/* ============================================
   KRYBON LAB — Design System
   Corporate trust, structured, navy/blue
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Source+Serif+4:opsz,wght@8..60,400;8..60,500;8..60,600;8..60,700&family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap');

:root {
  /* Color */
  --ink: #0A1628;
  --navy: #0B1E3D;
  --steel: #2E5E8C;
  --signal: #3B7DD8;
  --signal-dim: #2E5E8C;
  --bg: #F7F8FA;
  --bg-alt: #EEF1F6;
  --paper: #FFFFFF;
  --slate: #6B7280;
  --slate-light: #9CA3AF;
  --line: #DCE2EA;
  --line-dark: #1C2D4D;
  --good: #1A7A4C;

  /* Type */
  --serif: 'Source Serif 4', Georgia, serif;
  --sans: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  --mono: 'JetBrains Mono', 'SF Mono', monospace;

  /* Layout */
  --maxw: 1180px;
  --pad: clamp(20px, 5vw, 64px);
  --radius: 3px;
}

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

html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
}

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

h1, h2, h3, h4 {
  font-family: var(--serif);
  font-weight: 600;
  line-height: 1.15;
  letter-spacing: -0.01em;
  color: var(--navy);
}

h1 { font-size: clamp(2.4rem, 5vw, 3.8rem); }
h2 { font-size: clamp(1.8rem, 3.5vw, 2.6rem); }
h3 { font-size: clamp(1.3rem, 2.2vw, 1.6rem); }
h4 { font-size: 1.1rem; }

p { color: var(--slate); }

.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 var(--pad);
}

.mono-label {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--steel);
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.mono-label::before {
  content: '';
  width: 16px;
  height: 1px;
  background: var(--signal);
  display: inline-block;
}

/* ---------- Header / Nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(247, 248, 250, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px var(--pad);
  max-width: var(--maxw);
  margin: 0 auto;
}

.logo {
  font-family: var(--serif);
  font-weight: 600;
  font-size: 1.25rem;
  color: var(--navy);
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-mark {
  width: 28px;
  height: 28px;
  position: relative;
  flex-shrink: 0;
}

.nav-links {
  display: flex;
  gap: 32px;
  align-items: center;
}

.nav-links a {
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--ink);
  position: relative;
  padding: 6px 0;
  transition: color 0.2s ease;
}

.nav-links a:hover,
.nav-links a:focus-visible {
  color: var(--signal);
}

.nav-links a.active {
  color: var(--signal);
}

.nav-links a.active::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: var(--signal);
}

.nav-cta {
  background: var(--navy);
  color: #fff !important;
  padding: 10px 22px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.88rem;
  transition: background 0.2s ease;
}

.nav-cta:hover { background: var(--signal); }

.nav-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--navy);
  margin: 5px 0;
  transition: 0.25s ease;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 26px;
  border-radius: var(--radius);
  font-weight: 600;
  font-size: 0.92rem;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s ease;
}

.btn-primary {
  background: var(--navy);
  color: #fff;
}
.btn-primary:hover { background: var(--signal); transform: translateY(-1px); }

.btn-outline {
  background: transparent;
  border: 1px solid var(--line-dark);
  color: var(--navy);
}
.btn-outline:hover { border-color: var(--signal); color: var(--signal); }

.btn-light {
  background: #fff;
  color: var(--navy);
}
.btn-light:hover { background: var(--bg-alt); }

/* ---------- Sections ---------- */
section { padding: 96px 0; }
section.tight { padding: 64px 0; }

.section-head {
  max-width: 640px;
  margin-bottom: 56px;
}

.section-head h2 { margin-top: 14px; }
.section-head p { margin-top: 16px; font-size: 1.05rem; }

/* ---------- Footer ---------- */
.site-footer {
  background: var(--ink);
  color: var(--bg-alt);
  padding: 72px 0 28px;
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1.2fr;
  gap: 40px;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255,255,255,0.1);
}

.footer-grid h4 {
  color: #fff;
  font-family: var(--sans);
  font-size: 0.82rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-weight: 600;
  margin-bottom: 18px;
}

.footer-grid a {
  display: block;
  color: #B8C2D6;
  font-size: 0.9rem;
  margin-bottom: 12px;
  transition: color 0.2s ease;
}

.footer-grid a:hover { color: var(--signal); }

.footer-grid p { color: #8694AD; font-size: 0.88rem; }

.footer-logo {
  font-family: var(--serif);
  font-size: 1.3rem;
  color: #fff;
  margin-bottom: 14px;
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 28px;
  font-size: 0.82rem;
  color: #6B7A94;
}

.footer-bottom a { color: #6B7A94; }
.footer-bottom a:hover { color: var(--signal); }

/* ---------- Utility ---------- */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 48px; }
.grid-3 { display: grid; grid-template-columns: repeat(3, 1fr); gap: 32px; }
.grid-4 { display: grid; grid-template-columns: repeat(4, 1fr); gap: 28px; }

.card {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 32px;
}

.divider {
  height: 1px;
  background: var(--line);
  border: none;
  margin: 0;
}

.eyebrow {
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--signal);
  font-weight: 500;
}

/* ---------- Page hero (inner pages) ---------- */
.page-hero {
  background: var(--navy);
  color: #fff;
  padding: 72px 0 64px;
  position: relative;
  overflow: hidden;
}

.page-hero .eyebrow { color: #8FB8E8; }
.page-hero h1 { color: #fff; margin-top: 14px; }
.page-hero p { color: #C2D1E8; max-width: 640px; margin-top: 18px; font-size: 1.08rem; }

/* ---------- Stats row ---------- */
.stats-row {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  background: var(--paper);
}

.stat-item {
  padding: 28px 24px;
  border-right: 1px solid var(--line);
}
.stat-item:last-child { border-right: none; }

.stat-num {
  font-family: var(--mono);
  font-size: 2rem;
  font-weight: 600;
  color: var(--navy);
  display: block;
}

.stat-label {
  font-size: 0.82rem;
  color: var(--slate);
  margin-top: 4px;
}

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .nav-links { display: none; }
  .nav-toggle { display: block; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .stats-row { grid-template-columns: 1fr 1fr; }
  .stat-item { border-bottom: 1px solid var(--line); }
  .footer-grid { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 560px) {
  .stats-row { grid-template-columns: 1fr; }
  .footer-grid { grid-template-columns: 1fr; }
  .footer-bottom { flex-direction: column; gap: 12px; align-items: flex-start; }
}

/* ---------- Mobile nav drawer ---------- */
.mobile-nav {
  display: none;
  position: fixed;
  inset: 0;
  background: var(--navy);
  z-index: 200;
  flex-direction: column;
  padding: 24px var(--pad);
}

.mobile-nav.open { display: flex; }

.mobile-nav-top {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 48px;
}

.mobile-nav a {
  color: #fff;
  font-family: var(--serif);
  font-size: 1.8rem;
  padding: 16px 0;
  border-bottom: 1px solid rgba(255,255,255,0.12);
}

.mobile-nav .nav-cta {
  margin-top: 24px;
  text-align: center;
  justify-content: center;
}

.mobile-nav-close {
  background: none;
  border: none;
  color: #fff;
  font-size: 1.8rem;
  cursor: pointer;
}

/* Focus visibility for accessibility */
a:focus-visible, button:focus-visible, input:focus-visible, textarea:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 2px;
}