.bd-article,
.bd-article * {
  box-sizing: border-box;
}
.bd-article {
  min-width: 0;
  overflow: clip;
  background:
    radial-gradient(circle at 12% 4%, rgba(45, 106, 231, 0.2), transparent 30rem),
    var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.68;
  /* Article-only spacing rhythm (paragraph / blank-line rules) */
  --bd-stack-gap: 1.25rem;
  --bd-stack-gap-lg: 2.5rem;
  --bd-rose: #ff6f91;
  --bd-rose-dim: rgba(255, 111, 145, 0.13);
  --bd-violet: #a77bf3;
  --bd-violet-dim: rgba(167, 123, 243, 0.13);
  --bd-green: #56c68b;
  --bd-green-dim: rgba(86, 198, 139, 0.12);
}

/* Shared multi-paragraph stack: one blank-line equivalent between blocks */
.bd-stack {
  display: flex;
  flex-direction: column;
  gap: var(--bd-stack-gap);
}

.bd-stack > * {
  margin-block: 0;
}

/* Extra blank line before a labeled callout or new beat */
.bd-stack-break {
  margin-top: calc(var(--bd-stack-gap-lg) - var(--bd-stack-gap));
}

.bd-article a {
  color: inherit;
}

.bd-article code,
.bd-article pre {
  font-family: var(--font-mono);
}

.bd-wrap {
  width: min(1200px, calc(100% - 3rem));
  margin-inline: auto;
}

/* Shared icon / brand plates */
.bd-article .sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.bd-mark {
  display: inline-grid;
  flex: 0 0 auto;
  width: 1.85rem;
  height: 1.85rem;
  place-items: center;
  place-content: center;
  border: 1px solid var(--color-border, rgba(152, 162, 179, 0.28));
  border-radius: 4px;
  background: var(--color-surface-2, rgba(255, 255, 255, 0.04));
  color: currentColor;
  line-height: 0;
  overflow: hidden;
  vertical-align: middle;
}

.bd-brand {
  display: block;
  width: 1em;
  height: 1em;
  object-fit: contain;
}

.bd-mark .bd-brand {
  width: 1.05rem;
  height: 1.05rem;
  margin: 0;
}

.bd-brand-pi {
  display: block;
  flex: 0 0 auto;
  color: currentColor;
}

.bd-glyph {
  display: block;
  flex: 0 0 auto;
  margin: 0;
  overflow: visible;
}

/* Lucide SVGs inside plates: force exact box so optical center is true */
.bd-mark > .bd-glyph,
.bd-mark > .bd-brand,
.bd-mark > svg {
  display: block;
  margin: 0 auto;
  flex: none;
}

.bd-model-chip {
  display: inline-flex !important;
  flex-direction: row !important;
  align-items: center;
  gap: 0.35rem;
  max-width: none;
  padding: 0.15rem 0.5rem 0.15rem 0.3rem;
  border: 1px solid color-mix(in srgb, currentColor 18%, transparent);
  border-radius: 999px;
  background: color-mix(in srgb, currentColor 7%, transparent);
  color: inherit;
  font: inherit;
  line-height: 1.2;
  vertical-align: middle;
  white-space: nowrap;
}

.bd-model-chip > .bd-brand,
.bd-model-chip > svg {
  display: block !important;
  flex: 0 0 auto !important;
  width: 0.95rem !important;
  height: 0.95rem !important;
  margin: 0 !important;
  color: currentColor;
}

.bd-model-chip > span:not(.sr-only) {
  display: inline !important;
  white-space: nowrap;
}

.bd-brief.is-dark .bd-model-chip {
  border-color: rgba(152, 162, 179, 0.28);
  background: rgba(255, 255, 255, 0.06);
  color: #f2f4f7;
}

.bd-brief.is-dark .bd-model-chip .bd-brand-pi,
.bd-brief.is-dark .bd-lineage-step .bd-brand-pi,
.bd-brief.is-dark .bd-mark .bd-brand-pi {
  color: #f2f4f7;
}

.bd-prose .bd-model-chip {
  border-color: color-mix(in srgb, var(--color-accent-soft, #2d6ae7) 28%, transparent);
  background: color-mix(in srgb, var(--color-accent-soft, #2d6ae7) 8%, transparent);
  color: var(--color-text);
  font-weight: 600;
  font-size: 0.92em;
}

.bd-brand-qwen,
.bd-brand-pi,
.bd-brand-openai {
  color: currentColor;
}

.bd-prose .bd-model-chip .bd-brand-pi,
.bd-prose .bd-model-chip .bd-brand-openai,
.bd-prose .bd-model-chip .bd-brand-qwen,
.bd-stat-mark .bd-brand-pi,
.bd-stat-mark .bd-brand-openai,
.bd-stat-mark .bd-brand-qwen,
.bd-table-value .bd-brand-pi,
.bd-table-value .bd-brand-openai,
.bd-table-value .bd-brand-qwen,
.bd-action-chain .bd-brand-pi,
.bd-action-chain .bd-brand-openai,
.bd-action-chain .bd-brand-qwen,
.bd-mark .bd-brand-pi,
.bd-mark .bd-brand-openai,
.bd-mark .bd-brand-qwen {
  color: currentColor;
}

/* Dark default: monochrome brand marks track text (white), not accent blue */
.bd-brief.is-dark .bd-brand-pi,
.bd-brief.is-dark .bd-brand-openai,
.bd-brief.is-dark .bd-brand-qwen,
.bd-hero .bd-brand-pi,
.bd-hero .bd-brand-openai,
.bd-hero .bd-brand-qwen {
  color: #f2f4f7;
}

.bd-prose .bd-mark .bd-brand-pi,
.bd-prose .bd-mark .bd-brand-openai,
.bd-prose .bd-mark .bd-brand-qwen,
.bd-prose .bd-model-chip .bd-brand-pi,
.bd-prose .bd-model-chip .bd-brand-openai,
.bd-prose .bd-model-chip .bd-brand-qwen {
  color: var(--color-text);
}

/* If a plate was tinted accent-blue, force icon/text to plate text color instead */
.bd-prose .bd-mark {
  color: var(--color-text);
  border-color: color-mix(in srgb, var(--color-text) 22%, transparent);
  background: color-mix(in srgb, var(--color-text) 8%, transparent);
}

.bd-prose .bd-table-value {
  color: var(--color-text);
}

.bd-prose .bd-table-value .bd-brand-qwen,
.bd-prose .bd-table-value .bd-brand-pi,
.bd-prose .bd-table-value .bd-brand-openai,
.bd-prose .bd-table-value .bd-glyph {
  color: var(--color-text);
}

.bd-skip {
  position: fixed;
  z-index: 100;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.65rem 0.9rem;
  border: 1px solid var(--color-accent);
  border-radius: 4px;
  background: var(--color-bg);
  color: var(--color-text);
  font: 600 0.75rem/1 var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  transform: translateY(-180%);
  transition: transform 140ms ease;
}

.bd-skip:focus {
  transform: translateY(0);
}

.bd-hero {
  position: relative;
  isolation: isolate;
  min-height: 720px;
  padding: clamp(6rem, 10vw, 9rem) 0 clamp(4rem, 7vw, 6rem);
  overflow: hidden;
  border-bottom: 1px solid var(--color-border);
  background:
    radial-gradient(circle at 76% 35%, rgba(45, 106, 231, 0.23), transparent 25rem),
    linear-gradient(135deg, #080c15 0%, #0c1423 52%, #111a2c 100%);
  color: #f2f4f7;
}

.bd-hero-grid {
  position: absolute;
  z-index: -2;
  inset: 0;
  opacity: 0.42;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 52px 52px;
  mask-image: linear-gradient(to bottom, black, transparent 94%);
}

.bd-orbit {
  position: absolute;
  z-index: -1;
  border: 1px solid rgba(45, 106, 231, 0.24);
  border-radius: 50%;
  pointer-events: none;
}

.bd-orbit::before,
.bd-orbit::after {
  content: "";
  position: absolute;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--color-accent);
  box-shadow: 0 0 24px rgba(45, 106, 231, 0.9);
}

.bd-orbit-one {
  top: 2rem;
  right: -11rem;
  width: 37rem;
  height: 37rem;
}

.bd-orbit-one::before {
  top: 15%;
  left: 15%;
}

.bd-orbit-one::after {
  right: -4px;
  top: 50%;
}

.bd-orbit-two {
  right: 2rem;
  bottom: -19rem;
  width: 31rem;
  height: 31rem;
  border-color: rgba(255, 111, 145, 0.16);
}

.bd-orbit-two::before {
  top: 8%;
  right: 23%;
  background: var(--bd-rose);
  box-shadow: 0 0 24px rgba(255, 111, 145, 0.72);
}

.bd-orbit-two::after {
  display: none;
}

.bd-hero-inner {
  position: relative;
}

.bd-hero-meta,
.bd-byline,
.bd-section-label,
.bd-film-heading > p {
  font-family: var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.12em;
}

.bd-hero-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: clamp(1.5rem, 3.5vw, 2.5rem);
  color: #98a2b3;
  font-size: 0.7rem;
}

.bd-section-label {
  margin: 0 0 1.2rem;
  color: var(--color-accent-soft);
  font-size: 0.72rem;
  font-weight: 700;
}

.bd-hero .bd-section-label {
  color: var(--bd-rose);
}

.bd-hero h1 {
  max-width: 960px;
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(3.2rem, 8vw, 7.9rem);
  font-weight: 500;
  letter-spacing: -0.055em;
  line-height: 0.92;
}

.bd-hero h1 em {
  display: block;
  color: var(--bd-rose);
  font-style: normal;
}

.bd-hero-deck {
  display: flex;
  flex-direction: column;
  gap: var(--bd-stack-gap);
  max-width: 52rem;
  margin: 2rem 0 0;
}

.bd-hero-deck p {
  margin: 0;
  color: #cbd2dc;
  font-size: clamp(1.05rem, 1.7vw, 1.28rem);
  line-height: 1.6;
}

.bd-hero-deck p:first-child {
  color: #e8ecf2;
  font-size: clamp(1.12rem, 1.9vw, 1.4rem);
  line-height: 1.55;
}

.bd-byline {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 2rem;
  color: #98a2b3;
  font-size: 0.7rem;
}

.bd-lineage {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0;
  margin: clamp(3rem, 6vw, 5rem) 0 0;
  padding: 0;
  list-style: none;
  border: 1px solid rgba(152, 162, 179, 0.2);
  border-radius: 4px;
  background: rgba(8, 12, 21, 0.7);
  backdrop-filter: blur(12px);
}

.bd-lineage li {
  position: relative;
  display: flex;
  align-items: center;
  gap: 0.9rem;
  min-height: 92px;
  padding: 1.2rem;
  border-right: 1px solid rgba(152, 162, 179, 0.16);
}

.bd-lineage li:last-child {
  border-right: 0;
}

.bd-lineage-step {
  display: grid;
  flex: 0 0 auto;
  width: 2.4rem;
  height: 2.4rem;
  place-items: center;
  border: 1px solid rgba(242, 244, 247, 0.55);
  border-radius: 4px;
  background: rgba(242, 244, 247, 0.06);
  color: #f2f4f7;
  font: 600 0.65rem/1 var(--font-mono);
  line-height: 0;
}

/* All lineage marks stay white (no per-tone color) */
.bd-lineage [data-tone] .bd-lineage-step,
.bd-lineage [data-tone="violet"] .bd-lineage-step,
.bd-lineage [data-tone="rose"] .bd-lineage-step,
.bd-lineage [data-tone="blue"] .bd-lineage-step,
.bd-lineage [data-tone="green"] .bd-lineage-step {
  border-color: rgba(242, 244, 247, 0.55);
  background: rgba(242, 244, 247, 0.06);
  color: #f2f4f7;
}

.bd-lineage-step .bd-brand-pi,
.bd-lineage-step .bd-brand-openai,
.bd-lineage-step .bd-brand-qwen,
.bd-lineage-step .bd-glyph {
  color: #f2f4f7;
}

.bd-lineage-step .bd-brand {
  width: 1.15rem;
  height: 1.15rem;
  color: #f2f4f7;
}

.bd-lineage-step .bd-glyph {
  width: 1rem;
  height: 1rem;
}

.bd-lineage small,
.bd-lineage strong {
  display: block;
}

.bd-lineage small {
  margin-bottom: 0.25rem;
  color: #98a2b3;
  font: 500 0.61rem/1.25 var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.bd-lineage strong {
  color: #f2f4f7;
  font-size: 0.86rem;
  line-height: 1.3;
}

.bd-lineage-arrow {
  position: absolute;
  z-index: 2;
  right: -0.63rem;
  display: grid;
  width: 1.25rem;
  height: 1.25rem;
  place-items: center;
  border-radius: 50%;
  background: #111a2c;
  color: #667085;
  font-size: 0.75rem;
}

.bd-intro-stack {
  border-bottom: 1px solid var(--color-border);
}

.bd-brief {
  scroll-margin-top: 110px;
  padding-block: clamp(4rem, 7vw, 6.5rem);
  border-bottom: 1px solid var(--color-border);
}

.bd-brief:last-child {
  border-bottom: 0;
}

.bd-brief.is-neutral {
  color-scheme: light;
  --color-bg: #ffffff;
  --color-surface: #ffffff;
  --color-surface-2: #f7f8fa;
  --color-surface-3: #f2f4f7;
  --color-text: #172033;
  --color-text-muted: #526079;
  --color-border: #d9e0eb;
  --color-accent-soft: #2159c9;
  --bd-rose: #c7315f;
  --bd-rose-dim: rgba(199, 49, 95, 0.09);
  background: var(--color-surface-2);
  color: var(--color-text);
}

.bd-brief.is-dark {
  border-color: rgba(152, 162, 179, 0.2);
  background:
    radial-gradient(circle at 82% 18%, rgba(45, 106, 231, 0.24), transparent 24rem),
    linear-gradient(120deg, #0b101b, #121d31);
  color: #f2f4f7;
}

/* PoC Setup is dense: full-width stack, not cramped two-column brief */
.bd-brief.is-dark .bd-brief-grid {
  grid-template-columns: 1fr;
  gap: 1.5rem;
}

.bd-brief.is-dark .bd-brief-heading h2 {
  max-width: 18ch;
}

.bd-brief.is-dark .bd-brief-copy {
  max-width: min(920px, 100%);
}

.bd-brief-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.78fr) minmax(0, 1.22fr);
  gap: clamp(3rem, 8vw, 8rem);
}

/* Intro 01: research stack, not poster slogan wall */
.bd-brief-stack {
  background:
    radial-gradient(circle at 12% 0%, rgba(45, 106, 231, 0.18), transparent 28rem),
    linear-gradient(180deg, #0a0f1a 0%, #0c111d 100%);
  color: #f2f4f7;
  border-bottom: 1px solid rgba(152, 162, 179, 0.2);
}

.bd-brief-stack-inner {
  max-width: min(820px, 100%);
  padding-block: clamp(3.5rem, 7vw, 5.5rem);
}

.bd-brief-stack .bd-section-label {
  margin: 0;
  color: #79a1f2;
}

.bd-brief-stack.bd-stack,
.bd-brief-stack .bd-stack {
  max-width: min(820px, 100%);
}

.bd-brief-stack h2 {
  max-width: 16ch;
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2.1rem, 4.2vw, 3.35rem);
  font-weight: 500;
  letter-spacing: -0.035em;
  line-height: 1.08;
  color: #f2f4f7;
}

.bd-brief-stack .bd-stack > p {
  max-width: 62ch;
  color: #c8d0dc;
  font-size: clamp(1.05rem, 1.8vw, 1.22rem);
  line-height: 1.6;
}

.bd-brief-stack .bd-stack > p code,
.bd-trigger-example code {
  color: #ff8eab;
  font-size: 0.92em;
}

.bd-trigger-example {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 0.45rem;
  max-width: 62ch;
  padding: 0.95rem 1.1rem;
  border: 1px solid rgba(152, 162, 179, 0.28);
  border-radius: 4px;
  background: rgba(8, 12, 21, 0.55);
}

.bd-trigger-example-label {
  color: #98a2b3;
  font: 700 0.68rem/1.35 var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.bd-trigger-example code {
  font-size: clamp(1rem, 1.6vw, 1.15rem);
  font-weight: 600;
  line-height: 1.4;
}

.bd-shot {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
  max-width: min(720px, 100%);
  margin: 0.25rem 0 0;
}

.bd-shot-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid rgba(152, 162, 179, 0.32);
  border-radius: 8px;
  background: #05070d;
  box-shadow:
    0 0 0 1px rgba(255, 255, 255, 0.03) inset,
    0 18px 48px rgba(0, 0, 0, 0.35);
}

.bd-shot-frame::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  box-shadow: inset 0 0 0 1px rgba(255, 171, 64, 0.08);
}

.bd-shot-frame img {
  display: block;
  width: 100%;
  height: auto;
  vertical-align: middle;
}

.bd-shot figcaption {
  max-width: 62ch;
  color: #aeb8c7;
  font-size: 0.9rem;
  line-height: 1.55;
}

.bd-shot figcaption code {
  color: #ff8eab;
  font-size: 0.9em;
}

.bd-brief-heading h2 {
  max-width: 540px;
  margin: 0;
  font-family: var(--font-display);
  font-size: clamp(2.55rem, 5vw, 4.7rem);
  font-weight: 500;
  letter-spacing: -0.045em;
  line-height: 1.02;
}

.bd-brief-copy {
  display: flex;
  flex-direction: column;
  gap: var(--bd-stack-gap);
  max-width: 700px;
}

.bd-brief-copy > p {
  margin: 0;
  color: var(--color-text-muted);
}

.bd-brief-copy .bd-brief-lede {
  color: var(--color-text);
  font-size: clamp(1.15rem, 2vw, 1.42rem);
  line-height: 1.62;
}

.bd-brief-copy > .bd-compact-list,
.bd-brief-copy > .bd-compare-list,
.bd-brief-copy > .bd-proof-list,
.bd-brief-copy > .bd-brief-proof,
.bd-brief-copy > .bd-brief-note,
.bd-brief-copy > .bd-stack {
  margin: 0;
}

.bd-brief-copy > .bd-stack.bd-stack-break {
  margin-top: calc(var(--bd-stack-gap-lg) - var(--bd-stack-gap));
}

.bd-brief.is-neutral .bd-brief-copy > .bd-stack > p {
  color: var(--color-text-muted);
}

.bd-brief-copy code {
  color: var(--bd-rose);
  font-size: 0.9em;
}

.bd-compact-list,
.bd-compare-list,
.bd-proof-list {
  margin: 2rem 0 0;
  padding: 0;
  list-style: none;
}

.bd-compact-list {
  border-top: 1px solid var(--color-border);
}

.bd-compact-list li {
  display: grid;
  grid-template-columns: minmax(8rem, 0.38fr) 1fr;
  gap: 1.5rem;
  padding: 1rem 0;
  border-bottom: 1px solid var(--color-border);
}

.bd-compact-list strong {
  display: inline-flex;
  flex-direction: row;
  align-items: center;
  gap: 0.55rem;
  color: var(--color-text);
  font: 700 0.68rem/1 var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.bd-compact-list strong .bd-mark {
  display: grid;
  flex: 0 0 1.55rem;
  width: 1.55rem;
  height: 1.55rem;
  place-items: center;
  place-content: center;
  border-color: color-mix(in srgb, var(--color-text) 28%, transparent);
  background: color-mix(in srgb, var(--color-text) 8%, transparent);
  color: var(--color-text);
}

.bd-compact-list strong .bd-mark .bd-glyph,
.bd-compact-list strong .bd-mark .bd-brand,
.bd-compact-list strong .bd-mark .bd-brand-pi,
.bd-compact-list strong .bd-mark .bd-brand-openai {
  width: 0.9rem !important;
  height: 0.9rem !important;
  color: var(--color-text);
}

/* OpenAI / Pi marks are monochrome and inherit text color (white on dark) */
.bd-brand-openai {
  color: currentColor;
}

.bd-compact-list span {
  color: var(--color-text);
  font-size: 0.9rem;
  line-height: 1.55;
}

.bd-compare-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: stretch;
  gap: 0.75rem;
}

.bd-compare-list > li {
  display: flex;
  flex-direction: column;
  height: 100%;
  min-height: 190px;
  padding: 1.4rem;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  background: var(--color-bg);
}

.bd-compare-kicker {
  display: flex;
  flex-direction: row;
  align-items: center;
  justify-content: flex-start;
  gap: 0.65rem;
  min-height: 1.85rem;
  color: var(--color-accent-soft);
  font: 700 0.66rem/1 var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.bd-compare-kicker > span {
  display: flex;
  align-items: center;
  margin: 0;
  padding: 0;
  line-height: 1;
  transform: translateY(0.5px); /* optical center with mono caps */
}

.bd-compare-kicker .bd-mark {
  display: grid;
  flex: 0 0 1.85rem;
  width: 1.85rem;
  height: 1.85rem;
  place-items: center;
  place-content: center;
  border-color: color-mix(in srgb, var(--color-accent-soft) 35%, transparent);
  background: color-mix(in srgb, var(--color-accent-soft) 10%, transparent);
  color: var(--color-accent-soft);
}

.bd-compare-kicker .bd-mark .bd-glyph {
  width: 1rem !important;
  height: 1rem !important;
  min-width: 1rem;
  min-height: 1rem;
}

.bd-compare-list > li > strong {
  display: block;
  margin-top: 1.25rem;
  color: var(--color-text);
  font: 500 1.25rem/1.22 var(--font-display);
}

.bd-compare-list > li > small {
  display: block;
  flex: 1 1 auto;
  margin-top: 0.85rem;
  color: var(--color-text-muted);
  font-size: 0.88rem;
  line-height: 1.55;
}

.bd-proof-list {
  display: grid !important;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  margin: 2rem 0 0;
  padding: 0;
  list-style: none !important;
  border-top: 1px solid rgba(152, 162, 179, 0.28);
}

.bd-proof-list > li {
  display: flex !important;
  flex-direction: row !important;
  align-items: center;
  gap: 0.9rem;
  min-height: 82px;
  min-width: 0;
  margin: 0;
  padding: 1rem 1.1rem 1rem 0;
  border-bottom: 1px solid rgba(152, 162, 179, 0.28);
  list-style: none !important;
}

.bd-proof-list > li:nth-child(odd) {
  border-right: 1px solid rgba(152, 162, 179, 0.28);
  padding-right: 1.1rem;
}

.bd-proof-list > li:nth-child(even) {
  padding-left: 1.1rem;
}

.bd-proof-index {
  display: grid !important;
  flex: 0 0 2.2rem;
  width: 2.2rem;
  height: 2.2rem;
  place-items: center;
  border: 1px solid rgba(242, 244, 247, 0.55);
  border-radius: 4px;
  background: rgba(242, 244, 247, 0.06);
  color: #f2f4f7;
  font: 700 0.65rem/1 var(--font-mono);
}

.bd-proof-body {
  display: flex !important;
  flex: 1 1 auto;
  flex-direction: row !important;
  align-items: center;
  gap: 0.75rem;
  min-width: 0;
}

.bd-proof-body .bd-mark {
  display: grid !important;
  flex: 0 0 2rem !important;
  width: 2rem !important;
  height: 2rem !important;
  max-width: 2rem;
  max-height: 2rem;
  margin: 0;
  place-items: center;
  place-content: center;
  border: 1px solid rgba(242, 244, 247, 0.35);
  border-radius: 4px;
  background: rgba(242, 244, 247, 0.08);
  color: #f2f4f7;
}

.bd-proof-body .bd-mark .bd-glyph,
.bd-proof-body .bd-mark .bd-brand,
.bd-proof-body .bd-mark svg {
  display: block !important;
  width: 1.05rem !important;
  height: 1.05rem !important;
  margin: 0 !important;
  color: #f2f4f7;
  stroke: #f2f4f7;
}

.bd-proof-body strong {
  display: block !important;
  flex: 1 1 auto;
  min-width: 0;
  color: #f2f4f7;
  font-size: 0.88rem;
  font-weight: 600;
  line-height: 1.35;
}

.bd-proof-list strong {
  color: #f2f4f7;
  font-size: 0.88rem;
  font-weight: 600;
  line-height: 1.45;
}

.bd-brief.is-dark .bd-brief-lede {
  display: block;
}

.bd-brief.is-dark .bd-brief-lede .bd-model-chip {
  display: inline-flex !important;
  margin: 0 0.15rem;
  vertical-align: middle;
}

.bd-brief.is-dark .bd-section-label {
  color: #79a1f2;
}

.bd-brief.is-dark .bd-brief-lede,
.bd-brief.is-dark .bd-brief-heading h2 {
  color: #f2f4f7;
}

.bd-brief.is-dark .bd-brief-copy > p {
  color: #aeb8c7;
}

.bd-brief-note {
  font-size: 0.85rem;
}

.bd-film {
  padding-block: clamp(4rem, 8vw, 7rem);
}

.bd-film-heading {
  display: block;
  margin-bottom: 2rem;
}

.bd-film-heading h2,
.bd-section h2,
.bd-final h2,
.bd-sources h2 {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 500;
  letter-spacing: -0.035em;
  line-height: 1.05;
}

.bd-film-heading h2 {
  font-size: clamp(2.2rem, 5vw, 4.6rem);
}

.bd-film-heading > p {
  margin: 0 0 0.6rem;
  color: var(--color-text-muted);
  font-size: 0.65rem;
  text-align: right;
}

.bd-video-frame {
  position: relative;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: #080b12;
}

.bd-video-frame::before {
  content: "";
  position: absolute;
  z-index: 2;
  inset: 0;
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: inherit;
  pointer-events: none;
}

.bd-video-frame video {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  background: #080b12;
}

.bd-film-caption {
  max-width: 940px;
  margin: 1.25rem 0 0;
  padding-left: 1rem;
  border-left: 3px solid var(--bd-rose);
  color: var(--color-text-muted);
  font-size: 0.9rem;
  line-height: 1.65;
}

.bd-film-caption strong {
  color: var(--color-text);
}

.bd-film-caption code {
  color: var(--bd-rose);
}

.bd-film-transcript {
  margin-top: 1.25rem;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background: var(--color-surface);
}

.bd-film-transcript summary {
  padding: 1rem 1.15rem;
  color: var(--color-text);
  cursor: pointer;
  font: 600 0.72rem/1.4 var(--font-mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.bd-film-transcript summary:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: -4px;
}

.bd-film-transcript[open] summary {
  border-bottom: 1px solid var(--color-border);
}

.bd-film-transcript ol {
  margin: 0;
  padding: 0;
  list-style: none;
}

.bd-film-transcript li {
  display: grid;
  grid-template-columns: 7.5rem 1fr;
  gap: 1.25rem;
  padding: 1rem 1.15rem;
  border-bottom: 1px solid var(--color-border-soft);
}

.bd-film-transcript li:last-child {
  border-bottom: 0;
}

.bd-film-transcript time {
  color: var(--color-accent-soft);
  font: 600 0.68rem/1.5 var(--font-mono);
}

.bd-film-transcript strong {
  display: block;
  color: var(--color-text);
  font-size: 0.9rem;
}

.bd-film-transcript p {
  margin: 0.35rem 0 0;
  color: var(--color-text-muted);
  font-size: 0.84rem;
  line-height: 1.6;
}

.bd-stats {
  border-block: 1px solid var(--color-border);
  background: var(--color-surface);
}

.bd-stats .bd-wrap {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
}

.bd-stats .bd-wrap > div {
  display: flex;
  min-height: 140px;
  flex-direction: column;
  justify-content: center;
  padding: 2rem clamp(1rem, 3vw, 2.5rem);
  border-right: 1px solid var(--color-border);
}

.bd-stats .bd-wrap > div:first-child {
  padding-left: 0;
}

.bd-stats .bd-wrap > div:last-child {
  border-right: 0;
}

.bd-stat-mark {
  display: inline-grid;
  margin-bottom: 0.7rem;
  width: 2rem;
  height: 2rem;
  place-items: center;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  background: var(--color-surface-2, #f7f8fa);
  color: var(--color-text);
  line-height: 0;
}

.bd-stat-mark .bd-brand-pi,
.bd-stat-mark .bd-brand-openai,
.bd-stat-mark .bd-glyph {
  color: inherit;
}

.bd-stats strong {
  color: var(--color-accent-soft);
  font-family: var(--font-display);
  font-size: clamp(2.2rem, 4vw, 4rem);
  font-weight: 500;
  letter-spacing: -0.04em;
  line-height: 1;
}

.bd-stats .bd-wrap > div > span:not(.bd-stat-mark) {
  margin-top: 0.65rem;
  color: var(--color-text-muted);
  font: 500 0.7rem/1.4 var(--font-mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.bd-reading-layout {
  padding-block: clamp(3rem, 5vw, 5rem);
}

.bd-reading-layout .rk-content {
  min-width: 0;
}

.bd-prose {
  width: min(780px, 100%);
  margin-inline: auto;
}

.bd-section {
  scroll-margin-top: 110px;
}

.bd-section + .bd-section {
  margin-top: clamp(2.75rem, 4.5vw, 4rem);
  padding-top: clamp(2.25rem, 3.5vw, 3rem);
  border-top: 1px solid var(--color-border);
}

.bd-section h2,
.bd-final h2 {
  max-width: 760px;
  font-size: clamp(2.45rem, 5.5vw, 5.15rem);
}

.bd-section h3 {
  scroll-margin-top: 110px;
  margin: clamp(3.5rem, 6vw, 5rem) 0 1.1rem;
  font-family: var(--font-display);
  font-size: clamp(1.7rem, 3.2vw, 2.7rem);
  font-weight: 500;
  letter-spacing: -0.025em;
  line-height: 1.12;
}

.bd-section > p {
  margin: var(--bd-stack-gap) 0 0;
  color: var(--color-text-muted);
}

.bd-section > h2 + p,
.bd-section > .bd-section-label + h2 + p {
  margin-top: var(--bd-stack-gap);
}

.bd-section .bd-lede {
  color: var(--color-text);
  font-size: clamp(1.15rem, 2vw, 1.45rem);
  line-height: 1.65;
}

.bd-section > p + p {
  margin-top: var(--bd-stack-gap);
}

.bd-thesis,
.bd-warning {
  position: relative;
  margin: 2.5rem 0;
  padding: clamp(1.5rem, 4vw, 2.5rem);
  border: 1px solid var(--color-accent-line);
  border-radius: 4px;
  background:
    linear-gradient(135deg, var(--color-accent-dim), transparent 70%),
    var(--color-surface);
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 2.6vw, 2rem);
  font-weight: 500;
  letter-spacing: -0.02em;
  line-height: 1.35;
}

.bd-thesis span,
.bd-warning span {
  display: block;
  margin-bottom: 0.8rem;
  color: var(--color-accent-soft);
  font: 700 0.68rem/1 var(--font-mono);
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.bd-warning {
  border-color: rgba(255, 111, 145, 0.38);
  background:
    linear-gradient(135deg, var(--bd-rose-dim), transparent 70%),
    var(--color-surface);
}

.bd-warning span {
  color: var(--bd-rose);
}

.bd-warning ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.bd-warning li {
  position: relative;
  margin: 0;
  padding: 0.55rem 0 0.55rem 1.2rem;
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: clamp(1.1rem, 2.1vw, 1.45rem);
  font-weight: 500;
  letter-spacing: -0.015em;
  line-height: 1.4;
}

.bd-warning li + li {
  border-top: 1px solid color-mix(in srgb, var(--bd-rose) 18%, transparent);
}

.bd-warning li::before {
  content: "";
  position: absolute;
  top: 1.05rem;
  left: 0;
  width: 0.4rem;
  height: 0.4rem;
  border-radius: 50%;
  background: var(--bd-rose);
}

.bd-code {
  margin: 2.5rem 0;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: #080b12;
  color: #d9e2ef;
}

.bd-code-head {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.85rem 1rem;
  border-bottom: 1px solid rgba(152, 162, 179, 0.16);
  background: #0d1420;
}

.bd-code-head span {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #667085;
}

.bd-code-head span:nth-child(1) { background: var(--bd-rose); }
.bd-code-head span:nth-child(2) { background: #d9a441; }
.bd-code-head span:nth-child(3) { background: var(--bd-green); }

.bd-code-head b {
  margin-left: auto;
  color: #667085;
  font: 500 0.65rem/1 var(--font-mono);
  letter-spacing: 0.06em;
}

.bd-code pre {
  margin: 0;
  padding: clamp(1.25rem, 3vw, 2rem);
  overflow-x: auto;
  color: #d9e2ef;
  font-size: clamp(0.8rem, 1.6vw, 1rem);
  line-height: 1.8;
}

.bd-risk-grid,
.bd-control-grid {
  display: grid;
  gap: 0.75rem;
  margin-top: 2rem;
  align-items: stretch;
}

.bd-risk-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

/* Shared equal-height cards (risk + controls) */
.bd-card {
  display: flex;
  flex-direction: column;
  align-items: stretch;
  height: 100%;
  min-height: 100%;
  min-width: 0;
  overflow: hidden;
  padding: 1.35rem 1.4rem 1.45rem;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  background: var(--color-surface);
}

.bd-card.is-active {
  border-color: rgba(255, 111, 145, 0.4);
  background:
    linear-gradient(145deg, var(--bd-rose-dim), transparent 72%),
    var(--color-surface);
}

.bd-card-index {
  display: block;
  flex: 0 0 auto;
  margin: 0;
  color: #f2f4f7;
  font: 700 0.66rem/1 var(--font-mono);
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.bd-card.is-active .bd-card-index {
  color: #f2f4f7;
}

/* Beat .bd-section h3 huge display sizing */
.bd-section h3.bd-card-title,
.bd-card-title {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 0.65rem;
  margin: 1.15rem 0 0;
  min-width: 0;
  color: var(--color-text);
  font-family: var(--font-display);
  font-size: 1.2rem !important;
  font-weight: 500;
  letter-spacing: -0.02em;
  line-height: 1.25 !important;
}

.bd-card-title > span {
  display: block;
  flex: 1 1 auto;
  min-width: 0;
  overflow-wrap: anywhere;
  line-height: 1.25;
}

.bd-card-title .bd-mark {
  display: grid;
  flex: 0 0 1.85rem;
  align-self: center;
  width: 1.85rem !important;
  height: 1.85rem !important;
  max-width: 1.85rem;
  max-height: 1.85rem;
  margin: 0;
  place-items: center;
  place-content: center;
  border: 1px solid rgba(242, 244, 247, 0.55);
  background: rgba(242, 244, 247, 0.06);
  color: #f2f4f7;
}

.bd-card-title .bd-mark .bd-glyph,
.bd-card-title .bd-mark .bd-brand,
.bd-card-title .bd-mark svg {
  width: 1rem !important;
  height: 1rem !important;
  color: #f2f4f7;
  stroke: #f2f4f7;
}

/* Active card: keep outer rose rim, but icon plate stays white */
.bd-card.is-active .bd-card-title .bd-mark {
  border-color: rgba(242, 244, 247, 0.55);
  background: rgba(242, 244, 247, 0.06);
  color: #f2f4f7;
}

/* Control + risk grids: force white chrome (override any accent leftovers) */
.bd-control-grid .bd-card-index,
.bd-risk-grid .bd-card-index,
.bd-control-grid .bd-card-title .bd-mark,
.bd-risk-grid .bd-card-title .bd-mark,
.bd-control-grid .bd-card-title .bd-mark .bd-glyph,
.bd-risk-grid .bd-card-title .bd-mark .bd-glyph,
.bd-control-grid .bd-card-title .bd-mark svg,
.bd-risk-grid .bd-card-title .bd-mark svg {
  color: #f2f4f7;
  stroke: #f2f4f7;
}

.bd-control-grid .bd-card-title .bd-mark,
.bd-risk-grid .bd-card-title .bd-mark {
  border-color: rgba(242, 244, 247, 0.55);
  background: rgba(242, 244, 247, 0.06);
}

.bd-card > p {
  flex: 1 1 auto;
  margin: 0.75rem 0 0;
  color: var(--color-text-muted);
  font-size: 0.84rem;
  line-height: 1.55;
}

.bd-card-points {
  flex: 1 1 auto;
  margin: 0.85rem 0 0;
  padding: 0;
  list-style: none;
}

.bd-card-points li {
  position: relative;
  margin: 0;
  padding: 0.4rem 0 0.4rem 0.95rem;
  color: var(--color-text-muted);
  font-size: 0.84rem;
  line-height: 1.5;
}

.bd-card-points li + li {
  border-top: 1px solid color-mix(in srgb, var(--color-text) 10%, transparent);
}

.bd-card-points li::before {
  content: "";
  position: absolute;
  top: 0.85rem;
  left: 0;
  width: 0.35rem;
  height: 0.35rem;
  border-radius: 50%;
  background: color-mix(in srgb, var(--color-text) 55%, transparent);
}



.bd-action-chain {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0;
  margin: 2rem 0 0;
  padding: 0;
  list-style: none;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  background: var(--color-surface);
}

.bd-action-chain li {
  position: relative;
  min-height: 230px;
  padding: 1.4rem;
  border-right: 1px solid var(--color-border);
}

.bd-action-chain li:last-child {
  border-right: 0;
}

.bd-chain-index {
  color: var(--color-text-muted);
  font: 600 0.7rem/1 var(--font-mono);
}

.bd-action-chain .bd-mark {
  display: grid;
  margin-top: 1.15rem;
  width: 2.2rem;
  height: 2.2rem;
  place-items: center;
  place-content: center;
  border-color: color-mix(in srgb, var(--color-text) 22%, transparent);
  background: color-mix(in srgb, var(--color-text) 8%, transparent);
  color: var(--color-text);
}

.bd-action-chain .bd-mark .bd-glyph,
.bd-action-chain .bd-mark .bd-brand {
  color: var(--color-text);
}

.bd-action-chain small,
.bd-action-chain strong {
  display: block;
}

.bd-action-chain small {
  margin-top: 0.85rem;
  color: var(--color-text-muted);
  font: 600 0.65rem/1 var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.bd-action-chain strong {
  margin-top: 0.5rem;
  font-family: var(--font-display);
  font-size: 1.25rem;
  font-weight: 500;
}

.bd-table-value {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  min-width: 0;
  color: var(--color-text);
}

.bd-table-value .bd-brand,
.bd-table-value .bd-glyph {
  flex: 0 0 auto;
  color: var(--color-text);
}

.bd-table-value .bd-brand {
  width: 1rem;
  height: 1rem;
}

.bd-table-value code {
  color: inherit;
}

.bd-action-chain p {
  margin: 0.8rem 0 0;
  color: var(--color-text-muted);
  font-size: 0.78rem;
  line-height: 1.5;
}

.bd-table-wrap {
  margin: 2.5rem 0;
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: 4px;
}

.bd-table-wrap:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

.bd-table-wrap table {
  width: 100%;
  min-width: 620px;
  border-collapse: collapse;
  background: var(--color-surface);
}

.bd-table-wrap caption {
  padding: 1rem 1.25rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font: 600 0.68rem/1.4 var(--font-mono);
  letter-spacing: 0.08em;
  text-align: left;
  text-transform: uppercase;
}

.bd-table-wrap th,
.bd-table-wrap td {
  padding: 0.95rem 1.25rem;
  border-bottom: 1px solid var(--color-border-soft);
  text-align: left;
  vertical-align: top;
}

.bd-table-wrap tr:last-child th,
.bd-table-wrap tr:last-child td {
  border-bottom: 0;
}

.bd-table-wrap th {
  width: 34%;
  color: var(--color-text-muted);
  font-size: 0.8rem;
  font-weight: 500;
}

.bd-table-wrap td {
  color: var(--color-text);
}

.bd-table-wrap code {
  font-size: 0.77rem;
  white-space: normal;
}

.bd-trace {
  display: grid;
  justify-items: start;
  gap: 0.45rem;
  margin: 1.5rem 0 2.5rem;
  padding: 1.5rem;
  border-left: 3px solid var(--color-accent);
  background: var(--color-surface);
}

.bd-trace code {
  color: var(--color-text);
  font-size: 0.78rem;
}

.bd-trace span {
  padding-left: 0.35rem;
  color: var(--color-accent-soft);
}

.bd-split-proof {
  display: grid;
  grid-template-columns: 1fr 1fr;
  margin: 2.5rem 0;
  overflow: hidden;
  border: 1px solid var(--color-border);
  border-radius: 4px;
  background: var(--color-surface);
}

.bd-split-pane {
  display: flex;
  flex-direction: column;
  min-height: 0;
  min-width: 0;
  padding: 1.25rem 1.35rem 1.15rem;
  background: var(--color-surface);
}

.bd-split-pane + .bd-split-pane,
.bd-split-pane.is-trigger {
  border-left: 1px solid rgba(255, 111, 145, 0.36);
  background:
    linear-gradient(135deg, var(--bd-rose-dim), transparent 75%),
    var(--color-surface);
}

.bd-split-head {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  margin: 0 0 1rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--color-border);
}

.bd-split-head span {
  color: var(--color-text-muted);
  font: 700 0.68rem/1.2 var(--font-mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.bd-split-pane.is-trigger .bd-split-head span {
  color: var(--bd-rose);
}

.bd-split-head small {
  color: var(--color-text-muted);
  font: 500 0.72rem/1.35 var(--font-mono);
  letter-spacing: 0.02em;
  opacity: 0.9;
}

.bd-transcript {
  display: flex;
  flex: 1 1 auto;
  flex-direction: column;
  gap: 0.65rem;
  min-width: 0;
}

.bd-turn {
  display: grid;
  grid-template-columns: 5.75rem minmax(0, 1fr);
  gap: 0.65rem;
  align-items: start;
}

.bd-turn-role {
  margin-top: 0.15rem;
  color: var(--color-text-muted);
  font: 700 0.62rem/1.3 var(--font-mono);
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.bd-turn-user .bd-turn-role {
  color: #79a1f2;
}

.bd-turn-model .bd-turn-role {
  color: #56c68b;
}

.bd-turn-tool .bd-turn-role,
.bd-turn-system .bd-turn-role {
  color: var(--bd-rose);
}

.bd-turn-text {
  margin: 0;
  color: var(--color-text);
  font-size: 0.9rem;
  line-height: 1.45;
  word-break: break-word;
}

.bd-turn.is-tool .bd-turn-text,
.bd-turn-tool .bd-turn-text,
.bd-turn-system .bd-turn-text {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  line-height: 1.45;
}

.bd-turn-text code {
  display: inline-block;
  max-width: 100%;
  padding: 0.35rem 0.5rem;
  border: 1px solid color-mix(in srgb, var(--color-text) 14%, transparent);
  border-radius: 4px;
  background: color-mix(in srgb, var(--color-text) 6%, transparent);
  color: var(--color-text);
  font: 0.78rem/1.4 var(--font-mono);
  word-break: break-all;
}

.bd-split-foot {
  margin: 1rem 0 0;
  padding-top: 0.85rem;
  border-top: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: 0.8rem;
  line-height: 1.45;
}

.bd-control-grid {
  grid-template-columns: 1fr 1fr;
  margin: 2.5rem 0;
}

.bd-control-grid .bd-card {
  min-height: 250px;
}

.bd-limitations {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  margin: 2rem 0;
  padding: 0;
  border-top: 1px solid var(--color-border);
  list-style: none;
}

.bd-limitations li {
  position: relative;
  padding: 1.1rem 1rem 1.1rem 2rem;
  border-bottom: 1px solid var(--color-border);
  color: var(--color-text-muted);
  font-size: 0.86rem;
}

.bd-limitations li:nth-child(odd) {
  border-right: 1px solid var(--color-border);
}

.bd-limitations li::before {
  content: "";
  position: absolute;
  top: 1.55rem;
  left: 0.65rem;
  width: 6px;
  height: 6px;
  border: 1px solid var(--bd-rose);
  border-radius: 50%;
}

.bd-final {
  margin-top: clamp(3rem, 7vw, 5rem);
  padding: clamp(2rem, 5vw, 4rem);
  border: 1px solid var(--color-accent-line);
  border-radius: 4px;
  background:
    radial-gradient(circle at 90% 10%, rgba(45, 106, 231, 0.23), transparent 18rem),
    #0b1322;
  color: #f2f4f7;
}

.bd-final > span {
  display: block;
  margin-bottom: 1.25rem;
  color: #79a1f2;
  font: 700 0.7rem/1 var(--font-mono);
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.bd-final h2 {
  color: #f2f4f7;
}

.bd-final p {
  max-width: 650px;
  margin: 1.5rem 0 0;
  color: #aeb8c7;
}

.bd-article .rk-cite a {
  color: var(--color-accent-soft);
}

.bd-article .rk-sources {
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
}

.bd-article .rk-sources > .wrap {
  width: min(1200px, calc(100% - 3rem));
  max-width: none;
  margin-inline: auto;
  padding-block: clamp(5rem, 9vw, 8rem);
}

.bd-article .rk-sources .section-head {
  max-width: 760px;
  margin-bottom: 2.5rem;
}

.bd-article .rk-sources .section-kicker {
  margin-bottom: 1rem;
  color: var(--color-accent-soft);
  font: 700 0.7rem/1 var(--font-mono);
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

.bd-article .rk-sources .section-head h2 {
  margin: 0;
  color: var(--color-text);
  font: 500 clamp(2.4rem, 5vw, 4.8rem)/1.05 var(--font-display);
  letter-spacing: -0.04em;
}

.bd-article .rk-sources .section-head p {
  margin: 1.25rem 0 0;
  color: var(--color-text-muted);
}

.bd-article a:focus-visible,
.bd-article button:focus-visible,
.bd-article video:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 4px;
}

@media (max-width: 1079px) {
  .bd-reading-layout {
    width: min(820px, calc(100% - 3rem));
    margin-inline: auto;
  }
}

@media (max-width: 900px) {
  .bd-lineage {
    grid-template-columns: 1fr 1fr;
  }

  .bd-lineage li:nth-child(2) {
    border-right: 0;
  }

  .bd-lineage li:nth-child(-n + 2) {
    border-bottom: 1px solid rgba(152, 162, 179, 0.16);
  }

  .bd-lineage li:nth-child(3) {
    border-right: 1px solid rgba(152, 162, 179, 0.16);
  }

  .bd-lineage li:nth-child(2) .bd-lineage-arrow {
    display: none;
  }

  .bd-action-chain {
    grid-template-columns: 1fr 1fr;
  }

  .bd-action-chain li:nth-child(2) {
    border-right: 0;
  }

  .bd-action-chain li:nth-child(-n + 2) {
    border-bottom: 1px solid var(--color-border);
  }
}

@media (max-width: 760px) {
  .bd-wrap,
  .bd-reading-layout,
  .bd-article .rk-sources > .wrap {
    width: min(100% - 2rem, 720px);
  }

  .bd-hero {
    min-height: auto;
    padding-top: 5rem;
  }

  .bd-hero-meta {
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 3.5rem;
  }

  .bd-hero-meta span:last-child {
    text-align: right;
  }

  .bd-hero h1 {
    font-size: clamp(3rem, 16vw, 5.1rem);
  }

  .bd-hero-deck {
    font-size: 1.05rem;
  }

  .bd-brief-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }

  .bd-brief-heading h2 {
    font-size: clamp(2.6rem, 13vw, 4.2rem);
  }

  .bd-compact-list li {
    grid-template-columns: 1fr;
    gap: 0.35rem;
  }

  .bd-compare-list,
  .bd-proof-list {
    grid-template-columns: 1fr;
  }

  .bd-compare-list li {
    min-height: 0;
  }

  .bd-proof-list > li,
  .bd-proof-list > li:nth-child(even) {
    padding-inline: 0;
    border-right: 0;
  }

  .bd-proof-list > li:nth-child(odd) {
    border-right: 0;
    padding-right: 0;
  }

  .bd-lineage {
    grid-template-columns: 1fr;
  }

  .bd-lineage li,
  .bd-lineage li:nth-child(3) {
    min-height: 82px;
    border-right: 0;
    border-bottom: 1px solid rgba(152, 162, 179, 0.16);
  }

  .bd-lineage li:last-child {
    border-bottom: 0;
  }

  .bd-lineage-arrow {
    display: none;
  }

  .bd-film-heading {
    display: block;
  }

  .bd-film-heading > p {
    margin-top: 1rem;
    text-align: left;
  }

  .bd-film-caption {
    font-size: 0.82rem;
  }

  .bd-film-transcript li {
    grid-template-columns: 1fr;
    gap: 0.35rem;
  }

  .bd-stats .bd-wrap {
    grid-template-columns: 1fr;
  }

  .bd-stats .bd-wrap > div,
  .bd-stats .bd-wrap > div:first-child {
    min-height: 110px;
    padding-inline: 0;
    border-right: 0;
    border-bottom: 1px solid var(--color-border);
  }

  .bd-stats .bd-wrap > div:last-child {
    border-bottom: 0;
  }

  .bd-section h2,
  .bd-final h2 {
    font-size: clamp(2.25rem, 12vw, 3.6rem);
  }

  .bd-risk-grid,
  .bd-control-grid,
  .bd-split-proof,
  .bd-limitations {
    grid-template-columns: 1fr;
  }

  .bd-split-pane + .bd-split-pane,
  .bd-split-pane.is-trigger {
    border-top: 1px solid rgba(255, 111, 145, 0.36);
    border-left: 0;
  }

  .bd-limitations li:nth-child(odd) {
    border-right: 0;
  }

  .bd-control-grid .bd-card,
  .bd-risk-grid .bd-card {
    min-height: 0;
  }
}

@media (max-width: 520px) {
  .bd-action-chain {
    grid-template-columns: 1fr;
  }

  .bd-action-chain li,
  .bd-action-chain li:nth-child(2) {
    min-height: auto;
    border-right: 0;
    border-bottom: 1px solid var(--color-border);
  }

  .bd-action-chain li:last-child {
    border-bottom: 0;
  }

  .bd-action-chain small {
    margin-top: 1rem;
  }
}

@media (prefers-color-scheme: light) {
  .bd-article {
    --bd-rose: #c7315f;
    --bd-rose-dim: rgba(199, 49, 95, 0.09);
    --bd-violet: #734bb5;
    --bd-violet-dim: rgba(115, 75, 181, 0.09);
    --bd-green: #277b50;
    --bd-green-dim: rgba(39, 123, 80, 0.09);
  }
}

@media (prefers-reduced-motion: reduce) {
  .bd-article *,
  .bd-article *::before,
  .bd-article *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}