-radius: 10px;
  background: var(--accent-soft);
  transition: background 0.15s ease;
}
.cta-secondary:hover { background: rgba(79, 124, 255, 0.22); }

/* ---------- Sections ---------- */
.section { padding: 96px 24px; }
.section.alt { background: var(--bg-elevated); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.section-inner { max-width: 1080px; margin: 0 auto; }
h2 {
  font-size: 34px;
  font-weight: 800;
  letter-spacing: -1px;
  margin-bottom: 48px;
  text-align: center;
}

.grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 20px; }
.card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px 28px;
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.card:hover { border-color: rgba(79, 124, 255, 0.4); transform: translateY(-2px); }
.card-icon { font-size: 26px; margin-bottom: 16px; }
.card h3 { font-size: 18px; font-weight: 700; margin-bottom: 8px; letter-spacing: -0.2px; }
.card p { color: var(--muted); font-size: 15px; }

.steps { list-style: none; max-width: 640px; margin: 0 auto; display: grid; gap: 28px; }
.steps li { display: flex; gap: 20px; align-items: flex-start; }
.step-num {
  font-size: 14px;
  font-weight: 700;
  color: var(--accent);
  background: var(--accent-soft);
  border: 1px solid rgba(79, 124, 255, 0.3);
  padding: 4px 10px;
  border-radius: 8px;
  flex-shrink: 0;
}
.steps strong { display: block; margin-bottom: 2px; }
.steps div { color: var(--muted); font-size: 15px; }

.pilot-box {
  text-align: center;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: 20px;
  padding: 56px 32px;
}
.pilot-box h2 { margin-bottom: 12px; }
.pilot-box p { color: var(--muted); margin-bottom: 28px; }

/* ---------- Footer ---------- */
.footer { border-top: 1px solid var(--border); padding: 28px 24px; }
.footer-inner {
  max-width: 1080px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  color: var(--muted);
  font-size: 13px;
}

@media (max-width: 640px) {
  .nav-links { display: none; }
  .hero-inner { padding: 80px 20px 64px; }
  .section { padding: 64px 20px; }
}