/* ============================================================
   Field Notes — The Precheck Cut
   Shared theme. Matches "The Mech Suit Methodology" parent article.
   Aesthetic: Instrumented Void — obsidian, monospace, tonal layering.
   ============================================================ */

:root {
  --bg: #14171e;
  --bg-raised: #1c2029;
  --bg-panel: #222738;
  --bg-excerpt: #181b23;
  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-accent: rgba(120, 160, 220, 0.22);
  --intent-mark: #7aa7ff;
  --ink: #e5e8ef;
  --ink-dim: #a4abba;
  --ink-muted: #6b7380;
  --accent: #9cc4ff;
  --accent-warm: #ffb46b;
  --accent-good: #7fdba3;
  --accent-warn: #f2c65c;
  --accent-alarm: #f08a7d;
  --receipt: #c7a3ff;

  --font-body: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
  --font-mono: "JetBrains Mono", "SF Mono", Menlo, Consolas, monospace;

  --measure: 72ch;
}

* {
  box-sizing: border-box;
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

body {
  background-image:
    radial-gradient(ellipse at top, rgba(40, 60, 100, 0.08), transparent 60%),
    radial-gradient(ellipse at bottom, rgba(80, 40, 100, 0.04), transparent 60%);
  background-attachment: fixed;
}

/* ---------- Layout ---------- */

.page {
  max-width: 860px;
  margin: 0 auto;
  padding: 48px 32px 96px;
}

.breadcrumb {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--ink-muted);
  margin-bottom: 48px;
}

.breadcrumb a {
  color: var(--ink-dim);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.breadcrumb a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

/* ---------- Masthead ---------- */

.masthead {
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
  padding: 24px 0 32px;
  margin-bottom: 48px;
}

.masthead .series-tag {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--ink-muted);
  margin-bottom: 12px;
}

.masthead .post-number {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--intent-mark);
  letter-spacing: 0.1em;
  margin-bottom: 8px;
}

.masthead h1 {
  font-size: 38px;
  line-height: 1.15;
  margin: 8px 0 16px;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.masthead .subtitle {
  font-size: 18px;
  color: var(--ink-dim);
  line-height: 1.5;
  margin: 0;
  font-style: italic;
}

.masthead .byline {
  margin-top: 24px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-muted);
  letter-spacing: 0.04em;
}

/* ---------- Prose ---------- */

.prose {
  max-width: var(--measure);
}

.prose p {
  margin: 0 0 1.25em;
  color: var(--ink);
}

.prose p.lede {
  font-size: 19px;
  color: var(--ink-dim);
  line-height: 1.55;
  margin-bottom: 2em;
}

.prose h2 {
  font-size: 24px;
  margin: 56px 0 16px;
  font-weight: 700;
  letter-spacing: -0.005em;
  position: relative;
  padding-left: 16px;
}

.prose h2::before {
  content: "";
  position: absolute;
  left: 0;
  top: 8px;
  bottom: 8px;
  width: 2px;
  background: var(--intent-mark);
  opacity: 0.8;
}

.prose h3 {
  font-size: 18px;
  margin: 36px 0 12px;
  font-weight: 700;
  color: var(--ink);
}

.prose a {
  color: var(--accent);
  text-decoration: none;
  border-bottom: 1px solid rgba(156, 196, 255, 0.3);
}

.prose a:hover {
  border-bottom-color: var(--accent);
}

.prose strong {
  color: #fff;
  font-weight: 600;
}

.prose em {
  color: var(--ink-dim);
}

.prose ul, .prose ol {
  margin: 0 0 1.25em;
  padding-left: 24px;
}

.prose li {
  margin-bottom: 0.5em;
}

.prose code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background: var(--bg-raised);
  border: 1px solid var(--border-subtle);
  padding: 1px 6px;
  border-radius: 3px;
  color: var(--accent);
}

/* ---------- Receipt (verbatim excerpt from the repo) ---------- */

.receipt {
  margin: 32px 0;
  background: var(--bg-excerpt);
  border-left: 2px solid var(--receipt);
  border-radius: 0 4px 4px 0;
  overflow: hidden;
}

.receipt-header {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--receipt);
  padding: 10px 16px 6px;
  text-transform: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  border-bottom: 1px solid rgba(199, 163, 255, 0.12);
}

.receipt-header .label {
  opacity: 0.7;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-size: 10px;
}

.receipt-header .path {
  color: var(--ink-dim);
  font-size: 11px;
}

.receipt-body {
  padding: 16px 20px;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 1.6;
  color: var(--ink);
  white-space: pre-wrap;
  overflow-x: auto;
}

.receipt-body.prose-like {
  font-family: var(--font-body);
  font-size: 15px;
  white-space: normal;
  color: var(--ink-dim);
  font-style: italic;
}

/* ---------- Callouts ---------- */

.callout {
  margin: 32px 0;
  padding: 20px 24px;
  background: var(--bg-panel);
  border-left: 3px solid var(--accent);
  border-radius: 0 4px 4px 0;
}

.callout .callout-label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  margin-bottom: 8px;
  font-weight: 700;
}

.callout p {
  margin: 0;
  color: var(--ink);
  font-size: 16px;
  line-height: 1.6;
}

.callout p + p {
  margin-top: 0.8em;
}

.callout.insight { border-left-color: var(--accent); }
.callout.insight .callout-label { color: var(--accent); }

.callout.unlock { border-left-color: var(--accent-good); }
.callout.unlock .callout-label { color: var(--accent-good); }

.callout.limitation { border-left-color: var(--accent-warn); }
.callout.limitation .callout-label { color: var(--accent-warn); }

.callout.honest { border-left-color: var(--accent-warm); }
.callout.honest .callout-label { color: var(--accent-warm); }

/* ---------- Cold open ---------- */

.cold-open {
  margin: 0 0 40px;
  padding: 28px 32px;
  background: linear-gradient(180deg, rgba(122, 167, 255, 0.05), transparent);
  border-top: 1px solid var(--border-subtle);
  border-bottom: 1px solid var(--border-subtle);
  font-size: 19px;
  line-height: 1.55;
  color: var(--ink);
  font-style: italic;
}

.cold-open p:last-child {
  margin-bottom: 0;
}

/* ---------- Footer navigation ---------- */

.post-footer {
  margin-top: 80px;
  padding-top: 40px;
  border-top: 1px solid var(--border-subtle);
}

.prev-next {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 40px;
}

.prev-next a {
  display: block;
  padding: 16px 20px;
  background: var(--bg-raised);
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  text-decoration: none;
  color: var(--ink);
  transition: border-color 0.15s, background 0.15s;
}

.prev-next a:hover {
  border-color: var(--border-accent);
  background: var(--bg-panel);
}

.prev-next .direction {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-muted);
  display: block;
  margin-bottom: 6px;
}

.prev-next .title {
  font-size: 15px;
  color: var(--ink);
  line-height: 1.35;
  display: block;
}

.prev-next .next {
  text-align: right;
}

.prev-next .placeholder {
  background: transparent;
  border: 1px dashed var(--border-subtle);
  opacity: 0.3;
  pointer-events: none;
}

.toc-footer {
  margin-top: 40px;
  padding: 24px 0;
  border-top: 1px solid var(--border-subtle);
}

.toc-footer .toc-heading {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-muted);
  margin-bottom: 16px;
}

.toc-footer ol {
  list-style: none;
  padding: 0;
  margin: 0;
  counter-reset: toc;
}

.toc-footer li {
  counter-increment: toc;
  padding: 6px 0;
  font-size: 14px;
}

.toc-footer li::before {
  content: counter(toc, decimal-leading-zero);
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-muted);
  margin-right: 14px;
  letter-spacing: 0.08em;
}

.toc-footer a {
  color: var(--ink-dim);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.toc-footer a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.toc-footer .current {
  color: var(--ink);
}

.toc-footer .parent-link {
  margin-top: 24px;
  padding-top: 20px;
  border-top: 1px solid var(--border-subtle);
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--ink-muted);
}

.toc-footer .parent-link a {
  color: var(--intent-mark);
}

/* ---------- Index page specifics ---------- */

.index-intro {
  max-width: var(--measure);
  margin-bottom: 56px;
}

.index-intro h1 {
  font-size: 42px;
  margin: 8px 0 20px;
  line-height: 1.1;
}

.index-intro .subtitle {
  font-size: 20px;
  color: var(--ink-dim);
  font-style: italic;
  line-height: 1.5;
}

.index-intro .framing {
  margin-top: 32px;
  font-size: 17px;
  color: var(--ink);
}

.index-list {
  list-style: none;
  padding: 0;
  margin: 0 0 64px;
  counter-reset: index;
}

.index-list li {
  counter-increment: index;
  padding: 28px 0;
  border-bottom: 1px solid var(--border-subtle);
}

.index-list li:first-child {
  border-top: 1px solid var(--border-subtle);
}

.index-list .entry-number {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  color: var(--intent-mark);
  display: block;
  margin-bottom: 6px;
}

.index-list .entry-number::before {
  content: counter(index, decimal-leading-zero) " · ";
}

.index-list .entry-title {
  font-size: 22px;
  font-weight: 700;
  line-height: 1.25;
  margin: 4px 0 8px;
}

.index-list .entry-title a {
  color: var(--ink);
  text-decoration: none;
  border-bottom: 1px solid transparent;
}

.index-list .entry-title a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

.index-list .entry-hook {
  color: var(--ink-dim);
  font-size: 16px;
  line-height: 1.55;
  margin: 0 0 10px;
  max-width: var(--measure);
}

.index-list .entry-meta {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.06em;
  color: var(--ink-muted);
  display: flex;
  gap: 20px;
  flex-wrap: wrap;
}

.index-list .entry-meta .artifact {
  color: var(--receipt);
  opacity: 0.7;
}

.index-download {
  margin-top: 48px;
  padding: 24px 28px;
  background: var(--bg-panel);
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  text-align: center;
}

.index-download .download-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--ink-muted);
  margin-bottom: 8px;
}

.index-download p {
  margin: 4px 0 0;
  color: var(--ink-dim);
  font-size: 14px;
}

/* ---------- Responsive ---------- */

@media (max-width: 640px) {
  .page { padding: 32px 20px 64px; }
  .masthead h1 { font-size: 30px; }
  .index-intro h1 { font-size: 32px; }
  .prev-next { grid-template-columns: 1fr; }
  .prev-next .next { text-align: left; }
  .prose { font-size: 16px; }
}