/* ProofWindow — editorial evidence-lab aesthetic
   Deep ink #0B1220 · proof-amber #E8A838 · system-ui + ui-monospace (no webfonts) */
:root {
  --ink: #0B1220;
  --ink-elev: #121A2B;
  --ink-line: #1E2A3F;
  --ink-muted: #2A3A55;
  --fog: #C5D0E0;
  --paper: #E8EDF5;
  --paper-dim: #D8E0EC;
  --amber: #E8A838;
  --amber-dim: #B87E1E;
  --amber-glow: rgba(232, 168, 56, 0.14);
  --ok: #3DCF8E;
  --warn: #E8A838;
  --danger: #E85D5D;
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "Cascadia Code", "SF Mono", Menlo, Consolas, monospace;
  --max: 72rem;
  --prose: 42rem;
  --radius: 10px;
  --shadow: 0 1px 0 rgba(255,255,255,0.04), 0 12px 40px rgba(0,0,0,0.35);
  --focus: 0 0 0 2px var(--ink), 0 0 0 4px var(--amber);
}

*, *::before, *::after { box-sizing: border-box; }
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 {
  margin: 0;
  min-height: 100vh;
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--paper);
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(232,168,56,0.08), transparent 55%),
    radial-gradient(900px 500px at 100% 0%, rgba(61,207,142,0.05), transparent 50%),
    linear-gradient(180deg, #0D1524 0%, var(--ink) 40%, #080E18 100%);
}

img, svg { max-width: 100%; height: auto; display: block; }
a { color: var(--amber); text-decoration-thickness: 1px; text-underline-offset: 0.18em; }
a:hover { color: #F0C06A; }

/* Visible focus for keyboard users on interactive controls */
a:focus-visible,
button:focus-visible,
.btn:focus-visible,
.nav-toggle:focus-visible,
summary:focus-visible,
.card:focus-visible,
.chip:focus-visible,
input:focus-visible,
select:focus-visible,
textarea:focus-visible {
  outline: none;
  box-shadow: var(--focus);
  border-radius: 4px;
}

/* Skip target: allow programmatic focus without a page-wide ring */
#main:focus {
  outline: none;
}

.skip-link {
  position: absolute;
  left: 1rem;
  top: -100px;
  z-index: 1000;
  padding: 0.65rem 1rem;
  background: var(--amber);
  color: var(--ink);
  font-weight: 600;
  border-radius: 6px;
  text-decoration: none;
}
.skip-link:focus,
.skip-link:focus-visible {
  top: 1rem;
  outline: none;
  box-shadow: var(--focus);
}

.wrap {
  width: min(100% - 2rem, var(--max));
  margin-inline: auto;
}

/* Launch banner */
.launch-banner {
  background: var(--ink-elev);
  border-bottom: 1px solid var(--ink-line);
  color: var(--paper);
  font-size: 0.875rem;
  text-align: center;
  padding: 0.55rem 1rem;
}
.launch-banner strong { color: var(--paper); font-weight: 600; }

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(11, 18, 32, 0.96);
  border-bottom: 1px solid var(--ink-line);
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.85rem 0;
}
.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  color: var(--paper);
  font-weight: 700;
  letter-spacing: -0.02em;
}
.brand-mark {
  display: inline-flex;
  width: 2rem;
  height: 2rem;
  flex-shrink: 0;
  border-radius: 7px;
  overflow: hidden;
  box-shadow: 0 0 0 1px rgba(232,168,56,0.3);
}
.brand-mark svg {
  width: 100%;
  height: 100%;
  display: block;
}
.error-page > .brand-mark {
  margin: 0 auto 1rem;
  width: 3rem;
  height: 3rem;
}
.brand-text { font-size: 1.05rem; }
.brand-text span { color: var(--amber); }

.nav-toggle {
  display: none;
  background: var(--ink-elev);
  border: 1px solid var(--ink-line);
  color: var(--paper);
  border-radius: 8px;
  padding: 0.45rem 0.7rem;
  font: inherit;
  cursor: pointer;
}
.site-nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 0.25rem 1.15rem;
  flex-wrap: wrap;
  align-items: center;
}
.site-nav a {
  color: var(--fog);
  text-decoration: none;
  font-size: 0.92rem;
  font-weight: 500;
}
.site-nav a:hover, .site-nav a[aria-current="page"] { color: var(--paper); }
.site-nav a[aria-current="page"] {
  box-shadow: inset 0 -2px 0 var(--amber);
}

@media (max-width: 820px) {
  .nav-toggle { display: inline-flex; align-items: center; gap: 0.35rem; min-height: 44px; }
  .site-nav {
    display: none;
    width: 100%;
    padding-bottom: 0.85rem;
    max-height: min(70vh, 24rem);
    overflow-y: auto;
  }
  .site-nav.is-open { display: block; }
  .header-inner { flex-wrap: wrap; }
  .site-nav ul { flex-direction: column; align-items: flex-start; gap: 0.65rem; }
  .hero-grid { display: flex; flex-direction: column; }
  .hero-lab { order: -1; }
  .btn-row .btn, .btn { min-height: 44px; width: 100%; justify-content: center; }
  .btn-row { flex-direction: column; }
  .card-grid {
    grid-template-columns: repeat(auto-fill, minmax(min(100%, 16.5rem), 1fr));
  }
}

/* Main */
main { padding: 2.25rem 0 4rem; }
.hero {
  display: grid;
  gap: 1.75rem;
  padding: 1.5rem 0 2.5rem;
  border-bottom: 1px solid var(--ink-line);
  margin-bottom: 2.5rem;
}
.hero-grid {
  display: grid;
  gap: 2rem;
  align-items: start;
}
@media (min-width: 900px) {
  .hero-grid { grid-template-columns: 1.35fr 0.9fr; }
}
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  font-family: var(--font-mono);
  font-size: 0.75rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--amber);
  margin: 0 0 0.85rem;
}
.eyebrow::before {
  content: "";
  width: 0.55rem;
  height: 0.55rem;
  border-radius: 2px;
  background: var(--amber);
  box-shadow: 0 0 12px var(--amber);
}
h1 {
  font-size: clamp(1.85rem, 3.5vw, 2.75rem);
  line-height: 1.15;
  letter-spacing: -0.03em;
  margin: 0 0 1rem;
  font-weight: 700;
  color: #F4F7FC;
}
h2 {
  font-size: clamp(1.35rem, 2.2vw, 1.65rem);
  letter-spacing: -0.02em;
  margin: 2.5rem 0 0.85rem;
  color: #F0F4FA;
}
h3 {
  font-size: 1.12rem;
  margin: 1.75rem 0 0.55rem;
  color: var(--paper);
}
.lede, .answer-block {
  font-size: 1.125rem;
  color: var(--paper-dim);
  max-width: var(--prose);
  margin: 0 0 1.25rem;
}
.answer-block {
  background: var(--amber-glow);
  border: 1px solid rgba(232,168,56,0.28);
  border-left: 3px solid var(--amber);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 1rem 1.15rem;
  color: var(--paper);
  box-shadow: inset 4px 0 0 0 rgba(232,168,56,0.35);
}
.answer-block strong { color: var(--amber); }

.meta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.65rem 1.25rem;
  font-size: 0.875rem;
  color: var(--fog);
  margin: 1rem 0 0;
}
.meta-row a { color: var(--paper-dim); }
.ev-id {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--amber);
  background: rgba(232,168,56,0.1);
  border: 1px solid rgba(232,168,56,0.25);
  padding: 0.15rem 0.45rem;
  border-radius: 4px;
}

/* Panels & cards */
.panel {
  background: var(--ink-elev);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius);
  padding: 1.25rem 1.35rem;
  box-shadow: var(--shadow);
}
.panel-lab {
  background:
    linear-gradient(180deg, rgba(232,168,56,0.04), transparent 40%),
    var(--ink-elev);
  border-color: rgba(232,168,56,0.22);
}
.panel h2, .panel h3 { margin-top: 0; }
.stat-grid {
  display: grid;
  gap: 0.85rem;
  grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr));
}
.stat {
  padding: 0.85rem;
  background: rgba(0,0,0,0.22);
  border-radius: 8px;
  border: 1px solid var(--ink-line);
}
.stat .n {
  font-family: var(--font-mono);
  font-size: 1.35rem;
  color: var(--amber);
  font-weight: 600;
}
.stat .l { font-size: 0.8rem; color: var(--fog); margin-top: 0.2rem; }

.card-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fill, minmax(min(100%, 16.5rem), 1fr));
  margin: 1.25rem 0 2rem;
}
.card {
  display: flex;
  flex-direction: column;
  gap: 0.55rem;
  padding: 1.15rem 1.2rem;
  background: var(--ink-elev);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius);
  text-decoration: none;
  color: inherit;
  transition: border-color 0.15s ease, transform 0.15s ease;
}
.card:hover {
  border-color: var(--amber);
  transform: translateY(-2px);
  color: inherit;
}
.card:focus-visible {
  border-color: var(--amber);
  outline: none;
  box-shadow: var(--focus);
}
@media (prefers-reduced-motion: reduce) {
  .card { transition: border-color 0.15s ease; }
  .card:hover { transform: none; }
}
.card-head {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0.45rem 0.75rem;
}
.card .card-id {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--amber);
  letter-spacing: 0.04em;
  flex-shrink: 0;
}
.card h3 {
  margin: 0;
  font-size: 1.05rem;
  color: #F2F6FC;
}
.card p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--fog);
  flex: 1;
}
.card .card-cta {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--amber);
  margin-top: 0.35rem;
}

/* Experience callout */
.experienceNote,
.experience-callout {
  display: grid;
  gap: 0.5rem;
  margin: 1.5rem 0;
  padding: 1rem 1.15rem;
  border-radius: var(--radius);
  border: 1px dashed rgba(61,207,142,0.35);
  background: rgba(61,207,142,0.06);
}
.experienceNote .label,
.experience-callout .label {
  font-family: var(--font-mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--ok);
}
.experienceNote p,
.experience-callout p { margin: 0; color: var(--paper-dim); font-size: 0.98rem; }

/* TOC */
details.toc {
  margin: 1rem 0 1.5rem;
  padding: 0.85rem 1rem;
  background: var(--ink-elev);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius);
}
details.toc > summary {
  cursor: pointer;
  font-family: var(--font-mono);
  font-size: 0.95rem;
  color: var(--fog);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  list-style: none;
}
details.toc > summary::-webkit-details-marker { display: none; }
details.toc nav { margin-top: 0.65rem; }
.toc {
  margin: 1.5rem 0 2rem;
  padding: 1rem 1.2rem;
  background: rgba(0,0,0,0.2);
  border: 1px solid var(--ink-line);
  border-radius: var(--radius);
  max-width: var(--prose);
}
.toc h2 { margin: 0 0 0.65rem; font-size: 0.95rem; color: var(--fog); text-transform: uppercase; letter-spacing: 0.05em; }
.toc ol { margin: 0; padding-left: 1.2rem; }
.toc a { color: var(--paper-dim); text-decoration: none; }
.toc a:hover { color: var(--amber); }

/* Breadcrumb */
.breadcrumb {
  font-size: 0.85rem;
  color: var(--fog);
  margin: 0 0 1.25rem;
}
.breadcrumb ol {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}
.breadcrumb li:not(:last-child)::after {
  content: "/";
  margin-left: 0.35rem;
  color: var(--ink-muted);
  speak: never;
}
.breadcrumb a { color: var(--fog); text-decoration: none; }
.breadcrumb a:hover { color: var(--amber); }
.breadcrumb [aria-current="page"] { color: var(--paper-dim); }

/* Prose */
.prose { max-width: var(--prose); }
.prose p { margin: 0 0 1rem; color: var(--paper-dim); }
.prose ul, .prose ol { color: var(--paper-dim); padding-left: 1.25rem; margin: 0 0 1.15rem; }
.prose li { margin-bottom: 0.4rem; }
.prose strong { color: var(--paper); }
.prose code, .mono {
  font-family: var(--font-mono);
  font-size: 0.88em;
  color: var(--amber);
}

.table-scroll {
  width: 100%;
  overflow-x: auto;
  margin: 1rem 0 1.5rem;
  -webkit-overflow-scrolling: touch;
}
table.data {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.92rem;
  margin: 0;
  min-width: 28rem;
}
table.data th, table.data td {
  text-align: left;
  padding: 0.7rem 0.85rem;
  border-bottom: 1px solid var(--ink-line);
  vertical-align: top;
}
table.data th {
  font-family: var(--font-mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--amber);
  background: rgba(0,0,0,0.25);
}
table.data td { color: var(--paper-dim); }

/* FAQ */
.faq-list { max-width: var(--prose); }
.faq-item {
  border-bottom: 1px solid var(--ink-line);
  padding: 0.85rem 0;
}
.faq-item:first-child { border-top: 1px solid var(--ink-line); }
.faq-item h3, .faq-item summary {
  margin: 0;
  font-size: 1.02rem;
  color: var(--paper);
  cursor: pointer;
  list-style: none;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::before {
  content: "+";
  display: inline-block;
  width: 1.2rem;
  color: var(--amber);
  font-family: var(--font-mono);
}
.faq-item[open] summary::before { content: "−"; }
.faq-item p { margin: 0.65rem 0 0.25rem; color: var(--fog); }

/* Related / siblings */
.related {
  margin: 2.5rem 0 1rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--ink-line);
}
.related h2 { margin-top: 0; }
.chip-row { display: flex; flex-wrap: wrap; gap: 0.5rem; margin: 0.75rem 0; }
.chip {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.7rem;
  border-radius: 999px;
  border: 1px solid var(--ink-line);
  background: var(--ink-elev);
  color: var(--paper-dim);
  text-decoration: none;
  font-size: 0.85rem;
}
.chip:hover { border-color: var(--amber); color: var(--amber); }

/* CTA band */
.cta-band {
  margin: 2.5rem 0 0;
  padding: 1.5rem;
  border-radius: var(--radius);
  border: 1px solid rgba(232,168,56,0.3);
  background: linear-gradient(135deg, rgba(232,168,56,0.1), rgba(18,26,43,0.9));
}
.cta-band h2 { margin: 0 0 0.5rem; }
.cta-band p { margin: 0 0 1rem; color: var(--paper-dim); max-width: 36rem; }
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.65rem 1.1rem;
  border-radius: 8px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  border: 1px solid transparent;
  cursor: pointer;
}
.btn-primary {
  background: var(--amber);
  color: var(--ink);
}
.btn-primary:hover { background: #F0C06A; color: var(--ink); }
.btn-ghost {
  background: transparent;
  border-color: var(--ink-line);
  color: var(--paper);
}
.btn-ghost:hover { border-color: var(--amber); color: var(--amber); }

/* Footer */
.site-footer {
  border-top: 1px solid var(--ink-line);
  background: #080E18;
  padding: 2.5rem 0 2rem;
  color: var(--fog);
  font-size: 0.9rem;
}
.footer-grid {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
  margin-bottom: 1.75rem;
}
.site-footer h2 {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--paper-dim);
  margin: 0 0 0.65rem;
}
.site-footer ul { list-style: none; margin: 0; padding: 0; }
.site-footer li { margin-bottom: 0.35rem; }
.site-footer a { color: var(--fog); text-decoration: none; }
.site-footer a:hover { color: var(--amber); }
.disclaimer {
  border-top: 1px solid var(--ink-line);
  padding-top: 1.25rem;
  font-size: 0.8rem;
  color: var(--ink-muted);
  max-width: 48rem;
}
.disclaimer strong { color: var(--fog); }

/* 404 */
.error-page {
  text-align: center;
  padding: 4rem 0;
}
.error-page .code {
  font-family: var(--font-mono);
  font-size: clamp(4rem, 12vw, 7rem);
  color: var(--amber);
  line-height: 1;
  margin: 0;
  letter-spacing: -0.04em;
}
.empty-state {
  padding: 1.5rem;
  border: 1px dashed rgba(232,168,56,0.35);
  border-radius: var(--radius);
  color: var(--fog);
  text-align: center;
  background: rgba(0,0,0,0.15);
  max-width: 28rem;
  margin: 1.5rem auto;
}
.empty-state .empty-label {
  margin: 0 0 0.65rem;
  color: var(--amber);
  font-size: 0.8rem;
  letter-spacing: 0.06em;
}

.layout-split {
  display: grid;
  gap: 2rem;
}
@media (min-width: 960px) {
  .layout-split { grid-template-columns: minmax(0, 1fr) 16rem; align-items: start; }
  .sidebar { position: sticky; top: 5.5rem; }
}
.sidebar .panel { font-size: 0.9rem; }
.sidebar ul { margin: 0; padding-left: 1.1rem; color: var(--fog); }