/* FREQUENCY HOUSE main stylesheet. The page is a mastering console:
   sections are channel strips, heads are scribble-strip tape, dividers are
   waveform hairlines, the booking form is a patch bay. Tokens in tokens.css. */

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--font-body);
  font-size: var(--t-body);
  line-height: var(--lh-body);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

h1, h2, h3, h4, p, ul, ol, figure, dl, dd { margin: 0; }
ul[class], ol[class] { padding: 0; list-style: none; }
img, svg, video, canvas { display: block; max-width: 100%; }
button { font: inherit; color: inherit; background: none; border: 0; padding: 0; cursor: pointer; }
a { color: inherit; }

::selection { background: var(--vu-bright); color: var(--desk); }
[data-theme="plate"] ::selection { background: var(--desk); color: var(--plate); }

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

.skip-link {
  position: fixed;
  top: var(--s-3);
  left: var(--s-3);
  z-index: var(--z-skip);
  padding: var(--s-3) var(--s-5);
  background: var(--vu-bright);
  color: var(--desk);
  border-radius: var(--r-1);
  font-family: var(--font-mono);
  font-size: var(--t-mono);
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
  text-decoration: none;
  transform: translateY(calc(-100% - 1.5rem));
}
.skip-link:focus-visible { transform: none; outline-color: var(--plate); }

/* ---------- text roles ---------- */
.display, .h1, .h2, .h3 {
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.01em;
  line-height: var(--lh-heading);
  text-wrap: balance;
  font-family: var(--font-mono);
}
.display { font-size: var(--t-display); line-height: var(--lh-tight); }
.h1 { font-size: var(--t-h1); line-height: 1; }
.h2 { font-size: var(--t-h2); }
.h3 { font-size: var(--t-h3); }

.lead {
  font-size: var(--t-lead);
  line-height: 1.45;
  max-width: var(--measure);
  text-wrap: pretty;
}
.copy { max-width: var(--measure); color: var(--muted); text-wrap: pretty; }
.copy strong { color: var(--fg); font-weight: 600; }

.mono {
  font-family: var(--font-mono);
  font-size: var(--t-mono);
  font-weight: 500;
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
}
.mono--muted { color: var(--muted); }
.mono--accent { color: var(--accent); }
.amber { color: var(--accent); }
.dim { color: var(--muted); }

/* ---------- layout primitives ---------- */
.wrap {
  width: min(100% - 2 * var(--edge), var(--max-w));
  margin-inline: auto;
}

/* ---------- channel strips (the sections) ---------- */
.strip {
  position: relative;
  padding-block: var(--strip-pad);
  background: var(--bg);
  color: var(--fg);
}
.strip--flush { padding-block: 0; }

/* strip body: fader rail column + channel content */
.strip-frame {
  display: grid;
  grid-template-columns: var(--rail-w) minmax(0, 1fr);
  gap: var(--gutter);
  align-items: stretch;
}

/* the fader: a vertical rail whose cap marks scroll position within the strip.
   Purely indicative; decorative to AT; rests at unity (30% travel) without JS
   or under reduced motion. JS drives --fader-pos between 0 and 1. */
.fader {
  --fader-pos: 0.3; /* unity gain rest state */
  position: relative;
  height: 100%;
  min-height: 9rem;
}
.fader::before { /* rail slot */
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: 3px;
  transform: translateX(-50%);
  background: var(--bg-3);
  border-radius: 2px;
}
[data-theme="plate"] .fader::before { background: rgba(32, 32, 36, 0.28); }
.fader::after { /* dB ticks */
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: calc(50% + 6px);
  width: 8px;
  background: repeating-linear-gradient(
    to bottom,
    var(--line) 0,
    var(--line) 1px,
    transparent 1px,
    transparent 12.5%
  );
}
.fader-cap {
  position: absolute;
  left: 50%;
  top: calc(var(--fader-pos) * (100% - 2.2rem));
  width: clamp(1.15rem, 1.8vw, 1.6rem);
  height: 2.2rem;
  transform: translateX(-50%);
  background: linear-gradient(to bottom, var(--bg-3) 0 44%, var(--accent) 44% 56%, var(--bg-3) 56% 100%);
  border: 1px solid var(--line-strong);
  border-radius: var(--r-cap);
  box-shadow: var(--shadow-cap);
  transition: top 80ms linear;
}
[data-theme="plate"] .fader-cap {
  background: linear-gradient(to bottom, var(--desk-3) 0 44%, var(--vu-bright) 44% 56%, var(--desk-3) 56% 100%);
}

/* scribble-strip tape: the section head kicker */
.scribble {
  display: inline-block;
  background: var(--tape);
  color: var(--tape-ink);
  font-family: var(--font-mono);
  font-size: var(--t-mono);
  font-weight: 700;
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
  padding: 0.5em 1em;
  transform: rotate(-0.7deg);
  clip-path: polygon(0.4% 8%, 99.4% 0%, 100% 92%, 0.8% 100%);
}

.strip-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--s-4);
  margin-bottom: clamp(2.2rem, 5vh, 4rem);
}
.strip-head .h2 { width: 100%; margin-top: var(--s-4); }

/* waveform hairline divider between strips */
.waveline {
  display: block;
  width: 100%;
  height: 34px;
  color: var(--line-strong);
}
.waveline svg { width: 100%; height: 100%; }

/* ---------- transport bar (header) ---------- */
/* The bar is a faceplate: solid milled silver, one VU hairline along its bottom
   edge. It carries data-theme="plate", so every control inside reads the
   faceplate semantics (ink-strength amber accent) with nothing restyled by hand. */
.transport {
  position: fixed;
  inset-inline: 0;
  top: 0;
  z-index: var(--z-transport);
  background: var(--bg);
  border-bottom: 1px solid var(--accent-fill);
  color: var(--fg);
}
.transport .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--s-4);
  padding-block: var(--s-3);
}
.bus-brand {
  display: inline-flex;
  align-items: center;
  gap: var(--s-3);
  text-decoration: none;
  font-family: var(--font-mono);
  font-weight: 800;
  letter-spacing: 0.06em;
  font-size: 0.95rem;
  text-transform: uppercase;
  white-space: nowrap;
}
.bus-brand svg { width: 20px; height: 20px; color: var(--accent); }

.bus-nav { display: flex; gap: var(--s-5); }
.bus-nav a {
  font-family: var(--font-mono);
  font-size: var(--t-mono);
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
  text-decoration: none;
  opacity: 0.75;
  transition: opacity var(--dur-1) ease;
}
.bus-nav a:hover, .bus-nav a[aria-current="true"] { opacity: 1; }
.bus-nav a[aria-current="true"] { color: var(--accent); }

.bus-readout { min-width: 11ch; text-align: right; }

.patch-cta {
  font-family: var(--font-mono);
  font-size: var(--t-mono);
  font-weight: 700;
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
  text-decoration: none;
  padding: var(--s-2) var(--s-4);
  border: 1px solid var(--accent);
  color: var(--accent);
  border-radius: var(--r-1);
  transition: background-color var(--dur-1) ease, color var(--dur-1) ease;
  white-space: nowrap;
}
.patch-cta:hover { background: var(--accent); color: var(--bg); }
.bus-right { display: flex; align-items: center; gap: var(--s-4); }

.patch-menu-btn {
  display: none;
  font-family: var(--font-mono);
  font-size: var(--t-mono);
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
  padding: var(--s-2) var(--s-4);
  border: 1px solid currentColor;
  border-radius: var(--r-1);
}

/* menu overlay: the patch overlay */
.patch-overlay {
  position: fixed;
  inset: 0;
  z-index: var(--z-patch-overlay);
  background: var(--desk);
  color: var(--plate);
  display: none;
  flex-direction: column;
  justify-content: space-between;
  padding: var(--s-8) var(--edge) var(--s-6);
}
.patch-overlay.is-open { display: flex; overflow-y: auto; overscroll-behavior: contain; }
.patch-overlay nav { display: flex; flex-direction: column; gap: var(--s-3); }
.patch-overlay nav a {
  font-family: var(--font-mono);
  font-size: clamp(1.6rem, 7vw, 3.2rem);
  font-weight: 800;
  text-transform: uppercase;
  text-decoration: none;
  line-height: 1.15;
  display: flex;
  align-items: baseline;
  gap: var(--s-4);
}
.patch-overlay nav a .mono { color: var(--muted); }
.patch-overlay-foot { display: grid; gap: var(--s-4); justify-items: start; }
.patch-close {
  position: absolute;
  top: var(--s-5);
  right: var(--edge);
  font-family: var(--font-mono);
  font-size: var(--t-mono);
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
  padding: var(--s-2) var(--s-4);
  border: 1px solid var(--line-strong);
  border-radius: var(--r-1);
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.7em;
  padding: 0.95em 1.7em;
  border-radius: var(--r-1);
  background: var(--accent);
  color: var(--bg);
  font-family: var(--font-mono);
  font-size: var(--t-mono);
  font-weight: 700;
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
  text-decoration: none;
  transition: background-color var(--dur-1) ease, color var(--dur-1) ease;
}
.btn:hover { background: var(--bright); }
[data-theme="plate"] .btn { background: var(--desk); color: var(--plate); }
[data-theme="plate"] .btn:hover { background: var(--bright); }
.btn--jack {
  background: transparent;
  color: var(--fg);
  box-shadow: inset 0 0 0 1px var(--line-strong);
}
.btn--jack:hover { background: transparent; color: var(--accent); box-shadow: inset 0 0 0 1px var(--accent); }
[data-theme="plate"] .btn--jack { background: transparent; color: var(--fg); }
[data-theme="plate"] .btn--jack:hover { color: var(--bright); box-shadow: inset 0 0 0 1px var(--bright); }
.btn .btn-jackpin { transition: transform var(--dur-2) var(--ease-out); }
.btn:hover .btn-jackpin { transform: translateX(4px); }

/* ---------- master bus (hero) ---------- */
.master {
  min-height: 92svh;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  padding-top: calc(var(--strip-pad) + var(--s-8));
  padding-bottom: var(--s-7);
  overflow: clip;
}
.master-tapes {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s-3) var(--s-4);
  margin-bottom: var(--s-6);
}
.master-wordmark { width: 100%; height: auto; user-select: none; }
.master-base {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  flex-wrap: wrap;
  gap: var(--s-6);
  margin-top: var(--s-6);
  padding-top: var(--s-5);
  border-top: 1px solid var(--line);
}
.master-base .lead { max-width: 33rem; }
.master-ctas { display: flex; gap: var(--s-3); flex-wrap: wrap; }

/* static VU dial in the hero: inline SVG, decorative */
.master-vu { color: var(--muted); }
.master-vu .vu-needle { stroke: var(--vu-bright); }
.master-vu .vu-face { stroke: var(--line-strong); }

/* ---------- signal chain (services) ---------- */
.chain { border-top: 1px solid var(--line); }
.chain-row {
  display: grid;
  grid-template-columns: 6ch minmax(0, 1fr) minmax(0, 2fr) auto;
  gap: var(--gutter);
  align-items: baseline;
  padding-block: clamp(1.3rem, 2.8vh, 2rem);
  border-bottom: 1px solid var(--line);
  transition: background-color var(--dur-2) ease;
}
.chain-row:hover { background: var(--bg-2); }
.chain-row h3 { font-size: var(--t-h3); font-family: var(--font-mono); text-transform: uppercase; }
.chain-num { color: var(--accent); }
.chain-desc { color: var(--muted); max-width: 46ch; }
.chain-io { display: flex; flex-direction: column; gap: var(--s-1); text-align: right; }

/* ---------- the room (monitoring) ---------- */
.room-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.15fr) minmax(0, 1fr);
  gap: clamp(2rem, 5vw, 5rem);
  align-items: start;
}
.rackmount { border: 1px solid var(--line-strong); border-radius: var(--r-2); overflow: hidden; }
.rack-unit {
  display: grid;
  grid-template-columns: minmax(7ch, auto) 1fr;
  gap: var(--gutter);
  align-items: baseline;
  padding: var(--s-4) var(--s-5);
  border-bottom: 1px solid var(--line);
  background: var(--bg-2);
}
.rack-unit:last-child { border-bottom: 0; }
.rack-unit .mono:first-child { color: var(--accent); }
.rack-unit p { font-size: var(--t-small); color: var(--fg); }
.room-copy { display: grid; gap: var(--s-4); }

/* ---------- session pass (process) ---------- */
.pass-track {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: var(--gutter);
}
.pass-step {
  position: relative;
  padding-top: var(--s-5);
  border-top: 1px solid var(--line);
}
.pass-step::before {
  content: "";
  position: absolute;
  top: -1px;
  left: 0;
  width: 0;
  height: 3px;
  background: var(--accent);
  transition: width var(--dur-3) var(--ease-out);
}
.pass-step.is-inview::before { width: 3.2rem; }
.pass-step .mono { display: block; margin-bottom: var(--s-3); }
.pass-step h3 { font-size: var(--t-h3); font-family: var(--font-mono); text-transform: uppercase; margin-bottom: var(--s-3); }
.pass-step p { color: var(--muted); font-size: var(--t-small); }
.pass-step .pass-give { margin-top: var(--s-3); color: var(--fg); }

/* ---------- meter band (facts about the desk itself) ---------- */
.meters {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  border-block: 1px solid var(--line);
}
.meter-cell { padding: var(--s-6) var(--s-5); border-inline-start: 1px solid var(--line); }
.meter-cell:first-child { border-inline-start: 0; }
.meter-value {
  font-family: var(--font-mono);
  font-size: clamp(2.2rem, 4.6vw, 3.8rem);
  font-weight: 800;
  line-height: 1;
}
.meter-cell .mono { display: block; margin-top: var(--s-3); }
.meter-note { display: block; margin-top: var(--s-2); font-size: var(--t-small); color: var(--fg); max-width: 26ch; }

/* ---------- rate strip (faceplate teaser) + rate card page ---------- */
.rate-lines { border-top: 1px solid var(--line); }
.rate-line {
  display: grid;
  grid-template-columns: minmax(0, 2fr) minmax(0, 3fr) auto;
  gap: var(--gutter);
  align-items: baseline;
  padding-block: clamp(1.1rem, 2.4vh, 1.7rem);
  border-bottom: 1px solid var(--line);
}
.rate-line h3 { font-size: var(--t-h3); font-family: var(--font-mono); text-transform: uppercase; }
.rate-line p { color: var(--muted); font-size: var(--t-small); max-width: 44ch; }
.rate-price { font-family: var(--font-mono); font-weight: 700; font-size: var(--t-body); white-space: nowrap; }
.rate-fine { margin-top: var(--s-5); font-size: var(--t-small); color: var(--muted); max-width: var(--measure); }

/* sample chip: honesty marker on demo content */
.sample-chip {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 0.62rem;
  font-weight: 700;
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
  padding: 0.3em 0.7em;
  border: 1px solid var(--line-strong);
  border-radius: var(--r-1);
  color: var(--muted);
  vertical-align: middle;
}

/* interior banner strip */
.banner { padding-top: calc(var(--strip-pad) + var(--s-7)); padding-bottom: var(--s-7); border-bottom: 1px solid var(--line); }
.banner .crumbs { display: flex; gap: var(--s-2); align-items: baseline; margin-bottom: var(--s-4); }
.banner .crumbs a { text-decoration: none; color: var(--muted); }
.banner .crumbs a:hover { color: var(--fg); }
.banner .h1 { margin-top: var(--s-3); }

/* spec table on the rate card */
.spec-sheet { display: grid; gap: 0; border: 1px solid var(--line-strong); border-radius: var(--r-2); overflow: hidden; }
.spec-row {
  display: grid;
  grid-template-columns: minmax(10ch, 16rem) 1fr;
  gap: var(--gutter);
  padding: var(--s-4) var(--s-5);
  border-bottom: 1px solid var(--line);
  background: var(--bg-2);
}
.spec-row:last-child { border-bottom: 0; }
.spec-row dt { font-family: var(--font-mono); font-size: var(--t-mono); letter-spacing: var(--track-mono); text-transform: uppercase; color: var(--muted); }
.spec-row dd { font-size: var(--t-small); }

/* ---------- talkback (FAQ accordion) ---------- */
.talk-list { border-top: 1px solid var(--line); }
.talk-item { border-bottom: 1px solid var(--line); }
.talk-trigger {
  width: 100%;
  display: grid;
  grid-template-columns: 6ch 1fr auto;
  gap: var(--gutter);
  align-items: baseline;
  padding-block: clamp(1.2rem, 2.4vh, 1.8rem);
  text-align: left;
}
.talk-trigger:hover .talk-q { color: var(--accent); }
.talk-q {
  font-family: var(--font-mono);
  font-size: clamp(1.15rem, 2.4vw, 1.8rem);
  font-weight: 700;
  text-transform: uppercase;
  transition: color var(--dur-1) ease;
}
.talk-led {
  align-self: center;
  width: 0.65rem;
  height: 0.65rem;
  border-radius: 50%;
  border: 1px solid var(--line-strong);
  background: transparent;
  transition: background-color var(--dur-1) ease, box-shadow var(--dur-1) ease;
}
.talk-trigger[aria-expanded="true"] .talk-led {
  background: var(--vu-bright);
  border-color: var(--vu-bright);
  box-shadow: 0 0 8px rgba(232, 176, 75, 0.7);
}
.talk-panel { overflow: hidden; }
.talk-panel[hidden] { display: none; }
.talk-panel-inner {
  padding: 0 0 var(--s-6) calc(6ch + var(--gutter));
  color: var(--muted);
  max-width: 52rem;
}

/* ---------- patch bay (booking form) ---------- */
.patchbay-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(0, 1fr);
  gap: clamp(2rem, 5vw, 5rem);
  margin-top: var(--s-7);
  align-items: start;
}
.patchbay { display: grid; gap: var(--s-5); }
.jack { display: grid; gap: var(--s-2); position: relative; }
.jack label {
  font-family: var(--font-mono);
  font-size: var(--t-mono);
  font-weight: 700;
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
}
.jack label::before { content: "\25CE\00a0\00a0"; color: var(--accent); }
.jack-hint { font-size: var(--t-small); color: var(--muted); margin: 0; }
.jack input,
.jack textarea {
  font: inherit;
  color: var(--fg);
  background: var(--bg-2);
  border: 1px solid var(--line-strong);
  border-radius: var(--r-1);
  padding: var(--s-3) var(--s-4);
  transition: border-color var(--dur-1) ease;
}
.jack input:focus-visible,
.jack textarea:focus-visible { outline: none; border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent); }
.jack textarea { resize: vertical; min-height: 7rem; }
.jack select {
  font: inherit;
  color: var(--fg);
  background-color: var(--bg-2);
  border: 1px solid var(--line-strong);
  border-radius: var(--r-1);
  padding: var(--s-3) 2.2rem var(--s-3) var(--s-4);
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='8'%3E%3Cpath d='M1 1l5 5 5-5' fill='none' stroke='%239A9BA3' stroke-width='2'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right var(--s-4) center;
  transition: border-color var(--dur-1) ease;
}
.jack select:focus-visible { outline: none; border-color: var(--accent); box-shadow: 0 0 0 1px var(--accent); }
.jack select option { color: var(--desk); background: var(--plate); }
.jack.is-cold input,
.jack.is-cold textarea { border-color: var(--accent); }
.jack-error {
  font-family: var(--font-mono);
  font-size: var(--t-mono);
  letter-spacing: var(--track-mono);
  text-transform: uppercase;
  color: var(--accent);
  margin: 0;
}
.patch-errors {
  border: 1px solid var(--accent);
  border-radius: var(--r-2);
  padding: var(--s-4) var(--s-5);
}
.patch-errors p { margin: 0 0 var(--s-2); }
.patch-errors ul { margin: 0; padding-left: 1.2em; display: grid; gap: var(--s-1); }
.patch-errors a { color: var(--accent); }
.patch-status { color: var(--fg); max-width: var(--measure); }
.patch-status:empty { display: none; }
.patchbay[aria-busy="true"] .btn { opacity: 0.6; pointer-events: none; }
.patch-fallback {
  border: 1px solid var(--line-strong);
  border-radius: var(--r-2);
  padding: var(--s-5);
  display: grid;
  gap: var(--s-4);
}
/* the display above outranks the UA [hidden] rule: put the panel back in its
   case until a send actually fails */
.patch-fallback[hidden] { display: none; }
.patch-fallback textarea {
  font-family: var(--font-mono);
  font-size: var(--t-small);
  color: var(--fg);
  background: var(--bg-2);
  border: 1px solid var(--line);
  border-radius: var(--r-1);
  padding: var(--s-3);
  width: 100%;
  resize: vertical;
}
.patch-fallback-actions { display: flex; gap: var(--s-3); flex-wrap: wrap; }
/* hard-wired bypass notice: shown whenever main.js is off or failed to load */
.patch-noscript {
  border-left: 2px solid var(--accent);
  padding-left: var(--s-4);
  font-size: var(--t-small);
  color: var(--fg);
  max-width: var(--measure);
  margin: 0;
}
.js .patch-noscript { display: none; }
.patch-noscript a { color: var(--accent); }
/* what the browser keeps while the sheet is being typed */
.patch-keep { max-width: var(--measure); margin: 0; font-size: var(--t-small); color: var(--muted); }
/* honeypot: visually gone, skipped by keyboard and assistive tech */
.tb-field {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}
.patch-aside { display: grid; gap: var(--s-5); justify-items: start; }
.patch-steps { display: grid; gap: var(--s-3); }
.patch-steps li { display: flex; gap: var(--s-3); align-items: baseline; }
.patch-steps .mono { color: var(--accent); }

.patch-cta-line { font-family: var(--font-mono); font-size: var(--t-h2); font-weight: 800; text-transform: uppercase; line-height: 1.1; }
.patch-cta-line a { text-decoration: none; color: var(--accent); }
.patch-cta-line a:hover, .patch-cta-line a:focus-visible { text-decoration: underline; text-decoration-thickness: 3px; text-underline-offset: 6px; }

/* ---------- back panel (footer) ---------- */
.backpanel { border-top: 1px solid var(--line-strong); background: var(--bg); padding-top: var(--s-8); }
.backpanel-grid {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: var(--gutter);
  padding-bottom: var(--s-7);
}
.backpanel-grid h3 { margin-bottom: var(--s-4); }
.backpanel-grid ul { display: grid; gap: var(--s-2); }
.backpanel-grid a { text-decoration: none; color: var(--muted); transition: color var(--dur-1) ease; }
.backpanel-grid a:hover { color: var(--fg); }
.backpanel-serial {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: var(--s-3);
  padding-block: var(--s-5);
  border-top: 1px solid var(--line);
}

/* ---------- reveal motion ---------- */
.reveal { opacity: 1; transform: none; }
.js .reveal {
  opacity: 0;
  transform: translateY(1.4rem);
  transition: opacity var(--dur-3) ease, transform var(--dur-3) var(--ease-out);
}
.js .reveal.is-inview { opacity: 1; transform: none; }
.js .reveal[data-delay="1"] { transition-delay: 90ms; }
.js .reveal[data-delay="2"] { transition-delay: 180ms; }
.js .reveal[data-delay="3"] { transition-delay: 270ms; }

/* ---------- styleguide page ---------- */
.sg-swatches { display: grid; grid-template-columns: repeat(auto-fit, minmax(11rem, 1fr)); gap: var(--gutter); }
.sg-swatch { border: 1px solid var(--line); border-radius: var(--r-2); overflow: hidden; }
.sg-swatch-color { height: 6rem; }
.sg-swatch dl { padding: var(--s-4); display: grid; gap: var(--s-1); }
.sg-swatch dt { font-family: var(--font-mono); font-size: var(--t-mono); letter-spacing: var(--track-mono); text-transform: uppercase; color: var(--muted); }
.sg-swatch dd { font-family: var(--font-mono); font-size: var(--t-small); }
.sg-block { padding-block: var(--s-7); border-top: 1px solid var(--line); }
.sg-row { display: grid; grid-template-columns: 14rem 1fr; gap: var(--gutter); align-items: baseline; padding-block: var(--s-4); }
.sg-note { color: var(--muted); max-width: var(--measure); margin-top: var(--s-3); }
.sg-demo { display: flex; flex-wrap: wrap; gap: var(--s-4); align-items: center; }

/* ---------- error page (dead channel) ---------- */
.dead-channel {
  min-height: 100svh;
  display: grid;
  place-content: center;
  justify-items: center;
  text-align: center;
  gap: var(--s-5);
  padding-block: var(--s-8);
}
.dead-channel .display { font-size: clamp(5rem, 24vw, 16rem); }
.dead-channel .fader { min-height: 12rem; width: var(--rail-w); }
.dead-routes { display: flex; gap: var(--s-3); flex-wrap: wrap; justify-content: center; }

/* ---------- responsive ---------- */
@media (max-width: 63.9rem) {
  .bus-nav, .bus-readout { display: none; }
  .patch-menu-btn { display: inline-flex; }
  /* no-JS (or failed-JS) fallback: static nav returns, dead menu button goes */
  html:not(.js) .bus-nav { display: flex; flex-wrap: wrap; gap: var(--s-2) var(--s-4); justify-content: flex-end; }
  html:not(.js) .patch-menu-btn { display: none; }
  .patch-cta { display: none; }
  .strip-frame { grid-template-columns: 1fr; }
  .fader { display: none; }
  .chain-row { grid-template-columns: 5ch 1fr; }
  .chain-desc { grid-column: 2; }
  .chain-io { grid-column: 2; flex-direction: row; flex-wrap: wrap; gap: var(--s-1) var(--s-3); text-align: left; }
  .room-grid { grid-template-columns: 1fr; }
  .pass-track { grid-template-columns: repeat(2, 1fr); row-gap: var(--s-7); }
  .meters { grid-template-columns: repeat(2, 1fr); }
  .meter-cell:nth-child(odd) { border-inline-start: 0; }
  .meter-cell:nth-child(n + 3) { border-top: 1px solid var(--line); }
  .rate-line { grid-template-columns: 1fr auto; }
  .rate-line p { grid-column: 1 / -1; }
  .patchbay-grid { grid-template-columns: 1fr; }
  .backpanel-grid { grid-template-columns: 1fr 1fr; row-gap: var(--s-6); }
  .sg-row { grid-template-columns: 1fr; }
  .spec-row { grid-template-columns: 1fr; gap: var(--s-1); }
}

@media (max-width: 40rem) {
  .pass-track { grid-template-columns: 1fr; }
  .meters { grid-template-columns: 1fr; }
  .meter-cell { border-inline-start: 0; }
  .meter-cell:nth-child(n + 2) { border-top: 1px solid var(--line); }
  .talk-trigger { grid-template-columns: 4ch 1fr auto; }
  .talk-panel-inner { padding-left: 0; }
  .master-base { flex-direction: column; align-items: flex-start; }
}

/* ---------- cross-page transitions (progressive enhancement) ---------- */
@media (prefers-reduced-motion: no-preference) {
  @view-transition { navigation: auto; }
}

/* ---------- preferences ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .js .reveal { opacity: 1; transform: none; transition: none; }
  .fader-cap { transition: none; top: calc(0.3 * (100% - 2.2rem)); } /* rests at unity */
  .btn, .btn .btn-jackpin, .talk-led, .pass-step::before, .transport { transition: none; }
  .pass-step.is-inview::before { width: 3.2rem; }
}

@media (forced-colors: active) {
  .btn, .patch-cta { border: 1px solid ButtonText; }
  .scribble { border: 1px solid CanvasText; }
  .fader-cap { border: 1px solid CanvasText; }
}