/* ═══════════════════════════════════════════════════════════════
   selfdriven Foundation — Shared Stylesheet
   Used by: default.html, prose.html layouts
   ═══════════════════════════════════════════════════════════════ */

/* ─── Design tokens ──────────────────────────────────────────── */
:root {
  --bg:          #f5f2ed;
  --surface:     #edeae3;
  --surface2:    #e5e1d8;
  --border:      #ddd8ce;
  --text:        #1a1410;
  --muted:       #6b5f52;
  --muted2:      #9e9085;
  --accent:      #c8442f;
  --accent-dim:  rgba(200, 68, 47, 0.10);
  --card-radius: 20px;
  --shadow:      0 2px 16px rgba(0,0,0,0.07);
}
@media (prefers-color-scheme: dark) {
  :root {
    --bg:          #0a0a0a;
    --surface:     #161616;
    --surface2:    #1e1e1e;
    --border:      #242424;
    --text:        #f0ede8;
    --muted:       #b0b0b0;
    --muted2:      #666;
    --accent:      #e85d4a;
    --accent-dim:  rgba(232, 93, 74, 0.12);
    --shadow:      0 2px 16px rgba(0,0,0,0.4);
  }
}

/* ─── Reset & base ───────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { font-size: 16px; }
body {
  font-family: 'Poppins', 'Inter', system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
a { color: inherit; text-decoration: none; }

/* ─── Nav ────────────────────────────────────────────────────── */
nav {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  padding: 20px 40px;
  display: flex; align-items: center; justify-content: space-between;
  transition: background 0.3s, backdrop-filter 0.3s;
}
nav.scrolled {
  background: rgba(245,242,237,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
}
@media (prefers-color-scheme: dark) {
  nav.scrolled { background: rgba(10,10,10,0.92); }
}
.nav-logo img { height: 28px; width: auto; display: block; }
.nav-links { display: flex; gap: 28px; list-style: none; }
.nav-links a {
  font-size: 13px; font-weight: 500; letter-spacing: 0.02em;
  color: var(--muted); transition: color 0.2s;
}
.nav-links a:hover { color: var(--text); }

/* ─── Footer ─────────────────────────────────────────────────── */
footer {
  border-top: 1px solid var(--border);
  padding: 48px 40px;
  max-width: 1100px; margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
}
.footer-logo img { height: 16px; width: auto; opacity: 0.75; }
.footer-links { display: flex; gap: 24px; list-style: none; }
.footer-links a {
  font-size: 12px; color: var(--muted2); transition: color 0.2s;
}
.footer-links a:hover { color: var(--muted); }

/* ─── Hero (index page) ──────────────────────────────────────── */
.hero {
  padding: 160px 40px 80px;
  max-width: 1100px; margin: 0 auto;
}
.hero-eyebrow {
  font-size: 11px; font-weight: 600; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--accent); margin-bottom: 20px;
}
.hero h1 {
  font-size: clamp(48px, 7vw, 80px);
  font-weight: 800; letter-spacing: -0.04em; line-height: 1.05;
  margin-bottom: 28px;
}
.hero h1 em { color: var(--accent); font-style: italic; }
.hero-desc {
  font-size: 17px; color: var(--muted); line-height: 1.7;
  max-width: 560px;
}

/* ─── Stats ──────────────────────────────────────────────────── */
.stats {
  max-width: 1100px; margin: 0 auto; padding: 0 40px 80px;
  display: flex; gap: 48px;
}
.stat-num {
  font-size: 56px; font-weight: 800; letter-spacing: -0.04em; line-height: 1;
  margin-bottom: 8px;
}
.stat-num span { color: var(--accent); }
.stat-label { font-size: 13px; color: var(--muted); line-height: 1.5; }

/* ─── Grid (index page) ──────────────────────────────────────── */
.grid-section { max-width: 1100px; margin: 0 auto; padding: 0 40px; }
.grid-section-header {
  display: flex; align-items: baseline; justify-content: space-between;
  margin-bottom: 24px;
}
.grid-section-header h2 {
  font-size: 22px; font-weight: 700; letter-spacing: -0.03em;
}
.grid-section-header span { font-size: 12px; color: var(--muted2); }
.areas-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
.area-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--card-radius); padding: 28px 24px 24px;
  cursor: pointer; transition: transform 0.2s, box-shadow 0.2s;
  position: relative; overflow: hidden; box-shadow: var(--shadow);
}
.area-card::before {
  content: ''; position: absolute; top: 0; left: 0; right: 0; height: 3px;
  background: var(--accent);
  transform: scaleX(0); transform-origin: left; transition: transform 0.25s ease;
}
.area-card:hover, .area-card.active {
  transform: translateY(-3px);
  box-shadow: var(--shadow), 0 8px 32px rgba(0,0,0,0.12);
}
.area-card:hover::before, .area-card.active::before { transform: scaleX(1); }
.area-card-header {
  display: flex; align-items: flex-start;
  justify-content: space-between; margin-bottom: 12px;
}
.area-title { font-size: 15px; font-weight: 700; letter-spacing: -0.02em; }
.area-num {
  font-size: 11px; font-weight: 600; letter-spacing: 0.06em;
  color: var(--accent); background: var(--bg); border: 1px solid var(--border);
  border-radius: 999px; width: 32px; height: 32px;
  display: flex; align-items: center; justify-content: center; flex-shrink: 0;
}
.area-subtitle { font-size: 12px; color: var(--muted); line-height: 1.6; margin-bottom: 16px; }
.area-arrow { font-size: 16px; color: var(--muted2); transition: color 0.2s, transform 0.2s; }
.area-card:hover .area-arrow, .area-card.active .area-arrow {
  color: var(--accent); transform: translateX(3px);
}

/* ─── Detail panel ───────────────────────────────────────────── */
.detail-panel {
  max-width: 1100px; margin: 0 auto; padding: 0 40px;
  overflow: hidden; max-height: 0; transition: max-height 0.4s ease, padding 0.3s;
}
.detail-panel.open { max-height: 600px; padding: 16px 40px 0; }
.detail-inner {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--card-radius); padding: 48px;
}
.detail-header {
  display: flex; align-items: flex-start;
  justify-content: space-between; margin-bottom: 16px;
}
.detail-num {
  font-size: 72px; font-weight: 800; letter-spacing: -0.06em;
  line-height: 1; color: var(--border);
}
.detail-close {
  background: var(--bg); border: 1px solid var(--border);
  border-radius: 999px; width: 36px; height: 36px;
  cursor: pointer; color: var(--muted); font-size: 14px;
  display: flex; align-items: center; justify-content: center;
  transition: color 0.2s, border-color 0.2s;
}
.detail-close:hover { color: var(--text); border-color: var(--muted); }
.detail-title { font-size: 32px; font-weight: 800; letter-spacing: -0.04em; margin-bottom: 8px; }
.detail-tagline { font-size: 14px; color: var(--accent); font-style: italic; margin-bottom: 28px; }
.detail-body { font-size: 16px; color: var(--muted); line-height: 1.8; max-width: 680px; }

/* ─── Connections section ────────────────────────────────────── */
.connections-section { max-width: 1100px; margin: 0 auto; padding: 0 40px 120px; }
.connections-inner {
  background: var(--surface); border: 1px solid var(--border);
  padding: 48px; border-radius: var(--card-radius);
}
.section-label {
  font-size: 11px; font-weight: 600; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--accent); margin-bottom: 16px;
}
.connections-inner h2 {
  font-size: 28px; font-weight: 700; letter-spacing: -0.03em; margin-bottom: 20px;
}
.connections-inner > p {
  font-size: 15px; color: var(--muted); line-height: 1.8;
  max-width: 680px; margin-bottom: 32px;
}
.flow-row { display: flex; align-items: center; flex-wrap: wrap; row-gap: 8px; }
.flow-node {
  background: var(--bg); border: 1px solid var(--border);
  padding: 8px 16px; font-size: 12px; font-weight: 600; border-radius: 999px;
}
.flow-arrow { font-size: 14px; color: var(--muted2); padding: 0 8px; }

/* ═══════════════════════════════════════════════════════════════
   PROSE LAYOUT — long-form article / framework documents
   ═══════════════════════════════════════════════════════════════ */

/* Page wrapper */
.prose-page {
  padding-top: 120px;
  padding-bottom: 120px;
}

/* Two-column layout: TOC sidebar + article body */
.prose-container {
  max-width: 1100px; margin: 0 auto;
  padding: 0 40px;
  display: grid;
  grid-template-columns: 220px 1fr;
  gap: 64px;
  align-items: start;
}

/* ─── Eyebrow / page label ───────────────────────────────────── */
.prose-eyebrow {
  font-size: 11px; font-weight: 600; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--accent);
  max-width: 1100px; margin: 0 auto;
  padding: 0 40px 28px calc(40px + 220px + 64px);
}

/* ─── Sticky TOC sidebar ─────────────────────────────────────── */
.prose-toc {
  position: sticky; top: 88px;
  font-size: 12px; line-height: 1.6;
}
.prose-toc-label {
  font-size: 10px; font-weight: 700; letter-spacing: 0.12em;
  text-transform: uppercase; color: var(--muted2); margin-bottom: 16px;
}
.prose-toc ol {
  list-style: none; padding: 0; margin: 0;
  display: flex; flex-direction: column; gap: 2px;
}
.prose-toc li a {
  display: block; padding: 5px 10px;
  color: var(--muted); border-radius: 6px;
  transition: color 0.15s, background 0.15s;
  border-left: 2px solid transparent;
}
.prose-toc li a:hover,
.prose-toc li a.active {
  color: var(--text);
  background: var(--surface);
  border-left-color: var(--accent);
}
.prose-toc li.toc-sub a { padding-left: 20px; font-size: 11px; }

/* ─── Article body ───────────────────────────────────────────── */
.prose-body {
  min-width: 0; /* prevent grid blowout */
}

/* h1 — page title */
.prose-body h1 {
  font-size: clamp(32px, 4vw, 52px);
  font-weight: 800; letter-spacing: -0.04em; line-height: 1.08;
  margin-bottom: 28px;
}

/* Lead paragraph (first <p> after h1) */
.prose-body > p:first-of-type {
  font-size: 18px; color: var(--muted); line-height: 1.75;
  margin-bottom: 48px;
  padding-bottom: 48px;
  border-bottom: 1px solid var(--border);
}

/* Section separators via h2 */
.prose-body h2 {
  font-size: 26px; font-weight: 800; letter-spacing: -0.04em;
  margin-top: 72px; margin-bottom: 20px;
  padding-top: 72px;
  border-top: 1px solid var(--border);
  scroll-margin-top: 100px;
}
/* first h2 doesn't need top border/padding — lead paragraph provides the break */
.prose-body h2:first-of-type {
  border-top: none; padding-top: 0; margin-top: 0;
}

.prose-body h3 {
  font-size: 17px; font-weight: 700; letter-spacing: -0.025em;
  margin-top: 40px; margin-bottom: 12px; color: var(--text);
  scroll-margin-top: 100px;
}

.prose-body h4 {
  font-size: 13px; font-weight: 700; letter-spacing: 0.06em;
  text-transform: uppercase; color: var(--accent);
  margin-top: 28px; margin-bottom: 8px;
}

/* Body copy */
.prose-body p {
  font-size: 16px; color: var(--muted); line-height: 1.85;
  margin-bottom: 20px;
}

/* Bold inline */
.prose-body strong {
  font-weight: 700; color: var(--text);
}

/* Italic / emphasis */
.prose-body em { font-style: italic; }

/* Links */
.prose-body a {
  color: var(--accent);
  text-decoration: underline;
  text-decoration-color: var(--accent-dim);
  text-underline-offset: 3px;
  transition: text-decoration-color 0.2s;
}
.prose-body a:hover { text-decoration-color: var(--accent); }

/* Unordered lists */
.prose-body ul {
  list-style: none; padding: 0;
  margin: 0 0 24px 0;
  display: flex; flex-direction: column; gap: 6px;
}
.prose-body ul li {
  font-size: 15px; color: var(--muted); line-height: 1.7;
  padding-left: 20px; position: relative;
}
.prose-body ul li::before {
  content: '—';
  position: absolute; left: 0;
  color: var(--accent); font-weight: 600;
}

/* Ordered lists */
.prose-body ol {
  list-style: none; padding: 0; counter-reset: ol-counter;
  margin: 0 0 24px 0;
  display: flex; flex-direction: column; gap: 8px;
}
.prose-body ol li {
  font-size: 15px; color: var(--muted); line-height: 1.7;
  padding-left: 32px; position: relative;
  counter-increment: ol-counter;
}
.prose-body ol li::before {
  content: counter(ol-counter, decimal-leading-zero);
  position: absolute; left: 0;
  font-size: 11px; font-weight: 700; letter-spacing: 0.04em;
  color: var(--accent); top: 4px;
}

/* Horizontal rule */
.prose-body hr {
  border: none; border-top: 1px solid var(--border);
  margin: 64px 0;
}

/* Tables */
.prose-body table {
  width: 100%; border-collapse: collapse;
  margin: 32px 0; font-size: 14px;
  border-radius: var(--card-radius); overflow: hidden;
  border: 1px solid var(--border);
}
.prose-body thead tr {
  background: var(--surface2);
}
.prose-body thead th {
  text-align: left; padding: 14px 18px;
  font-size: 11px; font-weight: 700; letter-spacing: 0.08em;
  text-transform: uppercase; color: var(--muted2);
  border-bottom: 1px solid var(--border);
}
.prose-body tbody tr {
  border-bottom: 1px solid var(--border);
  transition: background 0.15s;
}
.prose-body tbody tr:last-child { border-bottom: none; }
.prose-body tbody tr:hover { background: var(--surface); }
.prose-body tbody td {
  padding: 14px 18px; color: var(--muted); vertical-align: top;
  line-height: 1.6;
}
.prose-body tbody td:first-child { font-weight: 600; color: var(--text); }

/* Blockquote — used for callouts/summaries */
.prose-body blockquote {
  margin: 36px 0;
  padding: 28px 32px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--accent);
  border-radius: 0 var(--card-radius) var(--card-radius) 0;
}
.prose-body blockquote p {
  font-size: 17px; font-style: italic; color: var(--text);
  line-height: 1.75; margin: 0;
}

/* Inline code */
.prose-body code {
  font-family: 'SF Mono', 'Fira Code', ui-monospace, monospace;
  font-size: 13px; background: var(--surface2);
  border: 1px solid var(--border); border-radius: 5px;
  padding: 2px 6px; color: var(--accent);
}

/* Code blocks */
.prose-body pre {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--card-radius); padding: 28px 32px;
  overflow-x: auto; margin: 24px 0;
}
.prose-body pre code {
  background: none; border: none; padding: 0; color: var(--text);
  font-size: 13px; line-height: 1.7;
}

/* ─── Layer / step list pattern (numbered bold items) ────────── */
/* Used for "Layer 1: ... Layer 2: ..." style content */
.prose-body p + p > strong:first-child {
  /* Intentionally not floated — kept inline */
}

/* ─── Stacked list cards — Definition-style content ─────────── */
/* Wraps around groups of h3 + content as visual cards */
.prose-section-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--card-radius);
  padding: 36px 40px;
  margin: 24px 0;
}
.prose-section-card h3 {
  margin-top: 0;
}

/* ─── Footer nav (prev/next links) ──────────────────────────── */
.prose-footer-nav {
  max-width: 1100px; margin: 0 auto;
  padding: 48px 40px;
  display: flex; justify-content: space-between; align-items: center;
  border-top: 1px solid var(--border);
  gap: 16px;
}
.prose-footer-nav a {
  display: inline-flex; align-items: center; gap: 8px;
  font-size: 13px; font-weight: 600; color: var(--muted);
  padding: 10px 18px;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 999px; transition: color 0.2s, border-color 0.2s;
}
.prose-footer-nav a:hover { color: var(--text); border-color: var(--muted); }

/* ═══════════════════════════════════════════════════════════════
   RESPONSIVE
   ═══════════════════════════════════════════════════════════════ */
@media (max-width: 900px) {
  .areas-grid { grid-template-columns: repeat(2, 1fr); }
  .stats { flex-wrap: wrap; }
  .stat { flex: 0 0 45%; }
  .prose-container { grid-template-columns: 1fr; gap: 0; }
  .prose-toc { display: none; }
  .prose-eyebrow { padding-left: 40px; }
}
@media (max-width: 600px) {
  nav { padding-left: 20px; padding-right: 20px; }
  .nav-links { display: none; }
  .hero { padding: 120px 20px 60px; }
  .stats { padding: 0 20px 60px; }
  .grid-section, .detail-panel, .connections-section { padding-left: 20px; padding-right: 20px; }
  .areas-grid { grid-template-columns: 1fr; }
  .detail-inner, .connections-inner { padding: 28px 20px; }
  .detail-num { font-size: 48px; }
  footer { flex-direction: column; gap: 24px; align-items: flex-start; padding: 40px 20px; }
  .prose-page { padding-top: 88px; }
  .prose-container { padding: 0 20px; }
  .prose-eyebrow { padding: 0 20px 20px; }
  .prose-body h1 { font-size: 28px; }
  .prose-body h2 { font-size: 22px; }
  .prose-body table { font-size: 12px; }
  .prose-body thead th,
  .prose-body tbody td { padding: 10px 12px; }
  .prose-footer-nav { padding: 32px 20px; flex-direction: column; }
}