:root {
  color-scheme: dark light;
  --bg: #0b0d12;
  --bg-elev: #11141b;
  --bg-soft: #161a23;
  --fg: #e7eaf3;
  --fg-muted: #9aa3b2;
  --fg-dim: #6e7689;
  --accent: #7cc4ff;
  --accent-strong: #4aa3ff;
  --border: #1f2430;
  --border-strong: #2a3142;
  --code-bg: #0f1218;
  --code-fg: #d6dbe4;
  --success: #6fd28a;
  --warn: #f1c453;
  --danger: #ff7d8b;
  --maxw: 72rem;
  --radius: 10px;
  --radius-sm: 6px;
  --shadow: 0 1px 0 rgba(255, 255, 255, 0.02) inset, 0 12px 32px rgba(0, 0, 0, 0.35);
  --mono: ui-monospace, "JetBrains Mono", "SF Mono", Menlo, Consolas, monospace;
  --sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

@media (prefers-color-scheme: light) {
  :root {
    --bg: #f8fafc;
    --bg-elev: #ffffff;
    --bg-soft: #eef2f8;
    --fg: #1a1f2b;
    --fg-muted: #54607a;
    --fg-dim: #6b7790;
    --accent: #2563eb;
    --accent-strong: #1d4ed8;
    --border: #e2e8f0;
    --border-strong: #cbd5e1;
    --code-bg: #f1f5f9;
    --code-fg: #0f172a;
    --shadow: 0 1px 0 rgba(0, 0, 0, 0.02) inset, 0 8px 24px rgba(15, 23, 42, 0.06);
  }
}

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

html {
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  font-feature-settings: "ss01", "cv02";
  text-rendering: optimizeLegibility;
}

.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 1.25rem;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover,
a:focus-visible {
  color: var(--accent-strong);
  text-decoration: underline;
}

a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 3px;
}

.skip {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--bg-elev);
  color: var(--fg);
  padding: 0.5rem 1rem;
  z-index: 1000;
}
.skip:focus {
  left: 1rem;
  top: 1rem;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--border);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 0.85rem 1.25rem;
}
.brand {
  display: inline-flex;
  align-items: baseline;
  gap: 0.5rem;
  font-weight: 700;
  color: var(--fg);
}
.brand:hover {
  text-decoration: none;
}
.brand-mark {
  font-family: var(--mono);
  color: var(--accent);
  font-size: 1.15rem;
}
.brand-name {
  letter-spacing: -0.01em;
}

nav[aria-label="Primary"] {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  flex-wrap: wrap;
}
.nav-link {
  display: inline-flex;
  align-items: center;
  padding: 0.45rem 0.75rem;
  border-radius: var(--radius-sm);
  color: var(--fg-muted);
  font-size: 0.95rem;
}
.nav-link:hover,
.nav-link:focus-visible {
  background: var(--bg-soft);
  color: var(--fg);
  text-decoration: none;
}
.nav-link.active {
  color: var(--fg);
  background: var(--bg-soft);
}
.nav-external::after {
  content: " ↗";
  color: var(--fg-dim);
  font-size: 0.85em;
}

/* Hero */
.hero {
  padding: 5rem 0 3rem;
  border-bottom: 1px solid var(--border);
  background: radial-gradient(
      900px 360px at 20% -10%,
      color-mix(in srgb, var(--accent) 18%, transparent),
      transparent 70%
    ),
    radial-gradient(
      700px 280px at 90% 0%,
      color-mix(in srgb, var(--accent) 10%, transparent),
      transparent 70%
    );
}
.hero h1 {
  font-size: clamp(2rem, 5vw, 3.25rem);
  line-height: 1.1;
  margin: 0.4rem 0 0.85rem;
  letter-spacing: -0.02em;
}
.hero .lede {
  font-size: 1.15rem;
  color: var(--fg-muted);
  max-width: 42rem;
  margin: 0;
}
.eyebrow {
  margin: 0;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 0.78rem;
  color: var(--accent);
  font-weight: 600;
}

/* Sections */
.section {
  padding: 3rem 0;
  border-bottom: 1px solid var(--border);
}
.section:last-of-type {
  border-bottom: none;
}
.section h2 {
  font-size: clamp(1.4rem, 2.5vw, 1.85rem);
  letter-spacing: -0.015em;
  margin: 0 0 0.5rem;
}
.section .subhead {
  color: var(--fg-muted);
  margin: 0 0 1.5rem;
  max-width: 50rem;
}

/* CTAs */
.cta-row {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  margin-top: 1.5rem;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.65rem 1rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-strong);
  background: var(--bg-elev);
  color: var(--fg);
  font-weight: 500;
  font-size: 0.95rem;
}
.btn:hover {
  text-decoration: none;
  border-color: var(--accent);
  color: var(--fg);
}
.btn-primary {
  background: var(--accent);
  color: #0a1018;
  border-color: var(--accent);
}
@media (prefers-color-scheme: light) {
  .btn-primary {
    color: #ffffff;
  }
}
.btn-primary:hover {
  background: var(--accent-strong);
  border-color: var(--accent-strong);
}

/* Cards grid */
.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
  gap: 1rem;
  margin-top: 1.5rem;
}
.card {
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.1rem 1.15rem;
  box-shadow: var(--shadow);
}
.card h3 {
  font-size: 1.05rem;
  margin: 0 0 0.4rem;
  letter-spacing: -0.01em;
}
.card p {
  margin: 0;
  color: var(--fg-muted);
}
.card p + p {
  margin-top: 0.5rem;
}

/* Code */
.codeblock,
pre {
  background: var(--code-bg);
  color: var(--code-fg);
  font-family: var(--mono);
  font-size: 0.92rem;
  padding: 0.95rem 1.1rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow-x: auto;
  margin: 1rem 0;
  line-height: 1.55;
}
code {
  font-family: var(--mono);
  font-size: 0.92em;
  background: var(--bg-soft);
  color: var(--code-fg);
  padding: 0.1rem 0.35rem;
  border-radius: 4px;
}
pre code {
  padding: 0;
  background: transparent;
  border-radius: 0;
}

/* Callouts */
.callout {
  border-left: 3px solid var(--border-strong);
  background: var(--bg-soft);
  padding: 0.85rem 1rem;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  margin: 1rem 0;
  color: var(--fg-muted);
}
.callout p {
  margin: 0;
}
.callout p + p {
  margin-top: 0.5rem;
}
.callout-info {
  border-left-color: var(--accent);
}
.callout-warn {
  border-left-color: var(--warn);
}
.callout-success {
  border-left-color: var(--success);
}
.callout-danger {
  border-left-color: var(--danger);
}

/* Status badges */
.badge {
  display: inline-block;
  padding: 0.1rem 0.55rem;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  background: var(--bg-soft);
  color: var(--fg-muted);
  border: 1px solid var(--border);
  vertical-align: middle;
}
.badge-done {
  color: var(--success);
  border-color: color-mix(in srgb, var(--success) 35%, var(--border));
}
.badge-active {
  color: var(--accent);
  border-color: color-mix(in srgb, var(--accent) 35%, var(--border));
}
.badge-planned {
  color: var(--fg-dim);
}

/* Phase list */
.phase-list {
  list-style: none;
  padding: 0;
  margin: 1rem 0 0;
  display: grid;
  gap: 0.6rem;
}
.phase-list li {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.85rem;
  align-items: baseline;
  padding: 0.65rem 0.85rem;
  border: 1px solid var(--border);
  background: var(--bg-elev);
  border-radius: var(--radius-sm);
}
.phase-list strong {
  display: block;
  font-weight: 600;
}
.phase-list p {
  margin: 0.15rem 0 0;
  color: var(--fg-muted);
}

/* Definition lists */
.kv {
  display: grid;
  grid-template-columns: minmax(10rem, max-content) 1fr;
  column-gap: 1.25rem;
  row-gap: 0.5rem;
  margin: 1rem 0;
}
.kv dt {
  color: var(--fg-muted);
  font-family: var(--mono);
  font-size: 0.92rem;
}
.kv dd {
  margin: 0;
}

/* Text content */
.prose p,
.prose ul,
.prose ol {
  max-width: 50rem;
}
.prose ul,
.prose ol {
  padding-left: 1.2rem;
}
.prose li {
  margin: 0.3rem 0;
}
.prose h3 {
  margin: 2rem 0 0.5rem;
  letter-spacing: -0.01em;
}

/* Footer */
.site-footer {
  border-top: 1px solid var(--border);
  padding: 2rem 0 2.5rem;
  margin-top: 2rem;
  color: var(--fg-muted);
  font-size: 0.92rem;
}
.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 1rem;
}
.footer-tagline {
  margin: 0;
}
.footer-link {
  color: var(--fg-muted);
  margin-left: 1rem;
}
.footer-link:first-of-type {
  margin-left: 0;
}
.footer-link:hover {
  color: var(--fg);
}

@media (max-width: 640px) {
  .header-inner {
    flex-direction: column;
    align-items: flex-start;
    gap: 0.5rem;
    padding-bottom: 0.75rem;
  }
  .hero {
    padding: 3rem 0 2rem;
  }
  .footer-inner {
    flex-direction: column;
    align-items: flex-start;
  }
  .footer-link {
    margin-left: 0;
    margin-right: 1rem;
  }
}