/* ============================================================
   RAI Brain — Physical AI Stack
   Layered interactive framework. Dark theme, layer-tinted.
   Extends site.css tokens (--bg, --ink, --rai-grad, etc).
   ============================================================ */

/* Layer accent tokens — applied via [data-layer="..."] on a scope element. */
:root {
  --pas-blue:    #5aa1ff;
  --pas-cyan:    #4ad8ee;
  --pas-green:   #46d39a;
  --pas-purple:  #b48cff;
  --pas-orange:  #ff9a5a;

  --pas-blue-soft:    rgba(90, 161, 255, 0.18);
  --pas-cyan-soft:    rgba(74, 216, 238, 0.18);
  --pas-green-soft:   rgba(70, 211, 154, 0.18);
  --pas-purple-soft:  rgba(180, 140, 255, 0.18);
  --pas-orange-soft:  rgba(255, 154, 90, 0.18);

  --pas-card-bg:      #0c0e14;
  --pas-card-bg-2:    #10131b;
  --pas-card-line:    rgba(255, 255, 255, 0.10);
  --pas-card-line-2:  rgba(255, 255, 255, 0.18);
  --pas-radius:       14px;
  --pas-radius-sm:    8px;
}

[data-layer="embodiment"]    { --pas-accent: var(--pas-blue);   --pas-accent-soft: var(--pas-blue-soft); }
[data-layer="perception"]    { --pas-accent: var(--pas-cyan);   --pas-accent-soft: var(--pas-cyan-soft); }
[data-layer="cognition"]     { --pas-accent: var(--pas-green);  --pas-accent-soft: var(--pas-green-soft); }
[data-layer="action"]        { --pas-accent: var(--pas-purple); --pas-accent-soft: var(--pas-purple-soft); }
[data-layer="learning"]      { --pas-accent: var(--pas-orange); --pas-accent-soft: var(--pas-orange-soft); }

/* ============================================================
   Page scaffolding (extends .page-head from site.css)
   ============================================================ */
.pas-page {
  --pas-accent: var(--rai-grad);
  --pas-accent-soft: rgba(197, 146, 235, 0.18);
}

.pas-breadcrumb {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 28px;
}
.pas-breadcrumb a {
  color: var(--ink-2);
  border-bottom: 1px solid transparent;
  transition: color var(--t-fast) var(--ease), border-color var(--t-fast) var(--ease);
}
.pas-breadcrumb a:hover {
  color: var(--ink-0);
  border-bottom-color: var(--line-hot);
}
.pas-breadcrumb .pas-sep { color: var(--ink-5); }
.pas-breadcrumb .pas-current { color: var(--ink-0); }

/* Title block on detail pages */
.pas-titleblock {
  display: grid;
  gap: 14px;
  margin-bottom: 48px;
}
.pas-titleblock__num {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--pas-accent, var(--ink-3));
  display: inline-flex;
  align-items: center;
  gap: 12px;
}
.pas-titleblock__num::before {
  content: "";
  width: 32px; height: 1px;
  background: currentColor;
}
.pas-titleblock h1 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(40px, 6vw, 88px);
  letter-spacing: -0.04em;
  line-height: 0.98;
  color: var(--ink-0);
  margin: 0;
}
.pas-titleblock h1 em {
  font-style: normal;
  color: var(--pas-accent, var(--ink-0));
}
.pas-titleblock__sub {
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(20px, 2.2vw, 28px);
  line-height: 1.35;
  color: var(--ink-1);
  margin: 0;
  max-width: 50ch;
}
.pas-titleblock__def {
  font-size: 17px;
  line-height: 1.6;
  color: var(--ink-2);
  margin: 12px 0 0;
  max-width: 64ch;
}

/* ============================================================
   Key idea + takeaway boxes
   ============================================================ */
.key-idea-box,
.takeaway-box {
  position: relative;
  border-radius: var(--pas-radius);
  padding: clamp(28px, 4vw, 44px);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-card-line-2), var(--pas-card-line-2)) border-box;
  border: 1.5px solid transparent;
  overflow: hidden;
  isolation: isolate;
}
.key-idea-box::before,
.takeaway-box::before {
  content: "";
  position: absolute; inset: 0;
  background:
    radial-gradient(700px 360px at 100% 0%, var(--pas-accent-soft, rgba(197,146,235,0.12)), transparent 60%);
  pointer-events: none;
  z-index: -1;
}
.key-idea-box__label,
.takeaway-box__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--pas-accent, var(--ink-3));
  margin-bottom: 18px;
  display: inline-flex; align-items: center; gap: 12px;
}
.key-idea-box__label::before,
.takeaway-box__label::before {
  content: "";
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--pas-accent, var(--ink-0));
  box-shadow: 0 0 18px var(--pas-accent, transparent);
}
.key-idea-box p,
.takeaway-box p {
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(20px, 2.2vw, 28px);
  line-height: 1.35;
  color: var(--ink-0);
  margin: 0 0 12px;
  max-width: 56ch;
}
.takeaway-box p strong {
  font-weight: 700;
  color: var(--pas-accent, var(--ink-0));
}

/* ============================================================
   Layer cards — used on overview page
   ============================================================ */
.layer-cards {
  display: grid;
  gap: 18px;
  grid-template-columns: 1fr;
}
@media (min-width: 720px)  { .layer-cards { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1180px) { .layer-cards { grid-template-columns: repeat(5, 1fr); } }

.layer-card {
  position: relative;
  display: flex; flex-direction: column;
  text-align: left;
  width: 100%;
  padding: 28px 24px;
  border-radius: var(--pas-radius);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-card-line-2), var(--pas-card-line-2)) border-box;
  border: 1.5px solid transparent;
  color: inherit;
  cursor: pointer;
  isolation: isolate;
  overflow: hidden;
  transition:
    transform var(--t-med) var(--ease),
    box-shadow var(--t-med) var(--ease),
    background var(--t-fast) var(--ease);
}
.layer-card::before {
  content: "";
  position: absolute; inset: 0;
  background:
    radial-gradient(420px 240px at 0% 0%, var(--pas-accent-soft), transparent 65%);
  opacity: 0.85;
  pointer-events: none;
  z-index: -1;
}
.layer-card::after {
  content: "";
  position: absolute; left: 0; right: 0; top: 0;
  height: 2px;
  background: var(--pas-accent);
  opacity: 0.85;
}
.layer-card:hover,
.layer-card:focus-visible {
  transform: translateY(-4px);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-accent), var(--pas-accent)) border-box;
  box-shadow: 0 24px 60px -22px var(--pas-accent-soft), var(--glow-card);
  outline: none;
}
.layer-card__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.32em;
  text-transform: uppercase;
  color: var(--pas-accent);
  margin-bottom: 18px;
}
.layer-card__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 22px;
  letter-spacing: -0.02em;
  line-height: 1.1;
  color: var(--ink-0);
  margin: 0 0 8px;
}
.layer-card__tagline {
  font-size: 14px;
  color: var(--ink-2);
  line-height: 1.5;
  margin: 0 0 20px;
}
.layer-card__items {
  list-style: none;
  margin: 0 0 24px;
  padding: 0;
  display: grid;
  gap: 6px;
}
.layer-card__items li {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-2);
  padding-left: 14px;
  position: relative;
}
.layer-card__items li::before {
  content: "";
  position: absolute;
  left: 0; top: 0.55em;
  width: 6px; height: 1px;
  background: var(--pas-accent);
}
.layer-card__footer {
  margin-top: auto;
  padding-top: 16px;
  border-top: 1px solid var(--pas-card-line);
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-3);
}
.layer-card__footer .pas-arrow {
  width: 14px; height: 1px;
  background: var(--pas-accent);
  position: relative;
  transition: transform var(--t-fast) var(--ease);
}
.layer-card__footer .pas-arrow::after {
  content: "";
  position: absolute;
  right: -1px; top: -3px;
  width: 7px; height: 7px;
  border-right: 1px solid var(--pas-accent);
  border-top: 1px solid var(--pas-accent);
  transform: rotate(45deg);
}
.layer-card:hover .pas-arrow,
.layer-card:focus-visible .pas-arrow {
  transform: translateX(4px);
}

/* ============================================================
   Flow strip — chained pills, e.g. REAL WORLD → EMBODIMENT → ...
   ============================================================ */
.flow-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  align-items: center;
  padding: 20px 24px;
  border-radius: var(--pas-radius);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-card-line), var(--pas-card-line)) border-box;
  border: 1.5px solid transparent;
}
.flow-strip__node {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  padding: 8px 14px;
  border-radius: var(--r-sm);
  background: rgba(255,255,255,0.04);
  color: var(--ink-1);
  border: 1px solid var(--pas-card-line);
  white-space: nowrap;
}
.flow-strip__node--accent { color: var(--pas-accent); border-color: var(--pas-accent-soft); background: var(--pas-accent-soft); }
.flow-strip__node--embodiment { color: var(--pas-blue);   border-color: var(--pas-blue-soft);   background: var(--pas-blue-soft); }
.flow-strip__node--perception { color: var(--pas-cyan);   border-color: var(--pas-cyan-soft);   background: var(--pas-cyan-soft); }
.flow-strip__node--cognition  { color: var(--pas-green);  border-color: var(--pas-green-soft);  background: var(--pas-green-soft); }
.flow-strip__node--action     { color: var(--pas-purple); border-color: var(--pas-purple-soft); background: var(--pas-purple-soft); }
.flow-strip__node--learning   { color: var(--pas-orange); border-color: var(--pas-orange-soft); background: var(--pas-orange-soft); }
.flow-strip__arrow {
  width: 14px; height: 1px;
  background: var(--ink-3);
  position: relative;
  flex-shrink: 0;
}
.flow-strip__arrow::after {
  content: "";
  position: absolute;
  right: -1px; top: -3px;
  width: 7px; height: 7px;
  border-right: 1px solid var(--ink-3);
  border-top: 1px solid var(--ink-3);
  transform: rotate(45deg);
}

/* Infrastructure strip — special variant */
.infra-strip {
  margin-top: 24px;
  padding: 24px clamp(20px, 3vw, 32px);
  border-radius: var(--pas-radius);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-card-line-2), var(--pas-card-line-2)) border-box;
  border: 1.5px solid transparent;
  display: grid;
  gap: 16px;
}
.infra-strip__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--ink-3);
  display: inline-flex; align-items: center; gap: 12px;
}
.infra-strip__label strong {
  color: var(--ink-0);
  font-weight: 400;
  letter-spacing: 0.28em;
}
.infra-strip__items {
  display: flex; flex-wrap: wrap;
  gap: 10px;
}
.infra-strip__items button {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  padding: 8px 14px;
  border-radius: var(--r-sm);
  background: rgba(255,255,255,0.04);
  color: var(--ink-1);
  border: 1px solid var(--pas-card-line);
  cursor: pointer;
  transition: background var(--t-fast) var(--ease), border-color var(--t-fast) var(--ease), color var(--t-fast) var(--ease);
}
.infra-strip__items button:hover,
.infra-strip__items button:focus-visible {
  background: rgba(255,255,255,0.08);
  border-color: var(--line-hot);
  color: var(--ink-0);
  outline: none;
}

/* ============================================================
   Closed-loop footer line on overview
   ============================================================ */
.pas-closing {
  text-align: center;
  font-family: var(--font-display);
  font-weight: 300;
  font-size: clamp(18px, 1.9vw, 22px);
  color: var(--ink-2);
  letter-spacing: -0.005em;
  margin: 0;
  padding: 24px 0;
}
.pas-closing strong {
  font-weight: 700;
  color: var(--ink-0);
}

/* ============================================================
   Stack section — generic wrapper used inside detail pages
   ============================================================ */
.pas-stack { display: grid; gap: clamp(48px, 7vw, 80px); }
.pas-section { display: grid; gap: 24px; }
.pas-section__head {
  display: flex; align-items: baseline; justify-content: space-between;
  gap: 16px; flex-wrap: wrap;
}
.pas-section__head h2 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 3vw, 36px);
  letter-spacing: -0.025em;
  color: var(--ink-0);
  margin: 0;
}
.pas-section__head .pas-eyebrow {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--pas-accent, var(--ink-3));
}

/* ============================================================
   Capability cards — used on detail pages
   ============================================================ */
.cap-grid {
  display: grid;
  gap: 16px;
  grid-template-columns: 1fr;
}
@media (min-width: 720px)  { .cap-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1080px) { .cap-grid { grid-template-columns: repeat(3, 1fr); } }
.cap-grid--4 { grid-template-columns: 1fr; }
@media (min-width: 720px)  { .cap-grid--4 { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1080px) { .cap-grid--4 { grid-template-columns: repeat(4, 1fr); } }

.capability-card {
  text-align: left;
  width: 100%;
  padding: 24px;
  border-radius: var(--pas-radius);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-card-line), var(--pas-card-line)) border-box;
  border: 1.5px solid transparent;
  color: inherit;
  cursor: pointer;
  display: flex; flex-direction: column;
  gap: 12px;
  transition:
    transform var(--t-med) var(--ease),
    box-shadow var(--t-med) var(--ease),
    background var(--t-fast) var(--ease);
  position: relative;
  isolation: isolate;
  overflow: hidden;
}
.capability-card::before {
  content: "";
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 2px;
  background: var(--pas-accent);
  opacity: 0.65;
  transition: opacity var(--t-fast) var(--ease), width var(--t-fast) var(--ease);
}
.capability-card:hover,
.capability-card:focus-visible {
  transform: translateY(-2px);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-accent), var(--pas-accent)) border-box;
  box-shadow: 0 18px 44px -20px var(--pas-accent-soft);
  outline: none;
}
.capability-card:hover::before,
.capability-card:focus-visible::before {
  opacity: 1;
  width: 3px;
}
.capability-card__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 17px;
  letter-spacing: -0.015em;
  color: var(--ink-0);
  line-height: 1.2;
  margin: 0;
}
.capability-card__items {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid; gap: 6px;
}
.capability-card__items li {
  font-size: 13px;
  color: var(--ink-2);
  line-height: 1.5;
}
.capability-card__hint {
  margin-top: auto;
  padding-top: 12px;
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--ink-3);
  display: inline-flex; align-items: center; gap: 8px;
  opacity: 0;
  transition: opacity var(--t-fast) var(--ease), color var(--t-fast) var(--ease);
}
.capability-card:hover .capability-card__hint,
.capability-card:focus-visible .capability-card__hint {
  opacity: 1;
  color: var(--pas-accent);
}

/* Tooltip — small hover hint for any element with data-tip */
[data-tip] { position: relative; }
[data-tip]:hover::after,
[data-tip]:focus-visible::after {
  content: attr(data-tip);
  position: absolute;
  bottom: calc(100% + 8px);
  left: 50%;
  transform: translateX(-50%);
  background: var(--bg-3);
  color: var(--ink-0);
  border: 1px solid var(--pas-card-line-2);
  border-radius: var(--r-sm);
  padding: 8px 12px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  white-space: nowrap;
  z-index: 20;
  pointer-events: none;
}

/* ============================================================
   Pipeline / workflow chain
   ============================================================ */
.pipeline {
  display: grid;
  gap: 12px;
  grid-template-columns: 1fr;
  padding: 24px;
  border-radius: var(--pas-radius);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-card-line-2), var(--pas-card-line-2)) border-box;
  border: 1.5px solid transparent;
}
@media (min-width: 880px) {
  .pipeline {
    grid-template-columns: repeat(var(--pipeline-cols, 6), 1fr);
    gap: 8px;
    align-items: stretch;
  }
}
.pipeline__step {
  position: relative;
  padding: 16px;
  border-radius: var(--pas-radius-sm);
  background: rgba(255,255,255,0.04);
  border: 1px solid var(--pas-card-line);
  display: flex; flex-direction: column; gap: 6px;
  transition: border-color var(--t-fast) var(--ease), background var(--t-fast) var(--ease);
}
.pipeline__step:hover {
  border-color: var(--pas-accent);
  background: var(--pas-accent-soft);
}
.pipeline__step + .pipeline__step::before {
  content: "→";
  position: absolute;
  left: -14px; top: 50%;
  transform: translateY(-50%);
  color: var(--ink-3);
  font-family: var(--font-mono);
  font-size: 14px;
  display: none;
}
@media (min-width: 880px) {
  .pipeline__step + .pipeline__step::before { display: block; }
}
.pipeline__step-num {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--pas-accent);
}
.pipeline__step-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 14px;
  color: var(--ink-0);
  line-height: 1.25;
  margin: 0;
}
.pipeline__step-desc {
  font-size: 12px;
  color: var(--ink-2);
  line-height: 1.45;
  margin: 0;
}

/* ============================================================
   Three-column architecture (inputs | center | outputs)
   ============================================================ */
.arch-grid {
  display: grid;
  gap: 18px;
  grid-template-columns: 1fr;
}
@media (min-width: 960px) {
  .arch-grid { grid-template-columns: 1fr 1.4fr 1fr; gap: 24px; align-items: start; }
}
.arch-column { display: grid; gap: 16px; }
.arch-column__title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--pas-accent);
  margin: 0 0 4px;
}

/* Center body diagram on Embodiment page */
.body-diagram {
  position: relative;
  border-radius: var(--pas-radius);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-card-line-2), var(--pas-card-line-2)) border-box;
  border: 1.5px solid transparent;
  padding: 24px;
  display: grid; gap: 8px;
  min-height: 520px;
  overflow: hidden;
  isolation: isolate;
}
.body-diagram::before {
  content: "";
  position: absolute; inset: 0;
  background: radial-gradient(420px 320px at 50% 30%, var(--pas-accent-soft), transparent 65%);
  z-index: -1;
}
.body-diagram__title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--pas-accent);
  margin: 0;
}
.body-diagram__svg {
  display: block;
  width: 100%;
  height: auto;
  max-height: 420px;
  margin: 0 auto;
}
.body-diagram__svg .body-line {
  fill: none;
  stroke: var(--pas-accent);
  stroke-opacity: 0.6;
  stroke-width: 1;
  stroke-dasharray: 3 3;
  pointer-events: none;
}
.body-diagram__svg .body-shape {
  fill: rgba(255,255,255,0.03);
  stroke: var(--pas-card-line-2);
  stroke-width: 1;
  transition: fill var(--t-fast) var(--ease), stroke var(--t-fast) var(--ease);
}
.body-diagram__svg .body-shape--clickable {
  cursor: pointer;
}
.body-diagram__svg .body-shape--clickable:hover,
.body-diagram__svg .body-shape--clickable:focus-visible {
  fill: var(--pas-accent-soft);
  stroke: var(--pas-accent);
  outline: none;
}
.body-diagram__svg .body-shape--clickable:focus-visible {
  filter: drop-shadow(0 0 6px var(--pas-accent));
}
.body-diagram__svg .body-dot {
  fill: var(--pas-accent);
  stroke: var(--bg-1);
  stroke-width: 2;
  cursor: pointer;
  transition: r 180ms var(--ease), filter 180ms var(--ease);
}
.body-diagram__svg .body-dot:hover,
.body-diagram__svg .body-dot:focus-visible {
  r: 8;
  filter: drop-shadow(0 0 6px var(--pas-accent));
  outline: none;
}
.body-diagram__svg .body-label {
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  fill: var(--ink-1);
}
.body-callouts {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-top: 8px;
}
.body-callouts button {
  text-align: left;
  padding: 10px 12px;
  border-radius: var(--pas-radius-sm);
  background: rgba(255,255,255,0.03);
  border: 1px solid var(--pas-card-line);
  color: var(--ink-1);
  cursor: pointer;
  display: grid; gap: 4px;
  transition: border-color var(--t-fast) var(--ease), background var(--t-fast) var(--ease);
}
.body-callouts button:hover,
.body-callouts button:focus-visible {
  border-color: var(--pas-accent);
  background: var(--pas-accent-soft);
  outline: none;
}
.body-callouts__label {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--pas-accent);
}
.body-callouts__desc {
  font-size: 12px;
  color: var(--ink-2);
  line-height: 1.4;
}

/* ============================================================
   Trends and challenges rows
   ============================================================ */
.trend-grid {
  display: grid; gap: 12px;
  grid-template-columns: 1fr;
}
@media (min-width: 720px)  { .trend-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1080px) { .trend-grid { grid-template-columns: repeat(3, 1fr); } }

.trend-card {
  padding: 18px 20px;
  border-radius: var(--pas-radius-sm);
  background: rgba(255,255,255,0.03);
  border: 1px solid var(--pas-card-line);
  font-size: 14px;
  color: var(--ink-1);
  line-height: 1.5;
  display: flex; gap: 12px;
  transition: border-color var(--t-fast) var(--ease), background var(--t-fast) var(--ease), transform var(--t-fast) var(--ease);
}
.trend-card:hover {
  border-color: var(--pas-accent);
  background: var(--pas-accent-soft);
  transform: translateY(-1px);
}
.trend-card::before {
  content: "";
  flex-shrink: 0;
  width: 6px; height: 6px;
  margin-top: 7px;
  border-radius: 50%;
  background: var(--pas-accent);
  box-shadow: 0 0 12px var(--pas-accent);
}

.challenge-card::before {
  background: #ff7676;
  box-shadow: 0 0 12px rgba(255, 118, 118, 0.5);
}

/* ============================================================
   Role / enabler strip — labeled list of bullets
   ============================================================ */
.role-strip {
  padding: 28px;
  border-radius: var(--pas-radius);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-card-line), var(--pas-card-line)) border-box;
  border: 1.5px solid transparent;
}
.role-strip__title {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--pas-accent);
  margin: 0 0 18px;
}
.role-strip__items {
  display: grid;
  gap: 10px 24px;
  grid-template-columns: 1fr;
  list-style: none;
  margin: 0; padding: 0;
}
@media (min-width: 720px)  { .role-strip__items { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1080px) { .role-strip__items { grid-template-columns: repeat(3, 1fr); } }
.role-strip__items li {
  font-size: 14px;
  color: var(--ink-1);
  line-height: 1.5;
  padding-left: 16px;
  position: relative;
}
.role-strip__items li::before {
  content: "";
  position: absolute;
  left: 0; top: 0.6em;
  width: 8px; height: 1px;
  background: var(--pas-accent);
}

/* ============================================================
   Outputs strip
   ============================================================ */
.outputs-grid {
  display: grid;
  gap: 12px;
  grid-template-columns: 1fr;
}
@media (min-width: 720px)  { .outputs-grid { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 1080px) { .outputs-grid { grid-template-columns: repeat(5, 1fr); } }

.output-card {
  padding: 18px;
  border-radius: var(--pas-radius-sm);
  background: rgba(255,255,255,0.03);
  border: 1px solid var(--pas-card-line);
  border-left: 3px solid var(--pas-accent);
  display: grid; gap: 6px;
}
.output-card h4 {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--pas-accent);
  margin: 0;
}
.output-card p {
  font-size: 13px;
  color: var(--ink-2);
  line-height: 1.5;
  margin: 0;
  max-width: none;
}

/* ============================================================
   Loop diagram — central learning loop
   ============================================================ */
.loop-diagram {
  display: grid;
  gap: 16px;
  grid-template-columns: 1fr;
  padding: 32px;
  border-radius: var(--pas-radius);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-card-line-2), var(--pas-card-line-2)) border-box;
  border: 1.5px solid transparent;
  position: relative;
  isolation: isolate;
  overflow: hidden;
}
.loop-diagram::before {
  content: "";
  position: absolute; inset: 0;
  background: radial-gradient(520px 360px at 50% 50%, var(--pas-accent-soft), transparent 70%);
  z-index: -1;
}
@media (min-width: 880px) {
  .loop-diagram {
    grid-template-columns: repeat(3, 1fr);
    grid-template-rows: auto auto auto;
  }
  .loop-diagram__step:nth-child(1) { grid-column: 1; grid-row: 1; }
  .loop-diagram__step:nth-child(2) { grid-column: 2; grid-row: 1; }
  .loop-diagram__step:nth-child(3) { grid-column: 3; grid-row: 1; }
  .loop-diagram__core             { grid-column: 2; grid-row: 2; }
  .loop-diagram__step:nth-child(5) { grid-column: 3; grid-row: 3; }
  .loop-diagram__step:nth-child(6) { grid-column: 2; grid-row: 3; }
  .loop-diagram__step:nth-child(7) { grid-column: 1; grid-row: 3; }
}
.loop-diagram__step {
  padding: 18px;
  border-radius: var(--pas-radius-sm);
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--pas-card-line);
  cursor: pointer;
  display: grid; gap: 6px;
  transition: border-color var(--t-fast) var(--ease), background var(--t-fast) var(--ease), transform var(--t-fast) var(--ease);
}
.loop-diagram__step:hover {
  border-color: var(--pas-accent);
  background: var(--pas-accent-soft);
  transform: translateY(-2px);
}
.loop-diagram__num {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--pas-accent);
}
.loop-diagram__title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  color: var(--ink-0);
  line-height: 1.25;
  margin: 0;
}
.loop-diagram__desc {
  font-size: 12px;
  color: var(--ink-2);
  line-height: 1.45;
  margin: 0;
}
.loop-diagram__core {
  padding: 24px;
  border-radius: var(--pas-radius-sm);
  background: var(--pas-accent-soft);
  border: 1.5px solid var(--pas-accent);
  display: grid; gap: 8px;
  text-align: center;
  align-content: center;
}
.loop-diagram__core h4 {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  color: var(--ink-0);
  letter-spacing: -0.015em;
  margin: 0;
}
.loop-diagram__core p {
  font-size: 13px;
  color: var(--ink-1);
  margin: 0;
  max-width: none;
}

/* ============================================================
   Detail drawer
   ============================================================ */
.detail-drawer {
  position: fixed;
  top: 0; right: 0; bottom: 0;
  width: min(480px, 92vw);
  background: linear-gradient(180deg, #0a0c12, #06070a);
  border-left: 1px solid var(--pas-card-line-2);
  box-shadow: -20px 0 60px rgba(0, 0, 0, 0.6);
  transform: translateX(100%);
  transition: transform 320ms var(--ease);
  z-index: 100;
  display: flex; flex-direction: column;
  visibility: hidden;
}
.detail-drawer.is-open {
  transform: translateX(0);
  visibility: visible;
}
.detail-drawer__backdrop {
  position: fixed; inset: 0;
  background: rgba(6, 7, 10, 0.55);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  z-index: 99;
  opacity: 0;
  visibility: hidden;
  transition: opacity 240ms var(--ease);
}
.detail-drawer__backdrop.is-open {
  opacity: 1;
  visibility: visible;
}
.detail-drawer__header {
  display: flex; align-items: center; justify-content: space-between;
  gap: 12px;
  padding: 22px 28px;
  border-bottom: 1px solid var(--pas-card-line);
  position: relative;
}
.detail-drawer__header::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: -1px;
  height: 2px;
  background: var(--pas-accent, var(--ink-0));
  opacity: 0.85;
}
.detail-drawer__eyebrow {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--pas-accent, var(--ink-3));
}
.detail-drawer__close {
  width: 36px; height: 36px;
  display: inline-flex; align-items: center; justify-content: center;
  border-radius: 50%;
  background: rgba(255,255,255,0.05);
  border: 1px solid var(--pas-card-line);
  color: var(--ink-1);
  cursor: pointer;
  transition: background var(--t-fast) var(--ease), color var(--t-fast) var(--ease);
}
.detail-drawer__close:hover { background: rgba(255,255,255,0.1); color: var(--ink-0); }
.detail-drawer__close svg { width: 14px; height: 14px; }
.detail-drawer__body {
  flex: 1;
  overflow-y: auto;
  padding: 28px;
  display: grid; gap: 24px;
}
.detail-drawer__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: clamp(24px, 3vw, 32px);
  letter-spacing: -0.025em;
  color: var(--ink-0);
  margin: 0;
  line-height: 1.1;
}
.detail-drawer__definition {
  font-family: var(--font-display);
  font-weight: 300;
  font-size: 17px;
  line-height: 1.5;
  color: var(--ink-1);
  margin: 0;
}
.detail-drawer__field {
  display: grid; gap: 8px;
  padding: 16px;
  border-radius: var(--pas-radius-sm);
  background: rgba(255,255,255,0.03);
  border: 1px solid var(--pas-card-line);
}
.detail-drawer__field h4 {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--pas-accent, var(--ink-3));
  margin: 0;
}
.detail-drawer__field p,
.detail-drawer__field ul {
  font-size: 14px;
  color: var(--ink-1);
  line-height: 1.55;
  margin: 0;
}
.detail-drawer__field ul {
  padding-left: 18px;
  display: grid; gap: 4px;
}
.detail-drawer__field--bottleneck { border-color: rgba(255, 118, 118, 0.4); }
.detail-drawer__field--bottleneck h4 { color: #ff9090; }

/* ============================================================
   Layer nav (prev / next) at bottom of detail pages
   ============================================================ */
.layer-nav {
  display: grid; gap: 14px;
  grid-template-columns: 1fr;
  margin-top: clamp(48px, 7vw, 80px);
}
@media (min-width: 720px) {
  .layer-nav { grid-template-columns: 1fr 1fr 1fr; }
}
.layer-nav__cell {
  display: grid; gap: 6px;
  padding: 22px 24px;
  border-radius: var(--pas-radius);
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    linear-gradient(var(--pas-card-line-2), var(--pas-card-line-2)) border-box;
  border: 1.5px solid transparent;
  text-decoration: none;
  color: inherit;
  transition: background var(--t-fast) var(--ease), transform var(--t-fast) var(--ease), box-shadow var(--t-fast) var(--ease);
}
.layer-nav__cell:hover {
  background:
    linear-gradient(180deg, var(--pas-card-bg), var(--pas-card-bg-2)) padding-box,
    var(--rai-grad) border-box;
  transform: translateY(-2px);
  box-shadow: var(--glow-sibling);
}
.layer-nav__cell--center { text-align: center; }
.layer-nav__cell--next { text-align: right; }
.layer-nav__cell--disabled { opacity: 0.5; pointer-events: none; }
.layer-nav__label {
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--ink-3);
}
.layer-nav__title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 18px;
  letter-spacing: -0.015em;
  color: var(--ink-0);
  margin: 0;
}

/* ============================================================
   Reduced motion / accessibility
   ============================================================ */
@media (prefers-reduced-motion: reduce) {
  .layer-card, .capability-card, .trend-card, .loop-diagram__step,
  .detail-drawer, .detail-drawer__backdrop {
    transition: none !important;
  }
}

/* Focus rings — visible across all interactive elements */
.layer-card:focus-visible,
.capability-card:focus-visible,
.loop-diagram__step:focus-visible,
.pipeline__step:focus-visible,
.body-callouts button:focus-visible,
.infra-strip__items button:focus-visible {
  box-shadow: 0 0 0 2px var(--pas-accent), 0 0 0 4px rgba(0,0,0,0.4);
}