/* ============================================================
   Reflexive TA Toolkit — design preview
   Visual language ported from redesign.html
   ============================================================ */

:root {
  color-scheme: light;
  --bg: #f7f6f3;
  --surface: #ffffff;
  --fg: #1a1a1a;
  --muted: #5c5c5c;
  --border: #e0ddd7;
  --accent: #2d6a4f;
  --accent-deep: #1b4332;
  --accent-soft: #d8f3dc;
  --nav-bg: rgba(247, 246, 243, 0.88);
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.08);
  --warn: #b45309;
  --warn-soft: #fef3c7;

  --font-display: 'Iowan Old Style', Georgia, 'Times New Roman', serif;
  --font-body: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  --font-mono: ui-monospace, 'SF Mono', Menlo, monospace;

  --page-width: 1100px;
  --gutter: clamp(1.25rem, 4vw, 3rem);
  --section-space: clamp(5rem, 10vw, 8rem);
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #121212;
  --surface: #1e1e1e;
  --fg: #e8e8e8;
  --muted: #a0a0a0;
  --border: #333333;
  --accent: #52b788;
  --accent-deep: #74c69d;
  --accent-soft: #1b4332;
  --nav-bg: rgba(18, 18, 18, 0.88);
  --shadow: 0 24px 70px rgba(0, 0, 0, 0.28);
  --warn: #fbbf24;
  --warn-soft: #422006;
}

/* ============================================================
   Reset & base
   ============================================================ */

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 5rem;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background 200ms ease, color 200ms ease;
}

img, svg { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; cursor: pointer; }

::selection {
  background: var(--accent);
  color: #fff;
}

.skip-link {
  position: fixed;
  top: 0.75rem;
  left: 0.75rem;
  z-index: 1000;
  padding: 0.7rem 1rem;
  background: var(--fg);
  color: var(--bg);
  text-decoration: none;
  transform: translateY(-160%);
  transition: transform 160ms ease;
  border-radius: 6px;
  font-size: 0.85rem;
  font-weight: 500;
}
.skip-link:focus { transform: translateY(0); }

/* ============================================================
   Header / nav
   ============================================================ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid var(--border);
  background: var(--nav-bg);
  backdrop-filter: blur(18px);
  -webkit-backdrop-filter: blur(18px);
}

.site-header__inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  width: min(100%, var(--page-width));
  min-height: 4.5rem;
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  width: max-content;
}
.wordmark__mark {
  display: grid;
  width: 2.1rem;
  aspect-ratio: 1;
  place-items: center;
  border: 1px solid var(--border);
  border-radius: 50%;
  color: var(--accent);
  font-family: var(--font-display);
  font-size: 0.9rem;
  font-weight: 600;
}
.wordmark__title {
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 500;
  color: var(--fg);
}
.wordmark__sub {
  display: block;
  font-family: var(--font-body);
  font-size: 0.65rem;
  color: var(--muted);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.site-nav {
  display: flex;
  align-items: center;
  gap: clamp(1rem, 2.5vw, 2.25rem);
}
.site-nav a {
  position: relative;
  color: var(--muted);
  font-size: 0.85rem;
  font-weight: 500;
  letter-spacing: 0.04em;
}
.site-nav a::after {
  position: absolute;
  right: 0;
  bottom: -0.5rem;
  left: 0;
  height: 1.5px;
  background: var(--accent);
  content: "";
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 180ms ease;
}
.site-nav a:hover::after,
.site-nav a.is-current::after { transform: scaleX(1); }

.theme-toggle {
  justify-self: end;
  display: grid;
  width: 2.4rem;
  aspect-ratio: 1;
  padding: 0.55rem;
  border: 1px solid var(--border);
  border-radius: 50%;
  background: transparent;
  color: var(--fg);
  place-items: center;
  transition: border-color 180ms ease, color 180ms ease, transform 180ms ease;
}
.theme-toggle:hover {
  border-color: var(--accent);
  color: var(--accent);
  transform: rotate(8deg);
}
.theme-toggle svg { grid-area: 1 / 1; width: 1.2rem; }
.theme-toggle__sun,
[data-theme="dark"] .theme-toggle__moon {
  opacity: 0;
  transform: rotate(-45deg) scale(0.7);
}
[data-theme="dark"] .theme-toggle__sun {
  opacity: 1;
  transform: rotate(0) scale(1);
}
.theme-toggle svg { transition: opacity 180ms ease, transform 180ms ease; }

/* ============================================================
   Generic page section chrome
   ============================================================ */

.page-section {
  width: min(100%, var(--page-width));
  margin: 0 auto;
  padding: var(--section-space) var(--gutter) 0;
}

.section-heading {
  display: grid;
  grid-template-columns: minmax(10rem, 0.4fr) minmax(0, 1fr);
  gap: clamp(2rem, 6vw, 6rem);
  margin-bottom: clamp(2.5rem, 5vw, 4.5rem);
  padding-top: 1.2rem;
  border-top: 1.5px solid var(--border);
}
.section-heading > div:first-child {
  display: flex;
  gap: 1rem;
  align-items: baseline;
}
.section-heading__number {
  color: var(--accent);
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
}
.eyebrow {
  margin: 0;
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.11em;
  text-transform: uppercase;
}
.section-heading h2 {
  max-width: 16ch;
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2.4rem, 5vw, 4.5rem);
  font-weight: 600;
  letter-spacing: -0.04em;
  line-height: 0.98;
}
.section-heading > div:last-child > p {
  max-width: 50ch;
  margin: 1.2rem 0 0;
  color: var(--muted);
  font-size: 1.05rem;
}

/* ============================================================
   Hero
   ============================================================ */

.hero {
  width: min(100%, var(--page-width));
  margin: 0 auto;
  padding: clamp(4rem, 8vw, 7rem) var(--gutter) 0;
}
.hero__inner {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 0.8fr);
  gap: clamp(2.5rem, 6vw, 5rem);
  align-items: center;
}
.hero__copy { max-width: 46rem; }
.hero__eyebrow {
  display: inline-flex;
  gap: 0.6rem;
  align-items: center;
  margin: 0 0 1.2rem;
  padding: 0.4rem 0.7rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.hero__eyebrow .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--accent);
}
.hero h1 {
  max-width: 14ch;
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(3rem, 6.5vw, 5.5rem);
  font-weight: 600;
  letter-spacing: -0.04em;
  line-height: 0.95;
}
.hero__role {
  margin: 1.5rem 0 0;
  color: var(--muted);
  font-size: clamp(1rem, 1.8vw, 1.15rem);
}
.hero__lead {
  max-width: 36ch;
  margin: 1.8rem 0 0;
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 2.8vw, 2rem);
  letter-spacing: -0.02em;
  line-height: 1.15;
}
.hero__bio {
  max-width: 56ch;
  margin: 1.2rem 0 0;
  color: var(--muted);
  font-size: 1.05rem;
  line-height: 1.65;
}
.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
  margin-top: 2rem;
}

.button {
  display: inline-flex;
  gap: 0.6rem;
  align-items: center;
  min-height: 3rem;
  padding: 0.75rem 1.25rem;
  border: 1.5px solid var(--accent);
  background: var(--accent);
  color: #fff;
  font-size: 0.88rem;
  font-weight: 600;
  border-radius: 6px;
  transition: background 180ms ease, border-color 180ms ease, transform 180ms ease;
}
.button:hover {
  background: var(--accent-deep);
  border-color: var(--accent-deep);
  transform: translateY(-2px);
}
.button--secondary {
  background: transparent;
  color: var(--accent);
}
.button--secondary:hover {
  background: var(--accent);
  color: #fff;
}
.button svg, .text-link svg { width: 1.1rem; flex: 0 0 auto; transition: transform 180ms ease; }
.button:hover svg, .text-link:hover svg { transform: translateX(0.2rem); }

.text-link {
  display: inline-flex;
  gap: 0.5rem;
  align-items: center;
  color: var(--fg);
  font-size: 0.88rem;
  font-weight: 600;
  text-decoration: underline;
  text-decoration-color: var(--border);
  text-underline-offset: 0.3rem;
  text-decoration-thickness: 1.5px;
}
.text-link:hover { color: var(--accent); text-decoration-color: var(--accent); }

.hero__panel {
  padding: 1.6rem;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
  box-shadow: var(--shadow);
}
.hero__panel h3 {
  margin: 0 0 0.6rem;
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
}
.hero__panel-list {
  margin: 0;
  padding: 0;
  list-style: none;
  border-top: 1px solid var(--border);
}
.hero__panel-list li {
  display: grid;
  grid-template-columns: 1.4rem 1fr;
  gap: 0.6rem;
  padding: 0.7rem 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
}
.hero__panel-list li:last-child { border-bottom: 0; }
.hero__panel-list li span:first-child {
  color: var(--accent);
  font-family: var(--font-display);
  font-weight: 600;
}

/* ============================================================
   Method — phase comparison
   ============================================================ */

.phases {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
  background: var(--surface);
}
.phases__col {
  padding: 1.6rem 1.6rem 0.5rem;
}
.phases__col h3 {
  margin: 0 0 0.4rem;
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
}
.phases__col p.col-sub {
  margin: 0 0 1rem;
  color: var(--muted);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.phases__col + .phases__col { border-left: 1px solid var(--border); }
.phases__list {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: phase;
}
.phases__list li {
  display: grid;
  grid-template-columns: 1.6rem 1fr;
  gap: 0.6rem;
  padding: 0.85rem 0;
  border-top: 1px solid var(--border);
  font-size: 0.92rem;
  line-height: 1.45;
}
.phases__list li::before {
  counter-increment: phase;
  content: counter(phase);
  color: var(--accent);
  font-family: var(--font-display);
  font-weight: 600;
}
.phases__list li strong {
  display: block;
  color: var(--fg);
  font-family: var(--font-display);
  font-weight: 600;
}
.phases__list li span {
  color: var(--muted);
  font-size: 0.85rem;
}

.focus-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
  margin-top: 2rem;
}
.focus-card {
  padding: 1.4rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--surface);
}
.focus-card__icon {
  display: grid;
  width: 2.4rem;
  aspect-ratio: 1;
  border: 1px solid var(--border);
  border-radius: 50%;
  color: var(--accent);
  place-items: center;
  margin-bottom: 0.8rem;
}
.focus-card__icon svg { width: 1.1rem; }
.focus-card h3 {
  margin: 0 0 0.4rem;
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 600;
}
.focus-card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.88rem;
  line-height: 1.5;
}

/* ============================================================
   Pipeline walkthrough — one paragraph, seven stages
   ============================================================ */

.flow-walkthrough {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 0.8rem;
  margin-top: 1.5rem;
}

.flow-card {
  position: relative;
  padding: 1rem 1rem 0.9rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--surface);
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.flow-card__head {
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border);
}
.flow-card__num {
  color: var(--accent);
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 600;
  flex: 0 0 auto;
}
.flow-card__name {
  font-family: var(--font-display);
  font-size: 0.98rem;
  font-weight: 600;
  color: var(--fg);
}
.flow-card__summary {
  color: var(--muted);
  font-size: 0.8rem;
  line-height: 1.45;
}
.flow-card__data {
  font-size: 0.85rem;
  line-height: 1.5;
  flex: 1;
}
.flow-card__data blockquote {
  margin: 0;
  padding: 0.5rem 0.7rem;
  border-left: 2px solid var(--accent);
  background: var(--accent-soft);
  font-family: var(--font-display);
  font-style: italic;
  font-size: 0.85rem;
  border-radius: 0 4px 4px 0;
  line-height: 1.45;
}
.flow-card__data .structure-label,
.flow-card__data .excerpt-label,
.flow-card__data .merge-label,
.flow-card__data .theme-label {
  display: block;
  color: var(--accent);
  font-family: var(--font-display);
  font-weight: 600;
  margin-bottom: 0.3rem;
  font-size: 0.88rem;
}
.flow-card__data .gist {
  margin: 0.3rem 0 0;
  color: var(--fg);
  font-family: var(--font-display);
  font-size: 0.88rem;
  line-height: 1.45;
}
.flow-card__data .codes {
  display: grid;
  gap: 0.5rem;
}
.flow-card__data .code-line {
  display: grid;
  grid-template-columns: 2.2rem 1fr;
  gap: 0.5rem;
  align-items: baseline;
  padding: 0.4rem 0.5rem;
  background: var(--bg);
  border-radius: 6px;
}
.flow-card__data .code-line .who {
  font-family: var(--font-display);
  font-weight: 600;
  color: var(--accent);
  font-size: 0.8rem;
}
.flow-card__data .code-line .badge {
  display: inline-block;
  padding: 0.05rem 0.4rem;
  margin-right: 0.3rem;
  border-radius: 999px;
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  vertical-align: 0.05rem;
}
.flow-card__data .code-line .badge.semantic { background: var(--accent-soft); color: var(--accent-deep); }
.flow-card__data .code-line .badge.latent { background: var(--warn-soft); color: var(--warn); }
[data-theme="dark"] .flow-card__data .code-line .badge.semantic { color: var(--accent); }
[data-theme="dark"] .flow-card__data .code-line .badge.latent { color: var(--warn); }
.flow-card__data .code-line .label-text { font-size: 0.85rem; }
.flow-card__data .verify-pass {
  display: inline-block;
  margin-bottom: 0.3rem;
  padding: 0.1rem 0.5rem;
  background: var(--accent-soft);
  color: var(--accent);
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.flow-card__data .merge-action {
  display: inline-block;
  margin-bottom: 0.4rem;
  padding: 0.1rem 0.5rem;
  background: var(--accent);
  color: #fff;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-right: 0.4rem;
}
.flow-card__data .merge-rationale,
.flow-card__data .theme-statement {
  margin: 0.3rem 0 0;
  font-size: 0.85rem;
  line-height: 1.5;
  color: var(--fg);
}
.flow-card__data .theme-statement { font-family: var(--font-display); }
.flow-card__meta {
  display: block;
  color: var(--muted);
  font-size: 0.74rem;
  margin-top: 0.3rem;
  font-family: var(--font-mono);
  line-height: 1.4;
}
.flow-card__editable {
  position: absolute;
  top: 0.7rem;
  right: 0.8rem;
  font-size: 0.65rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
  font-family: var(--font-mono);
}
.flow-card__editable.yes { color: var(--accent); }
.flow-card__editable::before { content: "editable · "; opacity: 0.7; }

/* ============================================================
   Locked decisions table
   ============================================================ */

.decisions__filters {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0 0 1rem;
}
.decisions__filters button {
  padding: 0.4rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  transition: all 180ms ease;
}
.decisions__filters button:hover { color: var(--fg); border-color: var(--fg); }
.decisions__filters button.is-active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.decisions { border-top: 1px solid var(--border); }
.decision {
  border-bottom: 1px solid var(--border);
}
.decision__head {
  display: grid;
  grid-template-columns: 2.5rem 4rem 1fr auto;
  gap: 1rem;
  align-items: baseline;
  width: 100%;
  padding: 1.2rem 0;
  background: transparent;
  border: 0;
  text-align: left;
  color: var(--fg);
}
.decision__num {
  color: var(--accent);
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 600;
}
.decision__cat {
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.decision__title {
  font-family: var(--font-display);
  font-size: 1.1rem;
  font-weight: 600;
  line-height: 1.3;
}
.decision__chev {
  color: var(--muted);
  font-size: 1.2rem;
  transition: transform 180ms ease;
}
.decision[open] .decision__chev { transform: rotate(90deg); }

.decision__body {
  padding: 0 0 1.6rem;
  display: grid;
  gap: 1rem;
}
.decision__tabs {
  display: flex;
  gap: 0.2rem;
  border-bottom: 1px solid var(--border);
  margin-bottom: 0.4rem;
}
.decision__tabs button {
  padding: 0.5rem 0.8rem;
  background: transparent;
  border: 0;
  border-bottom: 2px solid transparent;
  color: var(--muted);
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: -1px;
  transition: all 180ms ease;
}
.decision__tabs button.is-active {
  color: var(--accent);
  border-bottom-color: var(--accent);
}
.decision__panel {
  display: none;
  padding: 0.4rem 0;
  color: var(--fg);
  font-size: 0.95rem;
  line-height: 1.6;
}
.decision__panel.is-active { display: block; }
.decision__panel blockquote {
  margin: 0;
  padding: 0.8rem 1rem;
  border-left: 3px solid var(--accent);
  background: var(--accent-soft);
  color: var(--fg);
  border-radius: 0 6px 6px 0;
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-style: italic;
}
[data-theme="dark"] .decision__panel blockquote { color: var(--fg); }
.decision__panel p { margin: 0 0 0.6rem; }
.decision__panel p:last-child { margin-bottom: 0; }
.decision__panel .citation {
  display: block;
  margin-top: 0.6rem;
  color: var(--muted);
  font-size: 0.78rem;
  font-style: italic;
}
.decision__panel pre {
  margin: 0;
  padding: 0.8rem 1rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 6px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.5;
}
.decision__panel code { font-family: var(--font-mono); font-size: 0.88em; background: var(--accent-soft); padding: 0.05em 0.3em; border-radius: 3px; }
[data-theme="dark"] .decision__panel code { background: var(--accent-soft); }

/* ============================================================
   Deep dives
   ============================================================ */

.dive {
  margin-bottom: 2.5rem;
  padding: 1.8rem;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface);
}
.dive__head {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  margin-bottom: 1rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--border);
}
.dive__title {
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: 600;
  letter-spacing: -0.02em;
}
.dive__sub {
  display: block;
  color: var(--muted);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-top: 0.2rem;
}
.dive__actions { display: flex; gap: 0.5rem; }
.dive__actions .button {
  min-height: 2.4rem;
  padding: 0.5rem 0.9rem;
  font-size: 0.78rem;
}

/* Worked example stepper */
.stepper {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.2rem;
}
.stepper__col { min-width: 0; }
.stepper__col h4 {
  margin: 0 0 0.6rem;
  color: var(--muted);
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.transcript {
  max-height: 600px;
  overflow-y: auto;
  padding: 0.8rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  line-height: 1.5;
}
.transcript p { margin: 0 0 0.4rem; cursor: pointer; padding: 0.2rem 0.4rem; border-radius: 4px; transition: background 150ms ease; }
.transcript p:hover { background: var(--accent-soft); }
.transcript p.is-active { background: var(--accent); color: #fff; }
.transcript p .speaker { color: var(--accent); font-weight: 600; margin-right: 0.4rem; }
.transcript p.is-active .speaker { color: #fff; }

.artifact {
  max-height: 600px;
  overflow-y: auto;
  padding: 0.4rem;
}
.artifact-step {
  padding: 0.8rem 1rem;
  margin-bottom: 0.6rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg);
  opacity: 0.35;
  transition: all 200ms ease;
}
.artifact-step.is-active {
  opacity: 1;
  border-color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent-soft);
}
.artifact-step h5 {
  margin: 0 0 0.4rem;
  color: var(--accent);
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 600;
}
.artifact-step .meta {
  display: block;
  color: var(--muted);
  font-size: 0.72rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-bottom: 0.4rem;
}
.artifact-step p {
  margin: 0 0 0.4rem;
  font-size: 0.88rem;
  line-height: 1.5;
}
.artifact-step blockquote {
  margin: 0.4rem 0;
  padding: 0.5rem 0.8rem;
  border-left: 2px solid var(--accent);
  background: var(--accent-soft);
  font-family: var(--font-display);
  font-style: italic;
  font-size: 0.88rem;
  border-radius: 0 4px 4px 0;
}
.artifact-step .rationale {
  display: block;
  margin-top: 0.4rem;
  color: var(--muted);
  font-size: 0.82rem;
  font-style: italic;
}
.artifact-step .badge {
  display: inline-block;
  padding: 0.1rem 0.5rem;
  margin-right: 0.3rem;
  border-radius: 999px;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.badge.semantic { background: var(--accent-soft); color: var(--accent-deep); }
.badge.latent { background: var(--warn-soft); color: var(--warn); }
[data-theme="dark"] .badge.semantic { color: var(--accent); }
[data-theme="dark"] .badge.latent { color: var(--warn); }
.badge.merge { background: var(--accent); color: #fff; }
.badge.human { background: var(--accent); color: #fff; }
.badge.memo { background: var(--warn-soft); color: var(--warn); }
.artifact-step:has(.badge.human) { border-left: 3px solid var(--accent); }

/* Architecture & scale */
.arch-subhead {
  margin: 2.4rem 0 1rem;
  font-size: 1.05rem;
}
.rail-intro {
  margin: 0 0 1.2rem;
  color: var(--muted);
  font-size: 0.92rem;
  line-height: 1.55;
  max-width: 70ch;
}
.rail {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr));
  gap: 0.8rem;
}
.rail-node {
  position: relative;
  padding: 1rem 1rem 0.9rem;
  border: 1px solid var(--border, rgba(127,127,127,0.25));
  border-radius: 12px;
  background: var(--surface, transparent);
}
.rail-node.is-pause { border-style: dashed; border-color: var(--accent); }
.rail-node__num {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  color: var(--muted);
  margin-bottom: 0.25rem;
}
.rail-node__name {
  display: block;
  font-weight: 650;
  font-size: 0.92rem;
  margin-bottom: 0.45rem;
}
.rail-node__io {
  display: block;
  font-size: 0.76rem;
  color: var(--muted);
  line-height: 1.45;
}
.rail-node__io strong {
  font-family: var(--font-mono);
  font-size: 0.66rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-right: 0.3rem;
  color: var(--accent);
}

/* Pressure test cards */
.pt-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0.8rem;
}
.pt-card {
  padding: 1rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--bg);
  cursor: pointer;
  transition: all 180ms ease;
}
.pt-card:hover { border-color: var(--accent); background: var(--surface); }
.pt-card[open] { background: var(--surface); border-color: var(--accent); }
.pt-card summary {
  list-style: none;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  cursor: pointer;
}
.pt-card summary::-webkit-details-marker { display: none; }
.pt-card .pt-num {
  color: var(--accent);
  font-family: var(--font-display);
  font-size: 0.85rem;
  font-weight: 600;
  flex: 0 0 auto;
}
.pt-card .pt-name {
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 600;
  flex: 1;
}
.pt-card .pt-chev {
  color: var(--muted);
  font-size: 0.9rem;
  transition: transform 180ms ease;
}
.pt-card[open] .pt-chev { transform: rotate(90deg); }
.pt-card__body {
  margin-top: 0.8rem;
  padding-top: 0.8rem;
  border-top: 1px solid var(--border);
  display: grid;
  gap: 0.6rem;
}
.pt-card__row {
  display: grid;
  grid-template-columns: 5.5rem 1fr;
  gap: 0.6rem;
  font-size: 0.85rem;
  line-height: 1.5;
}
.pt-card__row strong {
  color: var(--warn);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding-top: 0.15rem;
}
.pt-card__row.audit strong { color: var(--accent); }
.pt-card__row.human strong { color: var(--muted); }
.pt-card__row p { margin: 0; color: var(--fg); }

/* Systems comparison */
.compare-wrap { overflow-x: auto; }
.compare {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
}
.compare th, .compare td {
  padding: 0.7rem 0.6rem;
  border-bottom: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}
.compare th {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.92rem;
  background: var(--bg);
  position: sticky;
  top: 0;
}
.compare th:first-child { min-width: 11rem; }
.compare th.us {
  background: var(--accent-soft);
  color: var(--accent-deep);
}
[data-theme="dark"] .compare th.us { color: var(--accent); }
.compare td:first-child {
  font-weight: 600;
  font-size: 0.82rem;
  color: var(--muted);
}
.compare td.us { background: var(--accent-soft); font-weight: 600; }
.compare .yes { color: var(--accent); }
.compare .no { color: var(--muted); }
.compare .partial { color: var(--warn); }

/* ============================================================
   Audit & limits
   ============================================================ */

.audit {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.2rem;
  margin-top: 2rem;
}
.audit__card {
  padding: 1.4rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--surface);
}
.audit__card h3 {
  margin: 0 0 0.4rem;
  font-family: var(--font-display);
  font-size: 1.05rem;
  font-weight: 600;
}
.audit__card .gate {
  display: inline-block;
  margin-bottom: 0.6rem;
  padding: 0.15rem 0.5rem;
  border: 1px solid var(--accent);
  border-radius: 4px;
  color: var(--accent);
  font-family: var(--font-mono);
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.04em;
}
.audit__card p {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
  line-height: 1.55;
}
.audit__card.limit .gate { border-color: var(--warn); color: var(--warn); }

.reading-list {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin-top: 2rem;
}
.paper {
  padding: 1rem 1.2rem;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface);
}
.paper h4 {
  margin: 0 0 0.3rem;
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 600;
}
.paper .paper-meta {
  display: block;
  margin-bottom: 0.4rem;
  color: var(--muted);
  font-size: 0.78rem;
  font-style: italic;
}
.paper p { margin: 0; color: var(--muted); font-size: 0.85rem; line-height: 1.5; }

/* ============================================================
   Footer
   ============================================================ */

.site-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: min(100%, var(--page-width));
  margin: 0 auto;
  padding: 2rem var(--gutter) 3rem;
  color: var(--muted);
  font-size: 0.78rem;
}
.site-footer p { margin: 0; }
.site-footer a {
  display: inline-flex;
  gap: 0.5rem;
  align-items: center;
  transition: color 180ms ease;
}
.site-footer a:hover { color: var(--accent); }
.site-footer a svg { width: 1rem; transition: transform 180ms ease; }
.site-footer a:hover svg { transform: translateY(-0.15rem); }

/* ============================================================
   Reveal animation
   ============================================================ */

.js .reveal {
  opacity: 0;
  transform: translateY(1.4rem);
  transition: opacity 600ms ease, transform 600ms cubic-bezier(0.22, 1, 0.36, 1);
}
.js .reveal.is-visible { opacity: 1; transform: translateY(0); }

@media (prefers-reduced-motion: reduce) {
  .js .reveal { opacity: 1; transform: none; transition: none; }
  html { scroll-behavior: auto; }
  .flow-line { animation: none; }
}

/* ============================================================
   Responsive
   ============================================================ */

@media (max-width: 900px) {
  .site-header__inner { grid-template-columns: 1fr auto; }
  .site-nav { display: none; }
  .hero__inner { grid-template-columns: 1fr; }
  .phases { grid-template-columns: 1fr; }
  .phases__col + .phases__col { border-left: 0; border-top: 1px solid var(--border); }
  .focus-grid { grid-template-columns: 1fr; }
  .pipeline { grid-template-columns: 1fr; }
  .flow-walkthrough { grid-template-columns: 1fr 1fr; }
  .stepper { grid-template-columns: 1fr; }
  .pt-grid { grid-template-columns: 1fr; }
  .audit { grid-template-columns: 1fr; }
  .reading-list { grid-template-columns: 1fr; }
  .section-heading { grid-template-columns: 1fr; gap: 1rem; }
  .section-heading h2 { max-width: none; }
  .decision__head { grid-template-columns: 2rem 1fr auto; }
  .decision__cat { display: none; }
}

@media (max-width: 680px) {
  :root { --gutter: 1.15rem; }
  .hero h1 { font-size: clamp(2.6rem, 9vw, 4.5rem); }
  .dive { padding: 1.2rem; }
}