/* ScopeLab — the page is a bench instrument: enamel panel, engraved grooves,
   inset screens. Colour is data, never decoration. */

:root {
  --panel:      #ccd1ca;
  --panel-hi:   #e4e8e1;
  --panel-lo:   #aeb5ac;
  --groove:     #9aa39c;
  --ink:        #161b18;
  --ink-2:      #495049;
  --ink-3:      #6f7873;

  --screen:     #070d0d;
  --grat:       #16302c;
  --grat-axis:  #2a4b45;
  --screen-ink: #7fa39c;

  --ch-a:       #f0b429;   /* signal as generated    */
  --ch-b:       #2ed3c6;   /* anything digital       */
  --ch-c:       #9b8cf5;   /* after the analog path  */
  --ghost:      #5d6b6a;   /* what arrived from up-chain */
  --fold:       #c05c9c;   /* folded copies          */
  --nyq:        #e2574a;   /* Nyquist boundary       */

  --ok:         #2c7a55;
  --warn:       #9a6b0d;
  --bad:        #b23a2c;

  --sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", "Cascadia Mono", Menlo, Consolas, monospace;

  --gap: 22px;
  --edge: 1px solid var(--groove);
}

[data-theme="night"] {
  --ghost:      #6c7b79;
  --panel:      #23282a;
  --panel-hi:   #2f3538;
  --panel-lo:   #191d1f;
  --groove:     #101415;
  --ink:        #e6ebe8;
  --ink-2:      #a6b0ac;
  --ink-3:      #7e8884;
  --ok:         #57c48c;
  --warn:       #d9a63c;
  --bad:        #e0705e;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } * { transition: none !important; } }

body {
  margin: 0;
  background: var(--panel);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 15px;
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 { font-weight: 620; letter-spacing: -0.014em; margin: 0; }
p { margin: 0; }
code, kbd { font-family: var(--mono); font-size: 0.92em; }

.sr-only {
  position: absolute; width: 1px; height: 1px; overflow: hidden;
  clip: rect(0 0 0 0); clip-path: inset(50%); white-space: nowrap;
}

:focus-visible {
  outline: 2px solid var(--ch-b);
  outline-offset: 2px;
}

/* ---------- top rail ---------- */

.rail {
  position: sticky; top: 0; z-index: 20;
  display: flex; align-items: center; gap: 20px;
  padding: 0 20px; height: 54px;
  background: linear-gradient(180deg, var(--panel-hi), var(--panel));
  border-bottom: var(--edge);
  box-shadow: 0 1px 0 var(--panel-hi);
}

.wordmark {
  font-size: 17px; letter-spacing: -0.03em; font-weight: 700;
}
.wordmark span { font-weight: 340; }

.views { display: flex; gap: 2px; margin-left: 6px; }
.viewtab {
  border: 0; background: none; cursor: pointer;
  font: inherit; font-size: 13.5px; color: var(--ink-2);
  padding: 6px 11px; border-radius: 2px;
}
.viewtab:hover { color: var(--ink); background: color-mix(in srgb, var(--panel-hi) 70%, transparent); }
.viewtab.is-on { color: var(--ink); box-shadow: inset 0 -2px 0 var(--ink); }

.rail-readout {
  margin-left: auto; display: flex; align-items: center; gap: 9px;
  font-family: var(--mono); font-size: 12px; color: var(--ink-2);
  font-variant-numeric: tabular-nums;
}
.lamp {
  width: 9px; height: 9px; border-radius: 50%;
  background: var(--ok);
  box-shadow: 0 0 0 1px color-mix(in srgb, var(--ink) 25%, transparent) inset;
  flex: none;
}

.chip {
  font: inherit; font-size: 12.5px; cursor: pointer;
  color: var(--ink-2); background: linear-gradient(180deg, var(--panel-hi), var(--panel));
  border: var(--edge); border-radius: 3px; padding: 5px 10px;
}
.chip:hover { color: var(--ink); border-color: var(--ink-3); }
.chip:active { background: var(--panel-lo); }
.chip.wide { width: 100%; margin-top: 14px; padding: 8px; }

/* ---------- shell ---------- */

main { max-width: 1560px; margin: 0 auto; padding: var(--gap) 20px 60px; }
.view { display: none; }
.view.is-on { display: block; }

/* ---------- the instrument ---------- */

.instrument {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 340px;
  gap: var(--gap);
  align-items: start;
}
.screen-column { min-width: 0; }

.screen {
  position: relative; margin: 0;
  background: var(--screen);
  border: 1px solid #05090a;
  border-radius: 3px;
  box-shadow:
    inset 0 0 0 1px #0e1a19,
    inset 0 2px 14px #000a,
    0 1px 0 var(--panel-hi);
  aspect-ratio: 21 / 9;
}
.screen canvas { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }
.screen-wide { aspect-ratio: 26 / 7; }
.screen-field { aspect-ratio: 16 / 9; max-height: 62vh; }

/* bezel soft keys, sitting under the screen like the real thing */
.softkeys { margin-top: 10px; }
.softkey-rail {
  display: grid; grid-template-columns: repeat(auto-fit, minmax(158px, 1fr));
  border: var(--edge); border-radius: 3px; overflow: hidden;
  background: var(--panel-lo);
  gap: 1px;
}
.softkey {
  border: 0; cursor: pointer; text-align: left;
  padding: 9px 11px 10px;
  background: linear-gradient(180deg, var(--panel-hi), var(--panel));
  font: inherit; color: var(--ink-2);
}
.softkey b { display: block; font-size: 12.5px; font-weight: 620; color: var(--ink); }
.softkey span { display: block; font-size: 11px; line-height: 1.35; margin-top: 2px; }
.softkey:hover { background: var(--panel-hi); }
.softkey.is-on { background: var(--panel-lo); box-shadow: inset 0 2px 4px #0002; }
.softkey-hint { font-size: 12px; color: var(--ink-3); margin-top: 7px; }

/* verdict — one strong sentence, no box */
.verdict { margin: 20px 0 16px; padding-left: 13px; border-left: 3px solid var(--ok); max-width: 74ch; }
.verdict[data-level="warn"] { border-left-color: var(--warn); }
.verdict[data-level="bad"]  { border-left-color: var(--bad); }
.verdict-head { font-size: 19px; font-weight: 620; letter-spacing: -0.015em; }
.verdict-body { color: var(--ink-2); margin-top: 4px; font-size: 14px; }

/* measurement strip */
.measure {
  display: flex; flex-wrap: wrap; margin: 0;
  border-top: var(--edge); border-bottom: var(--edge);
  box-shadow: 0 1px 0 var(--panel-hi), inset 0 1px 0 var(--panel-hi);
}
.measure > div { flex: 1 1 150px; padding: 11px 16px 12px; border-left: var(--edge); }
.measure > div:first-child { border-left: 0; padding-left: 0; }
.measure dt { font-size: 11.5px; color: var(--ink-3); }
.measure dd {
  margin: 3px 0 0; font-family: var(--mono); font-size: 19px;
  font-variant-numeric: tabular-nums; letter-spacing: -0.02em;
}
.measure .is-key dd { color: var(--bad); }
.measure .is-key.is-clean dd { color: var(--ink); }

/* ---------- control column ---------- */

.controls { display: block; }
.controls fieldset {
  border: 0; margin: 0 0 4px; padding: 0 0 16px;
  border-bottom: var(--edge);
  box-shadow: 0 1px 0 var(--panel-hi);
}
.controls fieldset + fieldset { padding-top: 16px; }
.controls legend {
  font-size: 12px; font-weight: 640; color: var(--ink-3);
  padding: 0; margin-bottom: 12px;
}

.knob { margin: 0 0 15px; display: grid; grid-template-columns: 1fr auto; align-items: baseline; gap: 3px 8px; }
.knob label { font-size: 13px; color: var(--ink-2); }
.knob output {
  font-family: var(--mono); font-size: 12.5px; font-variant-numeric: tabular-nums;
  color: var(--ink); text-align: right;
}
.knob input[type=range] { grid-column: 1 / -1; }
.knob.is-primary label { color: var(--ink); font-weight: 600; }
.knob.is-primary output { color: var(--ch-b); }
[data-theme="day"] .knob.is-primary output { color: #0f7a72; }

input[type=range] {
  -webkit-appearance: none; appearance: none;
  width: 100%; height: 20px; background: none; cursor: pointer; margin: 4px 0 0;
}
input[type=range]::-webkit-slider-runnable-track {
  height: 4px; border-radius: 2px;
  background: linear-gradient(180deg, var(--groove), var(--panel-lo));
  box-shadow: inset 0 1px 2px #0003;
}
input[type=range]::-moz-range-track {
  height: 4px; border-radius: 2px; background: var(--groove);
  box-shadow: inset 0 1px 2px #0003;
}
input[type=range]::-webkit-slider-thumb {
  -webkit-appearance: none; width: 13px; height: 19px; margin-top: -7px;
  border-radius: 2px; border: 1px solid var(--groove);
  background: linear-gradient(180deg, var(--panel-hi) 45%, var(--panel-lo));
  box-shadow: 0 1px 2px #0004;
}
input[type=range]::-moz-range-thumb {
  width: 13px; height: 19px; border-radius: 2px; border: 1px solid var(--groove);
  background: linear-gradient(180deg, var(--panel-hi) 45%, var(--panel-lo));
}
.is-primary input[type=range]::-webkit-slider-thumb { border-color: #0f7a72; }

.select-row { display: flex; align-items: center; justify-content: space-between; margin-bottom: 16px; }
.select-row label { font-size: 13px; color: var(--ink-2); }
select {
  font: inherit; font-size: 13px; color: var(--ink);
  background: linear-gradient(180deg, var(--panel-hi), var(--panel));
  border: var(--edge); border-radius: 3px; padding: 6px 8px; min-width: 145px;
}

.switch { display: flex; align-items: center; gap: 9px; font-size: 13px; color: var(--ink-2); margin: 9px 0; }
.switch input { accent-color: #0f7a72; width: 15px; height: 15px; }
[data-theme="night"] .switch input { accent-color: var(--ch-b); }

.segmented { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px; background: var(--groove);
  border: var(--edge); border-radius: 3px; overflow: hidden; margin-bottom: 10px; }
.segmented label { position: relative; }
.segmented input { position: absolute; opacity: 0; inset: 0; cursor: pointer; }
.segmented span {
  display: block; text-align: center; padding: 7px 4px; font-size: 12px; color: var(--ink-2);
  background: linear-gradient(180deg, var(--panel-hi), var(--panel)); cursor: pointer;
}
.segmented input:checked + span { background: var(--panel-lo); color: var(--ink); font-weight: 600; box-shadow: inset 0 2px 4px #0002; }
.segmented input:focus-visible + span { outline: 2px solid var(--ch-b); outline-offset: -2px; }

.fieldnote { font-size: 12px; color: var(--ink-3); line-height: 1.45; margin: 0 0 12px; }

/* ---------- spectrum block ---------- */

.spectrum-block { margin-top: 34px; }
.block-head { max-width: 72ch; margin-bottom: 14px; }
.block-head h2 { font-size: 20px; margin-bottom: 5px; }
.block-head p { color: var(--ink-2); font-size: 14px; }
.block-head.wide { max-width: 78ch; margin: 6px 0 18px; }

.figure-note {
  display: flex; flex-wrap: wrap; gap: 18px; align-items: center;
  margin-top: 9px; font-size: 12px; color: var(--ink-3);
}
.key { width: 13px; height: 3px; display: inline-block; margin-right: 7px; vertical-align: middle; }
.key-a { background: var(--ch-a); }
.key-b { background: var(--ch-b); }
.key-fold { background: var(--fold); }
.key-nyq { background: var(--nyq); }

/* ---------- alias field ---------- */

.field-controls {
  display: grid; grid-template-columns: 1fr 1fr 220px; gap: 26px;
  align-items: end; margin-top: 16px; padding-top: 16px; border-top: var(--edge);
  box-shadow: inset 0 1px 0 var(--panel-hi);
}
.field-result { display: grid; gap: 2px; }
.field-result span { font-size: 12px; color: var(--ink-3); }
.field-result strong {
  font-family: var(--mono); font-size: 24px; font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
}

/* ---------- notes ---------- */

.notes { margin: 0; display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 46px; }
.notes > div { padding: 16px 0; border-top: var(--edge); box-shadow: inset 0 1px 0 var(--panel-hi); }
.notes dt { font-weight: 620; font-size: 14.5px; }
.notes dd { margin: 5px 0 0; color: var(--ink-2); font-size: 14px; max-width: 60ch; }

.keys-block { margin-top: 34px; padding-top: 18px; border-top: var(--edge); }
.keys-block h3 { font-size: 15px; margin-bottom: 10px; }
.keylist { list-style: none; padding: 0; margin: 0 0 12px; display: flex; flex-wrap: wrap; gap: 8px 26px; }
.keylist li { display: flex; align-items: center; gap: 7px; font-size: 13px; color: var(--ink-2); }
kbd {
  border: var(--edge); border-bottom-width: 2px; border-radius: 3px;
  padding: 1px 6px; background: var(--panel-hi); font-size: 11.5px; color: var(--ink);
}

.colophon {
  border-top: var(--edge); box-shadow: inset 0 1px 0 var(--panel-hi);
  padding: 16px 20px 40px; color: var(--ink-3); font-size: 12.5px;
}
.colophon p { max-width: 1560px; margin: 0 auto; }

/* ---------- responsive ---------- */

@media (max-width: 1080px) {
  .instrument { grid-template-columns: 1fr; }
  .controls { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 26px; }
  .controls fieldset { padding-top: 16px; }
  .notes { grid-template-columns: 1fr; }
  .field-controls { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 720px) {
  .rail { gap: 10px; height: auto; padding: 8px 12px; flex-wrap: wrap; position: static; }
  .rail-readout { order: 4; width: 100%; margin-left: 0; }
  main { padding: 14px 12px 40px; }
  .instrument, .controls { grid-template-columns: 1fr; }
  .screen { aspect-ratio: 4 / 3; }
  .screen-wide { aspect-ratio: 4 / 3; }
  .softkey-rail { grid-template-columns: 1fr 1fr; }
  .measure > div { flex-basis: 50%; border-left: 0; padding-left: 0; }
  .field-controls { grid-template-columns: 1fr; gap: 12px; }
  #linkBtn, #themeBtn { font-size: 12px; padding: 4px 8px; }
}

/* ================================================================== *
 * Shared furniture for the added views
 * ================================================================== */

.stage-head { max-width: 78ch; margin: 4px 0 20px; }
.stage-head h2 { font-size: 22px; margin-bottom: 6px; }
.stage-head p { color: var(--ink-2); font-size: 14.5px; }

.lab-notice {
  font-size: 12.5px; color: var(--ink-2); line-height: 1.55;
  margin: 14px 0 0; padding-left: 13px; border-left: 2px solid var(--groove);
  max-width: 88ch; min-height: 1em;
}
.lab-notice:empty { display: none; }

.notes-tight { margin-top: 6px; }
.key-c { background: var(--ch-c); }
.key-ghost { background: var(--ghost); }

.controls fieldset.stage-set legend::before {
  content: ""; display: inline-block; width: 6px; height: 6px;
  border-radius: 50%; background: var(--ch-b); margin-right: 7px;
  vertical-align: 1px;
}
.controls fieldset.stage-set[data-stage="afe"] legend::before,
.controls fieldset.stage-set[data-stage="aa"]  legend::before { background: var(--ch-c); }

/* ================================================================== *
 * Signal chain
 * ================================================================== */

.chain-bar {
  display: grid; grid-template-columns: minmax(220px, 320px) auto 1fr;
  gap: 18px; align-items: end;
  padding-bottom: 16px; margin-bottom: 4px;
  border-bottom: var(--edge); box-shadow: 0 1px 0 var(--panel-hi);
}
.chain-bar .knob { margin: 0; }
.chain-flag { font-size: 12.5px; color: var(--warn); line-height: 1.5; align-self: center; }

.chain { display: grid; gap: 0; }

.stage {
  display: grid; grid-template-columns: 340px minmax(0, 1fr);
  gap: 0 26px; align-items: start;
  padding: 20px 0 20px 26px;
  position: relative;
  border-top: var(--edge); box-shadow: inset 0 1px 0 var(--panel-hi);
}
.stage:first-child { border-top: 0; box-shadow: none; }

/* the rail: a wire running down the left, with a node at each stage */
.stage::before {
  content: ""; position: absolute; left: 7px; top: 0; bottom: 0;
  width: 1px; background: var(--groove);
}
.stage:first-child::before { top: 34px; }
.stage:last-child::before  { bottom: calc(100% - 34px); }
.stage::after {
  content: ""; position: absolute; left: 3px; top: 30px;
  width: 9px; height: 9px; border-radius: 50%;
  background: var(--ch-b); box-shadow: 0 0 0 3px var(--panel);
}
.stage[data-stage="src"]::after { background: var(--ch-a); }
.stage[data-stage="afe"]::after,
.stage[data-stage="aa"]::after  { background: var(--ch-c); }
.stage.is-out::after { background: var(--panel-lo); box-shadow: 0 0 0 3px var(--panel), inset 0 0 0 1px var(--groove); }

.stage.is-out .stage-rail h3,
.stage.is-out .stage-blurb,
.stage.is-out .stage-controls { opacity: 0.42; }
.stage.is-out .stage-controls { pointer-events: none; }

.stage-rail h3 {
  font-size: 16px; display: flex; align-items: baseline; gap: 9px; margin-bottom: 6px;
}
.stage-n {
  font-family: var(--mono); font-size: 12px; color: var(--ink-3);
  font-weight: 400; font-variant-numeric: tabular-nums;
}
.stage-fixed, .stage-blurb { font-size: 12.5px; color: var(--ink-3); line-height: 1.5; }
.stage-blurb { margin: 6px 0 14px; max-width: 46ch; }
.stage-switch { margin: 2px 0 0; }
.stage-controls .knob { margin-bottom: 13px; }
.stage-controls .select-row { margin-bottom: 13px; }
.stage-metric {
  font-family: var(--mono); font-size: 11.5px; color: var(--ink-2);
  line-height: 1.65; margin-top: 12px; max-width: 52ch;
  font-variant-numeric: tabular-nums;
}

.stage-screen {
  margin: 0; position: relative;
  background: var(--screen); border: 1px solid #05090a; border-radius: 3px;
  box-shadow: inset 0 0 0 1px #0e1a19, inset 0 2px 12px #000a;
  aspect-ratio: 24 / 5; min-height: 132px;
}
.stage-screen canvas { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }

/* ================================================================== *
 * Front end
 * ================================================================== */

.front {
  display: grid; grid-template-columns: minmax(0, 1fr) 340px;
  gap: var(--gap); align-items: start;
}
.front-main { min-width: 0; }
.screen-front { aspect-ratio: 22 / 8; }
.front-pair { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; margin-top: 12px; }
.screen-edge { aspect-ratio: 16 / 9; }
.front-controls fieldset:last-child { border-bottom: 0; box-shadow: none; }

.ratio-rail { display: flex; flex-wrap: wrap; gap: 6px; margin-bottom: 10px; }
.chip.ratio { padding: 5px 11px; font-variant-numeric: tabular-nums; }
.chip.ratio.is-on {
  background: var(--panel-lo); color: var(--ink);
  border-color: var(--ink-3); box-shadow: inset 0 2px 4px #0002;
}

#feMeasure { margin-top: 16px; }

/* ================================================================== *
 * Instruments
 * ================================================================== */

.inst-source {
  display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)) auto;
  gap: 14px 26px; align-items: end;
  padding: 16px 0 18px; margin-bottom: 4px;
  border-top: var(--edge); border-bottom: var(--edge);
  box-shadow: inset 0 1px 0 var(--panel-hi), 0 1px 0 var(--panel-hi);
}
.inst-source .knob, .inst-source .select-row { margin: 0; }
.inst-jump { display: flex; flex-wrap: wrap; gap: 6px; }

.lanes { display: grid; }

.lane {
  display: grid;
  grid-template-columns: 250px minmax(0, 1fr);
  grid-template-areas: "id screen" "id verdict";
  gap: 0 24px;
  padding: 18px 0;
  border-top: var(--edge); box-shadow: inset 0 1px 0 var(--panel-hi);
}
.lane:first-child { border-top: 0; box-shadow: none; }
.lane-id { grid-area: id; }
.lane-screen { grid-area: screen; }
.lane-verdict { grid-area: verdict; }

.lane-tier {
  font-family: var(--mono); font-size: 12px; color: var(--ink-3);
  letter-spacing: 0.02em;
}
.lane-id h3 { font-size: 16.5px; margin: 3px 0 4px; }
.lane-class { font-size: 12.5px; color: var(--ink-3); }
.lane-spec {
  display: flex; flex-wrap: wrap; gap: 4px 6px; margin: 10px 0 10px;
}
.lane-spec span {
  font-family: var(--mono); font-size: 11px; color: var(--ink-2);
  border: var(--edge); border-radius: 2px; padding: 2px 6px;
  background: var(--panel-hi); font-variant-numeric: tabular-nums;
}
.lane-note { font-size: 12.5px; color: var(--ink-3); line-height: 1.5; max-width: 40ch; }

.lane-screen {
  margin: 0; position: relative;
  background: var(--screen); border: 1px solid #05090a; border-radius: 3px;
  box-shadow: inset 0 0 0 1px #0e1a19, inset 0 2px 12px #000a;
  aspect-ratio: 22 / 5; min-height: 128px;
}
.lane-screen canvas { position: absolute; inset: 0; width: 100%; height: 100%; display: block; }

.lane-verdict {
  font-size: 13px; color: var(--ink-2); line-height: 1.55;
  margin-top: 10px; padding-left: 11px; border-left: 2px solid var(--ok);
  max-width: 92ch;
}
.lane-verdict[data-level="warn"] { border-left-color: var(--warn); }
.lane-verdict[data-level="bad"]  { border-left-color: var(--bad); }

.band-block { margin-top: 38px; }
.band-block .block-head { margin-top: 26px; }
.band-block .block-head:first-child { margin-top: 0; }
.screen-band { aspect-ratio: 20 / 7; min-height: 260px; }

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

@media (max-width: 1180px) {
  .stage { grid-template-columns: 300px minmax(0, 1fr); }
  .lane { grid-template-columns: 210px minmax(0, 1fr); }
  .inst-source { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .inst-jump { grid-column: 1 / -1; }
}

@media (max-width: 1080px) {
  .front { grid-template-columns: 1fr; }
  .front-controls { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 26px; }
  .chain-bar { grid-template-columns: 1fr; align-items: start; }
}

@media (max-width: 820px) {
  .stage {
    grid-template-columns: 1fr; gap: 14px; padding-left: 22px;
  }
  .stage-screen { aspect-ratio: 16 / 6; min-height: 120px; }
  .lane { grid-template-columns: 1fr; grid-template-areas: "id" "screen" "verdict"; gap: 12px; }
  .lane-screen { aspect-ratio: 16 / 6; }
  .lane-note { max-width: none; }
  .front-pair { grid-template-columns: 1fr; }
  .front-controls { grid-template-columns: 1fr; }
  .screen-front { aspect-ratio: 4 / 3; }
  .screen-band { aspect-ratio: 3 / 4; }
  .inst-source { grid-template-columns: 1fr; }
}