:root {
  --color-bg: #ffffff;
  --color-bg-subtle: #f7f8fa;
  --color-text: #14181f;
  --color-text-muted: #545b68;
  --color-border: #e2e5ea;
  --color-primary: #1f4fd8;
  --color-primary-ink: #ffffff;
  --color-primary-hover: #1a3fb0;
  --color-accent: #0a8a5f;
  --color-danger: #b3261e;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Inter, Roboto, Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
  --radius: 8px;
  --container-w: 1120px;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --color-bg: #0f1216;
    --color-bg-subtle: #171b21;
    --color-text: #eef1f5;
    --color-text-muted: #9aa3b2;
    --color-border: #2a2f38;
    --color-primary: #6f93ff;
    --color-primary-ink: #0f1216;
    --color-primary-hover: #8fabff;
    --color-accent: #35c98d;
    --color-danger: #ff6b61;
  }
}

:root[data-theme="dark"] {
  --color-bg: #0f1216;
  --color-bg-subtle: #171b21;
  --color-text: #eef1f5;
  --color-text-muted: #9aa3b2;
  --color-border: #2a2f38;
  --color-primary: #6f93ff;
  --color-primary-ink: #0f1216;
  --color-primary-hover: #8fabff;
  --color-accent: #35c98d;
  --color-danger: #ff6b61;
}

* { box-sizing: border-box; }
html { color-scheme: light dark; }
body {
  margin: 0;
  background: var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: var(--color-primary); }
code, pre { font-family: var(--font-mono); }
pre {
  background: var(--color-bg-subtle);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 16px;
  overflow-x: auto;
}

.container {
  max-width: var(--container-w);
  margin: 0 auto;
  padding: 0 20px;
}

/* Header */
.site-header {
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  background: var(--color-bg);
  z-index: 10;
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: 16px;
  gap: 24px;
  flex-wrap: wrap;
}
.brand {
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--color-text);
  text-decoration: none;
}
.nav {
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
  align-items: center;
}
.nav a {
  color: var(--color-text-muted);
  text-decoration: none;
  font-size: 0.95rem;
}
.nav a:hover, .nav a[aria-current="page"] { color: var(--color-text); }
.nav-cta {
  display: flex;
  gap: 12px;
  align-items: center;
}

/* Buttons */
.btn {
  display: inline-block;
  border-radius: var(--radius);
  padding: 10px 18px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  border: 1px solid transparent;
}
.btn-primary {
  background: var(--color-primary);
  color: var(--color-primary-ink);
}
.btn-primary:hover { background: var(--color-primary-hover); }
.btn-secondary {
  background: transparent;
  color: var(--color-text);
  border-color: var(--color-border);
}
.btn-secondary:hover { border-color: var(--color-text-muted); }

/* Hero / sections */
.hero {
  padding-block: 72px;
  border-bottom: 1px solid var(--color-border);
}
.hero h1 {
  font-size: clamp(2rem, 4vw, 3rem);
  line-height: 1.1;
  margin: 0 0 20px;
  max-width: 18ch;
}
.hero p.lede {
  font-size: 1.15rem;
  color: var(--color-text-muted);
  max-width: 60ch;
  margin: 0 0 32px;
}
.hero-actions { display: flex; gap: 12px; flex-wrap: wrap; }

section { padding-block: 56px; }
section.subtle { background: var(--color-bg-subtle); }
h2 { font-size: 1.75rem; margin-top: 0; }
h3 { font-size: 1.2rem; }
.eyebrow {
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-size: 0.75rem;
  font-weight: 700;
  color: var(--color-primary);
  margin: 0 0 8px;
}

.grid {
  display: grid;
  gap: 24px;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}
.card {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 24px;
}
.card h3 { margin-top: 0; }

.stat-row {
  display: grid;
  gap: 24px;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  margin-block: 32px;
}
.stat .num {
  font-size: 2rem;
  font-weight: 700;
  color: var(--color-primary);
}
.stat .label {
  color: var(--color-text-muted);
  font-size: 0.9rem;
}

table { width: 100%; border-collapse: collapse; }
th, td {
  text-align: left;
  padding: 12px 16px;
  border-bottom: 1px solid var(--color-border);
}
th { color: var(--color-text-muted); font-weight: 600; font-size: 0.9rem; }

.callout {
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-primary);
  border-radius: var(--radius);
  padding: 16px 20px;
  background: var(--color-bg-subtle);
}
.callout.warn { border-left-color: var(--color-danger); }

.breadcrumbs {
  font-size: 0.85rem;
  color: var(--color-text-muted);
  margin-bottom: 16px;
}
.breadcrumbs a { color: var(--color-text-muted); }

/* Footer */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding-block: 40px;
  color: var(--color-text-muted);
  font-size: 0.9rem;
}
.site-footer .container {
  display: grid;
  gap: 32px;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
}
.site-footer h4 {
  color: var(--color-text);
  font-size: 0.85rem;
  margin: 0 0 12px;
}
.site-footer ul { list-style: none; padding: 0; margin: 0; display: grid; gap: 8px; }
.site-footer a { color: var(--color-text-muted); text-decoration: none; }
.site-footer a:hover { color: var(--color-text); }
.footer-bottom {
  margin-top: 32px;
  padding-top: 24px;
  border-top: 1px solid var(--color-border);
  font-size: 0.8rem;
}

/* Utility */
.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}
.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--color-primary);
  color: var(--color-primary-ink);
  padding: 10px 16px;
  z-index: 100;
}
.skip-link:focus { left: 8px; top: 8px; }

@media (max-width: 640px) {
  .hero { padding-block: 48px; }
  section { padding-block: 40px; }
}