/* NestPulse design system: a hardware diagnostic bench.
   The canvas is powder coated charcoal, hairlines are machined edges, and numerals are
   silkscreened readouts. Status colors appear only as semantic LEDs: mint for healthy,
   amber for attention, coral for fault. Bone is the single neutral instrument accent. */

:root {
  --bg: #141613;
  --slab: #1a1d18;
  --inset: #0e100d;
  --line: rgba(228, 225, 211, 0.13);
  --line-strong: rgba(228, 225, 211, 0.30);
  --ink: #e8e5db;
  --muted: #a6a396;
  --faint: #8a877b;
  --accent: #f1eee3;
  --ok: #5fd3a5;
  --ok-soft: rgba(95, 211, 165, 0.12);
  --warn: #e3b264;
  --warn-soft: rgba(227, 178, 100, 0.12);
  --fault: #ef8974;
  --fault-soft: rgba(239, 137, 116, 0.13);
  --radius: 6px;
  --radius-small: 4px;
  --sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", "Cascadia Code", Menlo, Consolas, "Liberation Mono", monospace;
  --dur: 0.18s;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 4.5rem;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16.5px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

/* The bench frame: two fixed vertical hairlines that bracket the whole page on
   wide screens, like the rails of a service enclosure. */
body::before {
  content: "";
  position: fixed;
  z-index: 0;
  inset: 0;
  margin-inline: auto;
  max-width: 76rem;
  border-inline: 1px solid var(--line);
  pointer-events: none;
}

section, header, footer, main {
  position: relative;
  z-index: 1;
}

::selection {
  background: rgba(241, 238, 227, 0.22);
  color: var(--ink);
}

.wrap {
  max-width: 72rem;
  margin-inline: auto;
  padding-inline: 1.4rem;
}

.mono {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip {
  position: absolute;
  left: 1rem;
  top: -3.5rem;
  z-index: 50;
  padding: 0.6rem 1rem;
  background: var(--accent);
  color: #141613;
  border-radius: var(--radius-small);
  font-weight: 650;
  text-decoration: none;
  transition: top 0.2s ease;
}

.skip:focus-visible {
  top: 0.75rem;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 3px;
}

/* ---------------------------------- LEDs ---------------------------------- */

.led {
  display: inline-block;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  flex: none;
  background: transparent;
  box-shadow: inset 0 0 0 1.5px var(--line-strong);
}

.led-ok {
  background: var(--ok);
  box-shadow: 0 0 6px rgba(95, 211, 165, 0.45);
}

.led-warn {
  background: var(--warn);
  box-shadow: 0 0 6px rgba(227, 178, 100, 0.45);
}

.led-fault {
  background: var(--fault);
  box-shadow: 0 0 6px rgba(239, 137, 116, 0.5);
}

.led-off {
  box-shadow: inset 0 0 0 1.5px var(--line);
}

.led-dim {
  background: transparent;
  box-shadow: inset 0 0 0 1.5px var(--line-strong);
}

.led-breathe {
  animation: led-breathe 2.8s ease-in-out infinite;
}

@keyframes led-breathe {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.4; }
}

/* --------------------------------- Header --------------------------------- */

.rail {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(20, 22, 19, 0.86);
  backdrop-filter: blur(9px);
  border-bottom: 1px solid var(--line);
}

.rail-row {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  min-height: 3.5rem;
  flex-wrap: wrap;
  padding-block: 0.5rem;
}

.nameplate {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-weight: 720;
  font-size: 1.12rem;
  letter-spacing: -0.015em;
  color: var(--ink);
  text-decoration: none;
}

.nameplate .led {
  width: 9px;
  height: 9px;
}

.rail-nav {
  display: flex;
  gap: 0.2rem;
  flex-wrap: wrap;
}

.rail-nav a {
  color: var(--muted);
  text-decoration: none;
  font-family: var(--mono);
  font-size: 0.84rem;
  letter-spacing: 0.03em;
  padding: 0.4rem 0.7rem;
  border-radius: var(--radius-small);
  border: 1px solid transparent;
  transition: color var(--dur) ease, background var(--dur) ease, border-color var(--dur) ease;
}

.rail-nav a:hover {
  color: var(--ink);
  background: rgba(228, 225, 211, 0.06);
  border-color: var(--line);
}

.rail-note {
  margin: 0 0 0 auto;
  color: var(--faint);
  font-size: 0.8rem;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  letter-spacing: 0.05em;
}

/* ---------------------------------- Hero ---------------------------------- */

.hero {
  padding-block: 4.4rem 3.2rem;
}

.hero-grid {
  display: grid;
  grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
  gap: 3rem;
  align-items: start;
}

.plate-tag {
  margin: 0 0 1rem;
  color: var(--faint);
  font-size: 0.8rem;
  letter-spacing: 0.14em;
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.plate-tag::before {
  content: "";
  width: 22px;
  height: 1px;
  background: var(--line-strong);
}

.hero h1 {
  margin: 0 0 1.1rem;
  font-size: clamp(2.2rem, 5.2vw, 3.5rem);
  line-height: 1.06;
  letter-spacing: -0.03em;
  font-weight: 760;
  max-width: 20ch;
}

.hero h1 em {
  font-style: normal;
  color: var(--accent);
}

.hero-lede {
  margin: 0 0 1.8rem;
  max-width: 56ch;
  color: var(--muted);
  font-size: 1.05rem;
}

.module-index {
  list-style: none;
  margin: 0 0 1.6rem;
  padding: 0;
  border-bottom: 1px solid var(--line);
}

.module-index a {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1.2rem;
  padding: 0.72rem 0.15rem;
  border-top: 1px solid var(--line);
  text-decoration: none;
  transition: background var(--dur) ease;
}

.module-index a:hover {
  background: rgba(228, 225, 211, 0.04);
}

.module-name {
  color: var(--ink);
  font-weight: 640;
  font-size: 1rem;
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
}

.module-name::before {
  content: "";
  width: 5px;
  height: 5px;
  background: var(--line-strong);
  flex: none;
  transition: background var(--dur) ease;
}

.module-index a:hover .module-name::before,
.module-index a:focus-visible .module-name::before {
  background: var(--accent);
}

.module-desc {
  color: var(--faint);
  font-size: 0.78rem;
  text-align: right;
}

.spec-strip {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1.4rem;
  margin: 0;
  padding: 0;
  color: var(--faint);
  font-size: 0.78rem;
  letter-spacing: 0.05em;
}

.spec-strip li {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.spec-strip li::before {
  content: "";
  width: 4px;
  height: 4px;
  background: var(--line-strong);
}

/* ------------------------- The unit (hero appliance) ---------------------- */

.unit {
  position: relative;
  background: var(--slab);
  border: 1px solid var(--line-strong);
  border-radius: 10px;
  padding: 1.15rem 1.15rem 1rem;
  box-shadow: 0 30px 60px -38px rgba(0, 0, 0, 0.7), inset 0 1px 0 rgba(228, 225, 211, 0.07);
}

.screw {
  position: absolute;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--inset);
  box-shadow: inset 0 0 0 1px var(--line);
}

.screw::after {
  content: "";
  position: absolute;
  left: 1px;
  right: 1px;
  top: 50%;
  height: 1px;
  background: var(--line-strong);
  transform: rotate(45deg);
}

.screw-tl { top: 8px; left: 8px; }
.screw-tr { top: 8px; right: 8px; }
.screw-bl { bottom: 8px; left: 8px; }
.screw-br { bottom: 8px; right: 8px; }

.unit-top {
  display: flex;
  align-items: center;
  gap: 1rem;
  padding-inline: 0.25rem;
}

.unit-lamp {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--faint);
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.08em;
}

.unit-lamp .led {
  width: 6px;
  height: 6px;
}

.unit-tag {
  margin-left: auto;
  color: var(--faint);
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  border: 1px solid var(--line);
  border-radius: 3px;
  padding: 0.14rem 0.45rem;
}

.bay-wall {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 10px;
  margin-block: 0.8rem;
}

.hbay {
  background: var(--inset);
  border: 1px solid var(--line);
  border-radius: var(--radius-small);
  padding: 12px 9px 8px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.sled {
  position: relative;
  display: flex;
  align-items: flex-end;
  width: 100%;
  min-height: 96px;
  background: rgba(228, 225, 211, 0.045);
  border: 1px solid var(--line);
  border-radius: 3px;
  overflow: hidden;
}

.sled::before {
  content: "";
  position: absolute;
  top: 6px;
  left: 16%;
  right: 16%;
  height: 2px;
  border-radius: 2px;
  background: var(--line);
}

.hbay .fill {
  display: block;
  width: 100%;
  height: var(--fill, 60%);
  background: rgba(228, 225, 211, 0.24);
  border-top: 2px solid rgba(228, 225, 211, 0.5);
}

.hbay .led {
  width: 6px;
  height: 6px;
}

.unit-screen {
  background: var(--inset);
  border: 1px solid var(--line);
  border-radius: var(--radius-small);
  padding: 10px 12px 8px;
}

.trace {
  display: block;
  width: 100%;
  height: 54px;
}

.trace-base {
  fill: none;
  stroke: rgba(228, 225, 211, 0.22);
  stroke-width: 1.4;
  stroke-linejoin: round;
}

.trace-sweep {
  fill: none;
  stroke: var(--ok);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-dasharray: 42 278;
  animation: trace-march 4.6s linear infinite;
}

@keyframes trace-march {
  from { stroke-dashoffset: 320; }
  to { stroke-dashoffset: 0; }
}

.screen-readout {
  margin: 4px 0 0;
  color: var(--ok);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
}

.unit-foot {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  margin-top: 0.7rem;
  padding-inline: 0.25rem;
  color: var(--faint);
  font-size: 0.68rem;
  letter-spacing: 0.12em;
}

/* --------------------------------- Modules -------------------------------- */

.module {
  padding-block: 3rem 3.4rem;
  border-top: 1px solid var(--line);
}

.module-head {
  margin-bottom: 1.6rem;
}

.module-head h2 {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  margin: 0 0 0.55rem;
  font-size: clamp(1.6rem, 3vw, 2.05rem);
  letter-spacing: -0.02em;
  font-weight: 730;
}

.module-head h2 .led {
  width: 9px;
  height: 9px;
}

.lede {
  margin: 0;
  color: var(--muted);
  max-width: 64ch;
}

.chip-adjacent {
  display: flex;
  align-items: baseline;
  gap: 0.7rem;
  flex-wrap: wrap;
}

/* ------------------------------ Control strip ----------------------------- */

.control-strip {
  display: flex;
  flex-wrap: wrap;
  gap: 1.1rem 1.6rem;
  align-items: end;
  padding: 1.05rem 1.15rem;
  background: var(--slab);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  margin-bottom: 1.1rem;
}

.field {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
  min-width: 9rem;
}

.field-wide {
  min-width: 14rem;
  flex: 1;
}

.field label {
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.05em;
  color: var(--muted);
}

.field output {
  color: var(--accent);
  font-family: var(--mono);
  font-size: 0.82rem;
  font-variant-numeric: tabular-nums;
}

input[type="number"],
select {
  background: var(--inset);
  color: var(--ink);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-small);
  padding: 0.5rem 0.65rem;
  font: inherit;
  font-size: 0.95rem;
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
}

input[type="number"] {
  max-width: 8rem;
}

select {
  max-width: 14rem;
}

input[type="range"] {
  accent-color: var(--accent);
  width: 100%;
}

input[type="checkbox"] {
  accent-color: var(--accent);
  width: 1.05rem;
  height: 1.05rem;
}

.field-check {
  flex-direction: row;
  align-items: center;
  gap: 0.55rem;
  min-width: 0;
}

.field-check label {
  font-family: var(--sans);
  font-size: 0.9rem;
  letter-spacing: 0;
  color: var(--muted);
}

.readout-line {
  margin: 0 0 1.2rem;
  color: var(--accent);
  font-family: var(--mono);
  font-size: 0.86rem;
  border-left: 2px solid var(--line-strong);
  padding-left: 0.65rem;
}

.footnote {
  margin: 1.3rem 0 0;
  color: var(--faint);
  font-size: 0.86rem;
  max-width: 76ch;
}

.panel-error {
  margin: 1rem 0 0;
  color: var(--fault);
  font-weight: 600;
}

.noscript-note {
  margin: 1rem 1.4rem;
  padding: 1rem 1.2rem;
  border: 1px solid var(--warn);
  border-radius: var(--radius);
  color: var(--warn);
  background: var(--inset);
}

/* -------------------------------- Bay chassis ----------------------------- */

.bay-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(212px, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
}

.bay-unit {
  background: var(--bg);
  padding: 1.05rem 1.05rem 1.15rem;
  min-width: 0;
}

.bay-unit.is-fault {
  background: var(--inset);
}

.bay-unit-head {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  margin-bottom: 0.85rem;
}

.bay-unit-name {
  margin: 0;
  font-size: 1.02rem;
  font-weight: 700;
  letter-spacing: -0.01em;
}

.is-fault .bay-unit-name {
  color: var(--muted);
}

.bay-track {
  display: flex;
  gap: 3px;
  margin-bottom: 0.9rem;
}

.seg {
  flex: 1;
  min-width: 0;
  height: 13px;
  border-radius: 2px;
  background: rgba(228, 225, 211, 0.06);
  box-shadow: inset 0 0 0 1px var(--line);
}

.seg-data {
  background: rgba(228, 225, 211, 0.32);
  box-shadow: inset 0 1px 0 rgba(228, 225, 211, 0.35);
}

.seg-redundant {
  background: repeating-linear-gradient(135deg, rgba(228, 225, 211, 0.17) 0 3px, transparent 3px 7px);
  box-shadow: inset 0 0 0 1px var(--line-strong);
}

.bay-usable {
  margin: 0 0 0.5rem;
  display: flex;
  flex-direction: column;
}

.bay-usable .num {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.78rem;
  font-weight: 620;
  letter-spacing: -0.02em;
  color: var(--accent);
}

.bay-usable .sub {
  color: var(--faint);
  font-size: 0.8rem;
}

.arithmetic {
  margin: 0 0 0.9rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--muted);
  line-height: 1.55;
}

.readout {
  margin: 0 0 0.95rem;
  border-top: 1px solid var(--line);
}

.readout-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  padding: 0.32rem 0;
  border-bottom: 1px solid var(--line);
}

.readout dt {
  color: var(--faint);
  font-size: 0.82rem;
}

.readout dd {
  margin: 0;
  font-size: 0.82rem;
  color: var(--ink);
  text-align: right;
}

.bay-notes {
  margin: 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0.38rem;
}

.bay-notes li {
  position: relative;
  padding-left: 0.95rem;
  color: var(--muted);
  font-size: 0.83rem;
  line-height: 1.5;
}

.bay-notes li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 5px;
  height: 5px;
  background: var(--line-strong);
}

.bay-empty {
  margin: 0;
  font-family: var(--mono);
  font-size: 0.83rem;
  color: var(--muted);
}

/* --------------------------------- Chips ---------------------------------- */

.chip {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.16rem 0.6rem;
  border-radius: 3px;
  font-family: var(--mono);
  font-size: 0.76rem;
  font-weight: 600;
  white-space: nowrap;
  border: 1px solid var(--line);
  color: var(--muted);
}

.chip .led {
  width: 6px;
  height: 6px;
}

.chip-warn {
  background: var(--warn-soft);
  color: var(--warn);
  border-color: rgba(227, 178, 100, 0.35);
}

.chip-ok {
  background: var(--ok-soft);
  color: var(--ok);
  border-color: rgba(95, 211, 165, 0.35);
}

.chip-fault {
  background: var(--fault-soft);
  color: var(--fault);
  border-color: rgba(239, 137, 116, 0.35);
}

/* --------------------------------- Tables --------------------------------- */

.table-scroll {
  overflow-x: auto;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--slab);
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.88rem;
  min-width: 44rem;
}

.fires-table {
  min-width: 0;
}

.data-table th {
  text-align: left;
  font-family: var(--mono);
  font-weight: 500;
  color: var(--faint);
  font-size: 0.74rem;
  letter-spacing: 0.07em;
  padding: 0.72rem 0.85rem;
  border-bottom: 1px solid var(--line-strong);
  white-space: nowrap;
}

.data-table td {
  padding: 0.6rem 0.85rem;
  border-bottom: 1px solid var(--line);
  vertical-align: top;
  font-variant-numeric: tabular-nums;
}

.data-table tbody tr:not(.detail-row):hover {
  background: rgba(228, 225, 211, 0.035);
}

.data-table tbody tr:last-child td {
  border-bottom: none;
}

.fires-table th {
  letter-spacing: 0;
  font-size: 0.82rem;
}

.fires-table th[scope="row"] {
  color: var(--ink);
  font-weight: 620;
}

.model-name {
  display: block;
  font-weight: 640;
}

.model-family {
  display: block;
  color: var(--faint);
  font-family: var(--mono);
  font-size: 0.72rem;
  margin-top: 0.1rem;
}

tr.row-no-fit .model-name {
  color: var(--muted);
}

.total-cell {
  display: flex;
  flex-direction: column;
  gap: 5px;
  min-width: 7rem;
}

.util-bar {
  display: block;
  width: 100%;
  height: 4px;
  border-radius: 2px;
  background: rgba(228, 225, 211, 0.08);
  overflow: hidden;
}

.util-fill {
  display: block;
  height: 100%;
  background: rgba(228, 225, 211, 0.55);
}

.util-fill.bar-warn {
  background: var(--warn);
}

.util-fill.bar-no {
  background: var(--fault);
}

tr.detail-row > td {
  padding-top: 0;
  border-bottom: 1px solid var(--line);
}

tr.detail-row:last-child td {
  border-bottom: none;
}

/* -------------------------------- Details --------------------------------- */

details {
  border: 1px solid var(--line);
  border-radius: var(--radius-small);
  background: var(--inset);
}

.models-table details {
  border: none;
  background: transparent;
}

summary {
  cursor: pointer;
  padding: 0.5rem 0.8rem;
  color: var(--muted);
  font-family: var(--mono);
  font-weight: 600;
  font-size: 0.78rem;
  letter-spacing: 0.03em;
  list-style-position: inside;
  transition: color var(--dur) ease;
}

summary:hover {
  color: var(--ink);
}

.detail-body {
  padding: 0.25rem 0.9rem 0.9rem;
  font-size: 0.86rem;
  color: var(--muted);
}

.detail-body p {
  margin: 0.45rem 0;
}

.ladder-label {
  font-weight: 640;
  color: var(--ink);
}

.quant-ladder {
  list-style: none;
  margin: 0.4rem 0 0;
  padding: 0;
  display: grid;
  gap: 0.26rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  font-variant-numeric: tabular-nums;
}

.quant-ladder .fits {
  color: var(--ok);
}

.quant-ladder .does-not-fit {
  color: var(--faint);
}

.keep-line {
  color: var(--ok);
}

.remove-line {
  color: var(--fault);
}

/* ------------------------------- Stat strip ------------------------------- */

.stat-strip {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--slab);
  overflow: hidden;
  margin-bottom: 1.1rem;
}

.stat {
  padding: 0.9rem 1rem;
  border-left: 1px solid var(--line);
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
  min-width: 0;
}

.stat:first-child {
  border-left: none;
}

.stat .num {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: 1.4rem;
  font-weight: 620;
  letter-spacing: -0.02em;
  color: var(--accent);
}

.stat-label {
  color: var(--faint);
  font-size: 0.8rem;
}

/* --------------------------------- Ledger --------------------------------- */

.ledger {
  border-top: 1px solid var(--line);
}

.ledger-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 0.3rem 1.4rem;
  padding: 1rem 0 0.95rem;
  border-bottom: 1px solid var(--line);
}

.ledger-head {
  grid-column: 1;
  grid-row: 1;
  display: flex;
  align-items: center;
  gap: 0.55rem;
  flex-wrap: wrap;
  margin: 0;
}

.ledger-class {
  font-weight: 660;
  font-size: 0.95rem;
}

.ledger-conf {
  color: var(--faint);
  font-size: 0.76rem;
}

.ledger-bytes {
  grid-column: 2;
  grid-row: 1;
  justify-self: end;
  align-self: start;
  margin: 0;
  color: var(--accent);
  font-weight: 640;
  font-size: 0.95rem;
}

.ledger-reason {
  grid-column: 1;
  grid-row: 2;
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
  max-width: 68ch;
}

.ledger-row details {
  grid-column: 1 / -1;
  grid-row: 3;
  margin-top: 0.45rem;
}

/* ------------------------------ Rules module ------------------------------ */

.rules-layout {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 6fr);
  gap: 2rem;
  align-items: start;
}

.rules-layout h3 {
  margin: 0 0 0.8rem;
  font-size: 1.1rem;
  font-weight: 720;
  letter-spacing: -0.01em;
}

.results-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.8rem;
}

.results-head h3 {
  margin: 0;
}

.sub-head {
  margin: 1.6rem 0 0.7rem;
  font-size: 1rem;
  font-weight: 700;
}

.registry {
  border-top: 1px solid var(--line);
}

.registry-row {
  display: grid;
  gap: 0.5rem;
  padding: 0.9rem 0;
  border-bottom: 1px solid var(--line);
}

.registry-name {
  margin: 0;
  font-size: 0.95rem;
  font-weight: 660;
}

.term-row {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  margin: 0;
  padding: 0;
}

.term {
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
  font-family: var(--mono);
  font-size: 0.73rem;
  color: var(--muted);
  border: 1px solid var(--line);
  border-radius: 3px;
  padding: 0.16rem 0.5rem;
}

.term .led {
  width: 6px;
  height: 6px;
}

.term-act {
  color: var(--ink);
  border-color: var(--line-strong);
}

.validation-list {
  display: grid;
  gap: 0.45rem;
}

.validation-note {
  display: flex;
  align-items: baseline;
  gap: 0.55rem;
  margin: 0;
  color: var(--muted);
  font-size: 0.88rem;
}

.validation-note .led {
  position: relative;
  top: 1px;
}

.validation-empty,
.fault-empty {
  margin: 0;
  font-family: var(--mono);
  font-size: 0.82rem;
  color: var(--muted);
}

/* ------------------------------ Fault readout ----------------------------- */

.fault-panel {
  position: relative;
  margin-top: 1.4rem;
  background: var(--inset);
  border: 1px solid var(--line-strong);
  border-radius: var(--radius);
  padding: 1rem 1.15rem 0.6rem;
  box-shadow: inset 0 1px 0 rgba(228, 225, 211, 0.05);
}

.fault-panel-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  border-bottom: 1px solid var(--line);
  padding-bottom: 0.6rem;
}

.fault-panel-head h4 {
  margin: 0;
  font-size: 1rem;
  font-weight: 700;
}

.fault-list {
  display: grid;
}

.fault-row {
  display: grid;
  grid-template-columns: minmax(6.8rem, auto) minmax(0, 1fr);
  gap: 0.3rem 1.1rem;
  padding: 0.8rem 0;
  border-bottom: 1px solid var(--line);
}

.fault-row:last-child {
  border-bottom: none;
}

.fault-code {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0;
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.08em;
  color: var(--faint);
  white-space: nowrap;
}

.fault-kind {
  margin: 0 0 0.2rem;
  font-family: var(--mono);
  font-size: 0.74rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--muted);
}

.kind-contradiction .fault-kind {
  color: var(--fault);
}

.kind-shadowed .fault-kind {
  color: var(--warn);
}

.fault-msg {
  margin: 0;
  color: var(--ink);
  font-size: 0.9rem;
  line-height: 1.55;
}

.fault-observed {
  margin: 0.4rem 0 0;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--muted);
}

/* --------------------------------- Button --------------------------------- */

button {
  font-family: var(--mono);
  font-weight: 640;
  font-size: 0.82rem;
  color: #141613;
  background: var(--accent);
  border: 1px solid transparent;
  border-radius: var(--radius-small);
  padding: 0.5rem 1rem;
  cursor: pointer;
  transition: background var(--dur) ease, transform var(--dur) ease;
}

button:hover {
  background: #fdfbf2;
}

button:active {
  transform: translateY(1px);
}

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

.site-footer {
  border-top: 1px solid var(--line);
  margin-top: 1rem;
  padding-block: 2.3rem 2.8rem;
  color: var(--muted);
  font-size: 0.88rem;
}

.footer-mark {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin: 0 0 0.7rem;
  color: var(--accent);
  font-weight: 640;
  letter-spacing: 0.02em;
}

.site-footer p {
  margin: 0 0 0.5rem;
  max-width: 76ch;
}

.footer-fine {
  color: var(--faint);
  font-size: 0.8rem;
}

/* --------------------------------- Reveal --------------------------------- */

/* Reveal on scroll. Scoped behind html.js so the section headings, ledes and
   footnotes stay visible when JavaScript is off; app.js adds the class first. */
html.js .reveal {
  opacity: 0;
  translate: 0 14px;
  transition: opacity 0.5s ease, translate 0.5s ease;
}

html.js .reveal.in {
  opacity: 1;
  translate: 0 0;
}

/* ------------------------------- Reduced motion --------------------------- */

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  html.js .reveal {
    opacity: 1;
    translate: none;
    transition: none;
  }
  .trace-sweep {
    animation: none;
    stroke-dasharray: none;
  }
  .led-breathe {
    animation: none;
  }
  .skip,
  .rail-nav a,
  .module-index a,
  .module-name::before,
  summary,
  button,
  .util-fill {
    transition: none;
  }
}

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

@media (max-width: 1020px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 2.4rem;
  }
  .unit {
    max-width: 26rem;
  }
  .rules-layout {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 640px) {
  body {
    font-size: 15.5px;
  }
  body::before {
    display: none;
  }
  .hero {
    padding-block: 3rem 2.4rem;
  }
  .rail-note {
    display: none;
  }
  .control-strip {
    align-items: stretch;
  }
  .field,
  .field-wide {
    min-width: 100%;
  }
  .module-desc {
    display: none;
  }
  .ledger-row {
    grid-template-columns: 1fr;
  }
  .ledger-bytes {
    grid-column: 1;
    grid-row: 2;
    justify-self: start;
  }
  .ledger-reason {
    grid-row: 3;
  }
  .ledger-row details {
    grid-row: 4;
  }
  .fault-row {
    grid-template-columns: 1fr;
    gap: 0.35rem;
  }
  .stat {
    border-left: none;
    border-top: 1px solid var(--line);
  }
  .stat:first-child {
    border-top: none;
  }
  .stat-strip {
    grid-template-columns: 1fr 1fr;
  }
  .bay-wall {
    gap: 7px;
  }
  .sled {
    min-height: 76px;
  }
}