/* ══════════════════════════════════════════════════════════
   Rabbit Design System
   Light theme. Minimal. Research-grade.
   ══════════════════════════════════════════════════════════ */

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

:root {
  --bg: #ffffff;
  --bg-soft: #fafafa;
  --bg-muted: #f4f4f5;
  --bg-dark: #09090b;
  --text: #09090b;
  --text-2: #3f3f46;
  --text-3: #71717a;
  --text-4: #a1a1aa;
  --text-5: #d4d4d8;
  --violet: #7c3aed;
  --violet-light: #ede9fe;
  --violet-soft: #f5f3ff;
  --violet-dark: #5b21b6;
  --teal: #0d9488;
  --teal-light: #ccfbf1;
  --green: #059669;
  --amber: #d97706;
  --rose: #e11d48;
  --border: #e4e4e7;
  --border-light: #f4f4f5;
  --radius: 12px;
  --radius-lg: 20px;
  --radius-sm: 8px;
  --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
  --shadow: 0 1px 3px rgba(0,0,0,0.06), 0 1px 2px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.06);
  --shadow-lg: 0 10px 40px rgba(0,0,0,0.08);
}

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

::selection { background: var(--violet-light); color: var(--violet-dark); }

a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }

/* ── Container ─────────────────────────────── */
.container { max-width: 1200px; margin: 0 auto; padding: 0 2rem; }
.container-narrow { max-width: 800px; margin: 0 auto; padding: 0 2rem; }
.container-wide { max-width: 1400px; margin: 0 auto; padding: 0 2rem; }

section { padding: 6rem 0; }

/* ── Typography ────────────────────────────── */
.t-display {
  font-size: clamp(2.5rem, 5.5vw, 4rem);
  font-weight: 800;
  letter-spacing: -0.035em;
  line-height: 1.08;
  color: var(--text);
}

.t-h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  font-weight: 800;
  letter-spacing: -0.03em;
  line-height: 1.12;
}

.t-h2 {
  font-size: clamp(1.5rem, 3vw, 2.2rem);
  font-weight: 700;
  letter-spacing: -0.025em;
  line-height: 1.2;
}

.t-h3 {
  font-size: 1.1rem;
  font-weight: 700;
  letter-spacing: -0.01em;
  line-height: 1.3;
}

.t-body { font-size: 1.05rem; color: var(--text-2); line-height: 1.7; }
.t-body-sm { font-size: 0.92rem; color: var(--text-3); line-height: 1.65; }
.t-caption { font-size: 0.78rem; color: var(--text-4); line-height: 1.5; }

.t-label {
  font-size: 0.7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--violet);
}

.t-mono {
  font-family: 'JetBrains Mono', 'SF Mono', 'Fira Code', monospace;
}

.max-w-lg { max-width: 640px; }
.max-w-md { max-width: 480px; }
.mx-auto { margin-left: auto; margin-right: auto; }
.text-center { text-align: center; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.mt-4 { margin-top: 2rem; }
.mt-6 { margin-top: 3rem; }
.mt-8 { margin-top: 4rem; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mb-4 { margin-bottom: 2rem; }

/* ── Buttons ───────────────────────────────── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.6rem 1.25rem;
  border-radius: var(--radius-sm);
  font-size: 0.85rem;
  font-weight: 600;
  font-family: inherit;
  text-decoration: none;
  cursor: pointer;
  transition: all 0.2s;
  border: none;
  line-height: 1.4;
}

.btn-dark {
  background: var(--bg-dark);
  color: white;
}
.btn-dark:hover { background: #1a1a1f; transform: translateY(-1px); box-shadow: var(--shadow-md); }

.btn-violet {
  background: var(--violet);
  color: white;
}
.btn-violet:hover { background: var(--violet-dark); transform: translateY(-1px); }

.btn-outline {
  background: transparent;
  color: var(--text);
  border: 1px solid var(--border);
}
.btn-outline:hover { border-color: var(--text-4); background: var(--bg-soft); }

.btn-ghost { background: transparent; color: var(--text-3); padding: 0.5rem 0.75rem; }
.btn-ghost:hover { color: var(--text); }

.btn-lg { padding: 0.75rem 1.75rem; font-size: 0.95rem; border-radius: var(--radius); }

.btn svg { width: 16px; height: 16px; }

/* ── Nav ───────────────────────────────────── */
nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  height: 60px;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: rgba(255,255,255,0.85);
  backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--border-light);
}

.nav-left { display: flex; align-items: center; gap: 2.5rem; }

.nav-logo {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  text-decoration: none;
}

.nav-logo svg { width: 22px; height: 22px; color: var(--text); }

.nav-logo .wordmark {
  font-size: 1.05rem;
  font-weight: 800;
  letter-spacing: -0.03em;
  color: var(--text);
}

.nav-logo .wordmark-light { color: var(--text-4); }

.nav-menu { display: flex; gap: 0.15rem; }

.nav-menu a {
  font-size: 0.82rem;
  font-weight: 500;
  color: var(--text-3);
  padding: 0.35rem 0.65rem;
  border-radius: 6px;
  transition: all 0.15s;
}
.nav-menu a:hover { color: var(--text); background: var(--bg-muted); }
.nav-menu a.active { color: var(--text); font-weight: 600; }

.nav-right { display: flex; align-items: center; gap: 0.5rem; }

/* ── Cards ─────────────────────────────────── */
.card {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
  transition: all 0.3s;
}
.card:hover { border-color: var(--text-5); box-shadow: var(--shadow-md); }

.card-flat {
  background: var(--bg-soft);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: 1.75rem;
}

/* ── Divider ───────────────────────────────── */
.divider { height: 1px; background: var(--border); margin: 0; }

/* ── Pill / Badge ──────────────────────────── */
.pill {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.25rem 0.75rem;
  border-radius: 100px;
  font-size: 0.72rem;
  font-weight: 600;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text-3);
}

.pill-violet { background: var(--violet-soft); color: var(--violet); border-color: transparent; }

/* ── Reveal ────────────────────────────────── */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}
.reveal.visible { opacity: 1; transform: translateY(0); }
.reveal-d1 { transition-delay: 0.1s; }
.reveal-d2 { transition-delay: 0.2s; }
.reveal-d3 { transition-delay: 0.3s; }
.reveal-d4 { transition-delay: 0.4s; }

/* ── Footer ────────────────────────────────── */
footer {
  background: var(--bg-dark);
  color: white;
  padding: 4rem 0 2rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr 1fr;
  gap: 3rem;
  margin-bottom: 3rem;
}

.footer-brand p { color: #a1a1aa; font-size: 0.85rem; line-height: 1.6; margin-top: 0.75rem; }

.footer-col h4 {
  font-size: 0.72rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: #71717a;
  margin-bottom: 0.75rem;
}

.footer-col a {
  display: block;
  font-size: 0.85rem;
  color: #a1a1aa;
  padding: 0.25rem 0;
  transition: color 0.15s;
}
.footer-col a:hover { color: white; }

.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.08);
  padding-top: 1.5rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.footer-bottom p { font-size: 0.72rem; color: #52525b; }
.footer-bottom a { font-size: 0.72rem; color: #52525b; }
.footer-bottom a:hover { color: #a1a1aa; }

.footer-legal { display: flex; gap: 1.5rem; }

/* ── Responsive ────────────────────────────── */
@media (max-width: 900px) {
  .nav-menu { display: none; }
  .footer-grid { grid-template-columns: 1fr 1fr; gap: 2rem; }
  .hero-split { grid-template-columns: 1fr !important; }
  .hero-visual { display: none; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr !important; }
  .footer-bottom { flex-direction: column; gap: 0.75rem; text-align: center; }
}

/* ── Grid helpers ──────────────────────────── */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 1.5rem; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1.5rem; }
.gap-2 { gap: 2rem; }
.gap-3 { gap: 3rem; }
.gap-4 { gap: 4rem; }

/* ── Code blocks ───────────────────────────── */
.code-block {
  background: var(--bg-dark);
  border-radius: var(--radius);
  overflow: hidden;
}

.code-block pre {
  padding: 1.25rem;
  font-family: 'JetBrains Mono', monospace;
  font-size: 0.78rem;
  line-height: 1.7;
  color: #a1a1aa;
  overflow-x: auto;
}

.code-block .k { color: #a78bfa; }
.code-block .s { color: #6ee7b7; }
.code-block .n { color: #fca5a5; }
.code-block .c { color: #52525b; }
</style>