/* Internet Noises: editorial dark theme.
   Chart colours follow the dataviz reference palette (dark steps); see js/viz/theme.js. */

:root {
  color-scheme: dark;
  --page: #0d0d0d;
  --surface: #1a1a19;
  --surface-2: #222220;
  --surface-3: #2a2a27;
  --grid: #2c2c2a;
  --axis: #383835;
  --line: rgba(255, 255, 255, 0.1);
  --ink: #ffffff;
  --ink-2: #c3c2b7;
  --ink-3: #898781;
  --text: #ece9e1;
  --s1: #3987e5;
  --s2: #d95926;
  --s3: #199e70;
  --s4: #c98500;
  --s5: #d55181;
  --s6: #008300;
  --s7: #9085e9;
  --good: #0ca30c;
  --warning: #fab219;
  --critical: #d03b3b;
  --accent: #e8b04a;
  --link: #9cc3f5;
  --focus: #ffd479;
  --serif: 'Iowan Old Style', 'Palatino Linotype', Palatino, 'Book Antiqua', Georgia, serif;
  --sans: system-ui, -apple-system, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  --mono: ui-monospace, 'SF Mono', Menlo, Consolas, 'Liberation Mono', monospace;
  --col: 44rem;
  --wide: 75rem;
  --bar-h: 3.25rem;
}

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

[hidden] {
  display: none !important;
}

html {
  scroll-padding-top: calc(var(--bar-h) + 1rem);
  scroll-padding-bottom: 1rem;
  -webkit-text-size-adjust: 100%;
}

@media (prefers-reduced-motion: no-preference) {
  html {
    scroll-behavior: smooth;
  }
}

body {
  margin: 0;
  background: var(--page);
  color: var(--text);
  font-family: var(--serif);
  font-size: 1.1875rem;
  line-height: 1.62;
  overflow-x: clip;
}

a {
  color: var(--link);
  text-underline-offset: 0.18em;
}
a:hover {
  color: #c6dcfa;
}

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

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

.skip {
  position: absolute;
  left: 1rem;
  top: -4rem;
  background: var(--focus);
  color: #000;
  padding: 0.5rem 1rem;
  z-index: 100;
  font-family: var(--sans);
}
.skip:focus {
  top: 0.5rem;
}
.noscript {
  margin: 0;
  padding: 0.75rem 1rem;
  background: var(--surface-2);
  font-family: var(--sans);
  font-size: 0.9rem;
  text-align: center;
}

code,
kbd {
  font-family: var(--mono);
  font-size: 0.86em;
  background: var(--surface-2);
  padding: 0.05em 0.35em;
  border-radius: 4px;
}

/* ---------- masthead and audio bar ---------- */
.masthead {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(13, 13, 13, 0.94);
  border-bottom: 1px solid var(--line);
  font-family: var(--sans);
  font-size: 0.875rem;
}
@supports (backdrop-filter: blur(8px)) {
  .masthead {
    background: rgba(13, 13, 13, 0.82);
    backdrop-filter: blur(8px);
  }
}
.masthead-inner {
  max-width: var(--wide);
  margin: 0 auto;
  min-height: var(--bar-h);
  display: flex;
  align-items: center;
  gap: 1rem;
  padding: 0.35rem 1rem;
}
.brand {
  color: var(--ink);
  text-decoration: none;
  font-weight: 600;
  letter-spacing: 0.01em;
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  white-space: nowrap;
}
.brand-wave {
  width: 1.6rem;
  height: 0.9rem;
  background: linear-gradient(var(--s3), var(--s3)) center/100% 2px no-repeat;
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 32 18'%3E%3Cpath d='M1 9 Q4 1 7 9 T13 9 T19 9 T25 9 T31 9' stroke='black' stroke-width='2.4' fill='none'/%3E%3C/svg%3E") center/contain no-repeat;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 32 18'%3E%3Cpath d='M1 9 Q4 1 7 9 T13 9 T19 9 T25 9 T31 9' stroke='black' stroke-width='2.4' fill='none'/%3E%3C/svg%3E") center/contain no-repeat;
  background: var(--s3);
}
.chapters {
  margin-right: auto;
}
.chapters-menu {
  position: relative;
}
.chapters-menu summary {
  list-style: none;
  cursor: pointer;
  color: var(--ink-2);
  padding: 0.45rem 0.7rem;
  border: 1px solid var(--line);
  border-radius: 6px;
  min-height: 2.25rem;
  display: inline-flex;
  align-items: center;
}
.chapters-menu summary::-webkit-details-marker {
  display: none;
}
.chapters-menu summary::after {
  content: '▾';
  margin-left: 0.4rem;
  font-size: 0.75em;
}
.chapters-menu ol {
  position: absolute;
  top: calc(100% + 0.4rem);
  left: 0;
  margin: 0;
  padding: 0.5rem;
  list-style: none;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  min-width: 15rem;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}
.chapters-menu a {
  display: block;
  padding: 0.45rem 0.6rem;
  border-radius: 4px;
  color: var(--ink-2);
  text-decoration: none;
}
.chapters-menu a:hover,
.chapters-menu a:focus-visible {
  background: var(--surface-2);
  color: var(--ink);
}
.audiobar {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}
.now-playing {
  color: var(--ink-3);
  font-size: 0.8rem;
  max-width: 14rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.vol input {
  width: 6.5rem;
  vertical-align: middle;
}

/* ---------- article layout ---------- */
main {
  padding: 0 1.25rem 4rem;
}
article > section {
  max-width: var(--col);
  margin: 0 auto;
}
.hero {
  padding: clamp(3rem, 9vw, 6.5rem) 0 2.5rem;
}
.kicker,
.chapter-no {
  font-family: var(--sans);
  font-size: 0.78rem;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--accent);
  margin: 0 0 0.6rem;
}
/* Chapters open with a small framed tag, like a channel label on an instrument, not a rule. */
.chapter-no {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  width: fit-content;
  padding: 0.3rem 0.75rem 0.3rem 0.6rem;
  border: 1px solid rgba(232, 176, 74, 0.5);
  border-radius: 4px;
  background: rgba(232, 176, 74, 0.06);
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.16em;
  margin-bottom: 1rem;
}
.chapter-no::before {
  content: '';
  flex: 0 0 auto;
  width: 1.3rem;
  height: 0.75rem;
  background: currentColor;
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 32 18'%3E%3Cpath d='M1 9 Q4 1 7 9 T13 9 T19 9 T25 9 T31 9' stroke='black' stroke-width='2.4' fill='none'/%3E%3C/svg%3E") center/contain no-repeat;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 32 18'%3E%3Cpath d='M1 9 Q4 1 7 9 T13 9 T19 9 T25 9 T31 9' stroke='black' stroke-width='2.4' fill='none'/%3E%3C/svg%3E") center/contain no-repeat;
}
h1,
h2,
h3 {
  font-family: var(--sans);
  color: var(--ink);
  line-height: 1.18;
  font-weight: 650;
  letter-spacing: -0.01em;
}
h1 {
  font-size: clamp(2.3rem, 6.2vw, 4rem);
  margin: 0 0 1.2rem;
  max-width: 15ch;
}
h2 {
  font-size: clamp(1.7rem, 3.6vw, 2.3rem);
  margin: 0 0 1rem;
}
h3 {
  font-size: 1.22rem;
  margin: 2.2rem 0 0.6rem;
}
.dek {
  font-size: clamp(1.2rem, 2.2vw, 1.42rem);
  line-height: 1.5;
  color: var(--ink-2);
  margin: 0 0 2rem;
}
.hero-cta {
  margin: 0 0 0.9rem;
}
.hero-note {
  font-family: var(--sans);
  font-size: 0.86rem;
  color: var(--ink-3);
  max-width: 38rem;
}
.legend-kinds {
  margin: 2rem 0 0;
  display: grid;
  gap: 0.5rem;
  font-family: var(--sans);
  font-size: 0.86rem;
  color: var(--ink-2);
}
.legend-kinds div {
  display: flex;
  gap: 0.75rem;
  align-items: baseline;
}
.legend-kinds dt {
  flex: 0 0 9.5rem;
}
.legend-kinds dd {
  margin: 0;
}

.chapter {
  padding: 4.5rem 0 1rem;
  margin-top: 2.5rem !important;
}
.chapter p,
.chapter li {
  max-width: var(--col);
}
.acts,
.three {
  padding-left: 1.3rem;
}
.acts li,
.three li {
  margin-bottom: 0.7rem;
}
.small {
  font-size: 0.92rem;
  color: var(--ink-2);
}

.cite {
  font-family: var(--sans);
  font-size: 0.68em;
  vertical-align: super;
  line-height: 0;
  text-decoration: none;
  padding: 0 0.08em;
  color: var(--link);
}
.term {
  color: inherit;
  text-decoration: underline dotted var(--ink-3);
  text-underline-offset: 0.2em;
  text-decoration-thickness: 1.5px;
}
.term:hover,
.term:focus-visible {
  text-decoration-color: var(--link);
}
.term-card {
  position: absolute;
  z-index: 60;
  max-width: 22rem;
  background: var(--surface-2);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.7rem 0.85rem;
  font-family: var(--sans);
  font-size: 0.86rem;
  line-height: 1.45;
  color: var(--ink-2);
  box-shadow: 0 12px 30px rgba(0, 0, 0, 0.55);
}
.term-card strong {
  color: var(--ink);
  display: block;
  margin-bottom: 0.2rem;
}
.term-card a {
  display: inline-block;
  margin-top: 0.35rem;
}

.note {
  background: var(--surface);
  border-left: 3px solid var(--accent);
  border-radius: 0 8px 8px 0;
  padding: 0.4rem 1.25rem 0.8rem;
  margin: 2rem 0;
}
.note h3 {
  margin-top: 0.8rem;
}
.deeper {
  margin: 1.5rem 0;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.2rem 1.1rem;
}
.deeper > summary {
  cursor: pointer;
  font-family: var(--sans);
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--ink);
  padding: 0.75rem 0;
  min-height: 2.75rem;
}
.deeper[open] > summary {
  border-bottom: 1px solid var(--line);
  margin-bottom: 0.6rem;
}
.deeper p,
.deeper li {
  font-size: 1rem;
}
.simplifications > summary::before {
  content: '◇ ';
  color: var(--s3);
}

.badge {
  display: inline-block;
  font-family: var(--sans);
  font-size: 0.68rem;
  font-weight: 650;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: 0.18rem 0.5rem;
  border-radius: 99px;
  border: 1px solid;
  color: var(--ink);
  white-space: nowrap;
  vertical-align: middle;
}
.badge-historical {
  border-color: var(--s4);
  background: rgba(201, 133, 0, 0.16);
}
.badge-recreation {
  border-color: var(--s5);
  background: rgba(213, 81, 129, 0.16);
}
.badge-model {
  border-color: var(--s3);
  background: rgba(25, 158, 112, 0.16);
}

/* ---------- figures (instrument panels) ---------- */
.fig {
  margin: 2.2rem 0;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 10px;
  font-family: var(--sans);
  font-size: 0.92rem;
  line-height: 1.45;
}
.fig-wide {
  margin-left: calc(50% - min(var(--wide) / 2, 50vw - 1rem));
  margin-right: calc(50% - min(var(--wide) / 2, 50vw - 1rem));
}
.fig-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.5rem 0.75rem;
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--line);
}
.fig-label {
  font-family: var(--mono);
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--ink-3);
}
.fig-title {
  color: var(--ink);
  font-weight: 600;
}
.fig-body {
  padding: 1rem;
}
.fig-loading {
  color: var(--ink-3);
  margin: 0;
}
.fig figcaption {
  padding: 0.75rem 1rem 1rem;
  border-top: 1px solid var(--line);
  color: var(--ink-2);
  font-size: 0.86rem;
}
.fig .cite {
  font-size: 0.75em;
}

.panel-row {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  gap: 0.6rem 1rem;
  margin: 0 0 0.8rem;
}
.panel-row.tight {
  gap: 0.4rem 0.6rem;
}
.panel-row .spacer {
  flex: 1;
}
.subhead {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--ink-3);
  margin: 1.1rem 0 0.4rem;
  font-weight: 600;
}
.view-label {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  font-size: 0.78rem;
  color: var(--ink-2);
  margin: 0.6rem 0 0.25rem;
}
.view-label strong {
  color: var(--ink);
  font-weight: 600;
}
.readout {
  font-family: var(--mono);
  font-size: 0.8rem;
  color: var(--ink-2);
  min-height: 1.3em;
  margin: 0.35rem 0 0;
  font-variant-numeric: tabular-nums;
}
.hint {
  font-size: 0.8rem;
  color: var(--ink-3);
}
.warn-list {
  margin: 0.4rem 0;
  padding: 0;
  list-style: none;
  font-size: 0.85rem;
}
.warn-list li {
  padding: 0.35rem 0.6rem;
  border-radius: 6px;
  margin: 0.25rem 0;
  background: rgba(250, 178, 25, 0.1);
  border-left: 3px solid var(--warning);
  color: var(--ink-2);
}
.warn-list li.is-error {
  background: rgba(208, 59, 59, 0.12);
  border-left-color: var(--critical);
}
.warn-list li::before {
  content: '⚠ ';
  color: var(--warning);
}
.warn-list li.is-error::before {
  content: '✕ ';
  color: var(--critical);
}

/* canvases */
.cv {
  position: relative;
  width: 100%;
  background: var(--surface);
  border-radius: 6px;
  user-select: none;
  -webkit-user-select: none;
}
.cv-layer {
  position: absolute;
  inset: 0;
  display: block;
}
.cv.is-interactive {
  cursor: crosshair;
  touch-action: pan-y;
}
.wave.is-interactive {
  cursor: pointer;
}
.cv:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 2px;
}

/* ---------- controls ---------- */
.btn {
  font-family: var(--sans);
  font-size: 0.88rem;
  color: var(--ink);
  background: var(--surface-2);
  border: 1px solid #3c3c38;
  border-radius: 7px;
  min-height: 2.5rem;
  padding: 0.4rem 0.85rem;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  line-height: 1.1;
}
.btn:hover {
  background: var(--surface-3);
  border-color: #55554f;
}
.btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}
.btn[aria-pressed='true'] {
  background: #3a3a35;
  border-color: var(--ink-3);
}
.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #161208;
  font-weight: 650;
}
.btn-primary:hover {
  background: #f2c160;
  border-color: #f2c160;
}
.btn-large {
  font-size: 1.05rem;
  min-height: 3.1rem;
  padding: 0.6rem 1.35rem;
  border-radius: 99px;
}
.btn-icon {
  min-width: 2.5rem;
  justify-content: center;
  padding: 0.3rem 0.55rem;
}
.icon {
  display: block;
  flex: 0 0 auto;
  width: 1.15rem;
  height: 1.15rem;
}
#mute .icon-muted,
#mute[aria-pressed='true'] .icon-sound {
  display: none;
}
#mute[aria-pressed='true'] .icon-muted {
  display: block;
}
.btn-small {
  min-height: 2rem;
  font-size: 0.8rem;
  padding: 0.25rem 0.6rem;
}

.ctl {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
  min-width: 9rem;
  font-family: var(--sans);
}
.panel-row {
  font-family: var(--sans);
}
.ctl label,
.ctl legend {
  font-size: 0.76rem;
  color: var(--ink-2);
}
.ctl-range {
  min-width: 12rem;
  flex: 1 1 12rem;
  max-width: 22rem;
  display: grid;
  grid-template-columns: 1fr auto;
  grid-template-areas: 'label value' 'input input';
  column-gap: 0.6rem;
}
.ctl-range label {
  grid-area: label;
}
.ctl-range output {
  grid-area: value;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
}
.ctl-range input {
  grid-area: input;
  width: 100%;
}
input[type='range'] {
  accent-color: var(--accent);
  height: 1.75rem;
  margin: 0;
}
select,
input[type='text'],
input[type='number'],
textarea {
  font-family: var(--sans);
  font-size: 0.95rem;
  color: var(--ink);
  background: #121211;
  border: 1px solid #3c3c38;
  border-radius: 6px;
  padding: 0.45rem 0.6rem;
  min-height: 2.5rem;
}
input[type='text'].big {
  font-size: 1.05rem;
  width: 100%;
}
.ctl-toggle {
  flex-direction: row;
  align-items: center;
  gap: 0.5rem;
  min-width: 0;
}
.ctl-toggle input {
  width: 1.15rem;
  height: 1.15rem;
  accent-color: var(--accent);
}
.ctl-toggle label {
  font-size: 0.85rem;
  color: var(--ink);
}
.ctl-hint {
  display: block;
  color: var(--ink-3);
  font-size: 0.75rem;
}
.ctl-seg {
  border: 0;
  padding: 0;
  margin: 0;
  min-width: 0;
}
.seg-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  border: 1px solid #3c3c38;
  border-radius: 7px;
  overflow: hidden;
  width: fit-content;
}
.seg-item input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}
.seg-item label {
  display: inline-flex;
  align-items: center;
  min-height: 2.4rem;
  padding: 0.3rem 0.75rem;
  font-size: 0.84rem;
  color: var(--ink-2);
  background: #151514;
  cursor: pointer;
  border-right: 1px solid #3c3c38;
}
.seg-item:last-child label {
  border-right: 0;
}
.seg-item input:checked + label {
  background: #3a3a35;
  color: var(--ink);
}
.seg-item input:focus-visible + label {
  outline: 2px solid var(--focus);
  outline-offset: -2px;
}

.advanced {
  margin-top: 0.8rem;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0 0.85rem;
  background: #161615;
}
.advanced > summary {
  cursor: pointer;
  padding: 0.6rem 0;
  font-size: 0.84rem;
  color: var(--ink-2);
  min-height: 2.5rem;
}
.advanced[open] > summary {
  border-bottom: 1px solid var(--line);
  margin-bottom: 0.6rem;
}
.advanced .panel-row {
  margin-bottom: 0.6rem;
}

/* ---------- Figure 1: player ---------- */
.player-top {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  align-items: center;
  margin-bottom: 0.75rem;
}
.time {
  font-family: var(--mono);
  font-size: 0.9rem;
  color: var(--ink);
  font-variant-numeric: tabular-nums;
  min-width: 8.5rem;
}
.modem-face {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin: 0.2rem 0 0.8rem;
  padding: 0.5rem 0.75rem;
  background: #121211;
  border: 1px solid var(--line);
  border-radius: 8px;
}
.leds {
  display: flex;
  gap: 0.7rem;
  align-items: center;
}
.led {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  gap: 0.15rem;
  font-family: var(--mono);
  font-size: 0.66rem;
  color: var(--ink-3);
}
.led i {
  width: 0.62rem;
  height: 0.62rem;
  border-radius: 50%;
  background: #3b1515;
  border: 1px solid #5a2a2a;
}
.led.on i {
  background: #ff5a4a;
  border-color: #ff8a7a;
  box-shadow: 0 0 6px rgba(255, 90, 74, 0.7);
}
.led.on {
  color: var(--ink);
}
.terminal {
  flex: 1;
  min-width: 14rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: #b9d7b9;
  line-height: 1.35;
  min-height: 2.7em;
  white-space: pre-wrap;
}
.terminal .dim {
  color: var(--ink-3);
}
.speaker-state {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  font-size: 0.8rem;
  color: var(--ink-2);
}
.speaker-state .icon,
.tl-spk .icon {
  width: 1rem;
  height: 1rem;
}
.tl-spk-label {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
}
.muted-banner {
  font-size: 0.8rem;
  color: var(--ink);
  background: rgba(255, 255, 255, 0.06);
  border-radius: 6px;
  padding: 0.25rem 0.6rem;
}

.timeline {
  position: relative;
  --label-w: 8.2rem;
  margin: 0.9rem 0 0.4rem;
}
.tl-row {
  display: grid;
  grid-template-columns: var(--label-w) 1fr;
  align-items: center;
  margin-bottom: 4px;
}
.tl-label {
  font-size: 0.76rem;
  color: var(--ink-2);
  padding-right: 0.5rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.tl-track {
  position: relative;
  height: 28px;
  background: #121211;
  border-radius: 4px;
}
.tl-phases .tl-track {
  height: 24px;
  background: transparent;
}
.tl-phase {
  position: absolute;
  top: 2px;
  bottom: 2px;
  background: rgba(255, 255, 255, 0.06) padding-box;
  background: color-mix(in srgb, var(--c) 20%, transparent) padding-box;
  border-right: 2px solid transparent; /* gap between neighbouring phases */
  border-radius: 4px;
  font-size: 0.7rem;
  color: var(--ink-2);
  overflow: hidden;
  white-space: nowrap;
  padding: 0 4px;
  display: flex;
  gap: 0.3rem;
  align-items: center;
}
.tl-swatch {
  width: 0.5rem;
  height: 0.5rem;
  border-radius: 2px;
  flex: 0 0 auto;
}
.tl-stage {
  position: absolute;
  top: 3px;
  bottom: 3px;
  border: 0;
  border-radius: 3px;
  padding: 0 4px;
  font-family: var(--sans);
  font-size: 0.68rem;
  font-weight: 600;
  text-align: left;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
  cursor: pointer;
  box-shadow: 0 0 0 1px var(--surface);
  min-height: 0;
}
.tl-stage-label {
  pointer-events: none;
}
.tl-stage.is-active {
  box-shadow: 0 0 0 2px var(--ink);
  z-index: 2;
}
.tl-stage.is-selected {
  outline: 2px solid var(--focus);
  outline-offset: 1px;
  z-index: 3;
}
.tl-speaker .tl-track {
  height: 20px;
}
.tl-spk {
  position: absolute;
  top: 3px;
  bottom: 3px;
  font-size: 0.68rem;
  color: var(--ink-2);
  padding: 0 0.4rem;
  display: flex;
  align-items: center;
  white-space: nowrap;
  overflow: hidden;
  border-radius: 3px;
}
.tl-spk.on {
  background: rgba(255, 255, 255, 0.07);
}
.tl-spk.off {
  background: repeating-linear-gradient(135deg, transparent 0 6px, rgba(255, 255, 255, 0.05) 6px 8px);
}
.tl-cursor {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 2px;
  margin-left: -1px;
  background: var(--ink);
  left: calc(var(--label-w) + (100% - var(--label-w)) * var(--x, 0));
  pointer-events: none;
  display: none;
  z-index: 4;
}

.stage-panels {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
  gap: 0.8rem;
  margin-top: 0.9rem;
}
.stage-card {
  background: #151514;
  background: color-mix(in srgb, var(--c, #55554f) 7%, #151514);
  border: 1px solid var(--line);
  border-color: color-mix(in srgb, var(--c, #55554f) 60%, transparent);
  border-radius: 8px;
  padding: 0.7rem 0.85rem;
}
.stage-card h4 {
  margin: 0 0 0.25rem;
  font-size: 0.95rem;
  color: var(--ink);
}
.stage-card .who {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--ink-3);
}
.stage-card .who::before {
  content: '';
  flex: 0 0 auto;
  width: 0.6rem;
  height: 0.6rem;
  border-radius: 2px;
  background: var(--c, var(--ink-3));
}
.stage-card p {
  margin: 0.3rem 0;
  color: var(--ink-2);
}
.stage-card details {
  margin-top: 0.4rem;
}
.stage-card details summary {
  cursor: pointer;
  font-size: 0.8rem;
  color: var(--ink);
  min-height: 1.8rem;
}
.stage-card details p {
  font-size: 0.84rem;
}
.fidelity {
  font-size: 0.72rem;
  color: var(--ink-2);
  border: 1px solid var(--line);
  border-radius: 99px;
  padding: 0.05rem 0.5rem;
  display: inline-block;
  margin-top: 0.35rem;
}
.stage-actions {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
  margin-top: 0.5rem;
}
.decode-out {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--ink-2);
  background: #101010;
  border-radius: 6px;
  padding: 0.5rem 0.6rem;
  margin-top: 0.5rem;
  white-space: pre-wrap;
  word-break: break-word;
}
.stage-list {
  font-size: 0.84rem;
  columns: 2 22rem;
  column-gap: 2rem;
  padding-left: 1.2rem;
}
.stage-list li {
  break-inside: avoid;
  margin-bottom: 0.2rem;
}
.stage-list button {
  font: inherit;
  color: var(--link);
  background: none;
  border: 0;
  padding: 0.1rem 0;
  cursor: pointer;
  text-align: left;
  text-decoration: underline;
  text-underline-offset: 0.15em;
}

/* ---------- Figure 3: three views ---------- */
.three-views {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 13rem;
  grid-template-areas:
    'wave zoom'
    'spec spectrum';
  gap: 0.3rem 0.8rem;
}
.three-views .tv-zoom {
  grid-area: zoom;
}
.three-views .tv-wave {
  grid-area: wave;
}
.three-views .tv-spec {
  grid-area: spec;
}
.three-views .tv-spectrum {
  grid-area: spectrum;
}
@media (max-width: 760px) {
  .three-views {
    grid-template-columns: minmax(0, 1fr);
    grid-template-areas: 'wave' 'zoom' 'spec' 'spectrum';
  }
}

/* ---------- Figure 4: lab pipeline ---------- */
.pipeline-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  margin: 0.4rem 0 0.9rem;
  padding: 0;
  list-style: none;
}
.pipeline-nav button {
  font-family: var(--sans);
  font-size: 0.78rem;
  color: var(--ink-2);
  background: #151514;
  border: 1px solid #3c3c38;
  border-radius: 99px;
  padding: 0.3rem 0.7rem;
  min-height: 2.2rem;
  cursor: pointer;
}
.pipeline-nav button[aria-current='step'] {
  background: var(--accent);
  color: #161208;
  border-color: var(--accent);
  font-weight: 650;
}
.pipeline-nav li:not(:last-child)::after {
  content: '→';
  color: var(--ink-3);
  margin: 0 0.15rem 0 0.25rem;
}
.step {
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.75rem 0.9rem;
  margin-bottom: 0.7rem;
  background: #161615;
  transition: opacity 0.2s;
}
.step.is-future {
  opacity: 0.35;
}
.step.is-current {
  border-color: var(--accent);
}
.step h4 {
  margin: 0 0 0.4rem;
  font-size: 0.9rem;
  color: var(--ink);
  display: flex;
  align-items: baseline;
  gap: 0.5rem;
}
.step h4 .n {
  font-family: var(--mono);
  color: var(--ink-3);
  font-weight: 400;
}
.step p {
  margin: 0.2rem 0 0.5rem;
  color: var(--ink-2);
  font-size: 0.85rem;
}
.chips {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  max-height: 15rem;
  overflow-y: auto;
  padding: 0.1rem;
}
.chip {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--ink);
  background: #1f1f1d;
  border: 1px solid #3c3c38;
  border-radius: 6px;
  padding: 0.25rem 0.45rem;
  cursor: pointer;
  text-align: center;
  line-height: 1.25;
  min-height: 2rem;
}
.chip small {
  display: block;
  color: var(--ink-3);
  font-size: 0.68rem;
}
.chip.is-selected {
  outline: 2px solid var(--focus);
  outline-offset: 1px;
}
.chip.is-playing {
  background: #34342f;
  border-color: var(--ink-2);
}
.bitrow {
  display: flex;
  flex-wrap: wrap;
  gap: 2px;
  font-family: var(--mono);
  font-size: 0.78rem;
}
.bit {
  width: 1.45rem;
  height: 1.85rem;
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  border-radius: 3px;
  background: #1f1f1d;
  color: var(--ink);
  border: 0;
  cursor: pointer;
  padding: 0;
  font: inherit;
  position: relative;
}
.bit::after {
  content: '';
  position: absolute;
  left: 3px;
  right: 3px;
  bottom: 2px;
  height: 3px;
  border-radius: 2px;
  background: var(--bc, transparent);
}
.bit.b0 {
  --bc: var(--s1);
}
.bit.b1 {
  --bc: var(--s2);
}
.bit.frame {
  color: var(--ink-3);
  --bc: #55554f;
}
.bit.idle {
  color: var(--ink-3);
  opacity: 0.6;
  --bc: transparent;
}
.bit.is-selected {
  outline: 2px solid var(--focus);
}
.bit.is-playing {
  background: #3a3a35;
}
.bit.err {
  background: rgba(208, 59, 59, 0.28);
  text-decoration: line-through;
}
.byte-group {
  display: inline-flex;
  gap: 2px;
  padding: 2px;
  border-radius: 4px;
  margin-right: 4px;
}
.byte-group.is-selected {
  background: rgba(255, 212, 121, 0.14);
}
.bit-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  font-size: 0.75rem;
  color: var(--ink-2);
  margin: 0.4rem 0;
}
.bit-legend span::before {
  content: '';
  display: inline-block;
  width: 0.9rem;
  height: 3px;
  border-radius: 2px;
  background: var(--c);
  margin-right: 0.35rem;
  vertical-align: middle;
}
.recovered {
  font-family: var(--mono);
  font-size: 1.15rem;
  color: var(--ink);
  background: #101010;
  border-radius: 6px;
  padding: 0.6rem 0.75rem;
  min-height: 2.6rem;
  word-break: break-all;
}
.recovered .bad {
  background: rgba(208, 59, 59, 0.35);
  border-radius: 2px;
  text-decoration: underline wavy var(--critical);
}
.recovered .noise {
  color: var(--ink-3);
  background: rgba(255, 255, 255, 0.06);
  border-radius: 2px;
}
.status {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.85rem;
  padding: 0.2rem 0.6rem;
  border-radius: 99px;
  border: 1px solid var(--line);
}
.status.good::before {
  content: '✓';
  color: var(--good);
  font-weight: 700;
}
.status.bad::before {
  content: '✕';
  color: var(--critical);
  font-weight: 700;
}
.status.info::before {
  content: 'ℹ';
  color: var(--ink-2);
}
.receiver-log {
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--ink-2);
  max-height: 9rem;
  overflow-y: auto;
  background: #101010;
  border-radius: 6px;
  padding: 0.4rem 0.6rem;
  margin: 0.4rem 0 0;
}

/* stats tiles */
.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(9.5rem, 1fr));
  gap: 0.6rem;
  margin: 0.8rem 0;
}
.stat {
  background: #151514;
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 0.55rem 0.7rem;
}
.stat .k {
  font-size: 0.72rem;
  color: var(--ink-3);
  display: block;
}
.stat .v {
  font-size: 1.2rem;
  color: var(--ink);
  font-weight: 600;
  display: block;
}
.stat .s {
  font-size: 0.72rem;
  color: var(--ink-2);
  display: block;
  margin-top: 0.1rem;
}

.two-col {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(19rem, 1fr));
  gap: 0.8rem 1.2rem;
}

.table-wrap {
  overflow-x: auto;
  margin: 1.5rem 0;
}
.data-table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--sans);
  font-size: 0.85rem;
  font-variant-numeric: tabular-nums;
}
.data-table caption {
  text-align: left;
  font-weight: 600;
  color: var(--ink);
  padding-bottom: 0.5rem;
}
.data-table th,
.data-table td {
  text-align: left;
  padding: 0.5rem 0.6rem;
  border-bottom: 1px solid var(--grid);
  vertical-align: top;
}
.data-table thead th {
  color: var(--ink-3);
  font-weight: 600;
  font-size: 0.78rem;
}
.data-table tbody th {
  color: var(--ink);
  font-weight: 600;
}
.data-table td.num {
  text-align: right;
}
.fig .data-table {
  font-size: 0.8rem;
}

/* Figure 9: browser */
.browser {
  border: 1px solid #555;
  border-radius: 6px;
  overflow: hidden;
  background: #c0c0c0;
  color: #000;
  font-family: Arial, Helvetica, sans-serif;
}
.browser-chrome {
  background: linear-gradient(#d4d0c8, #c0bcb4);
  border-bottom: 1px solid #808080;
  padding: 0.3rem 0.5rem;
  display: flex;
  gap: 0.5rem;
  align-items: center;
  font-size: 0.78rem;
}
.browser-title {
  background: linear-gradient(90deg, #0a246a, #3a6ea5);
  color: #fff;
  font-size: 0.78rem;
  font-weight: 700;
  padding: 0.2rem 0.5rem;
  display: flex;
  justify-content: space-between;
}
.browser-url {
  flex: 1;
  background: #fff;
  border: 2px inset #e0e0e0;
  padding: 0.12rem 0.4rem;
  font-family: Arial, sans-serif;
  font-size: 0.78rem;
  overflow: hidden;
  white-space: nowrap;
  text-overflow: ellipsis;
  color: #000;
}
.throbber {
  width: 1.8rem;
  height: 1.8rem;
  border: 2px inset #e0e0e0;
  background: #000 radial-gradient(circle at 50% 60%, #6fa8ff 0 22%, transparent 24%);
  flex: 0 0 auto;
}
.browser.is-loading .throbber {
  background: #000 radial-gradient(circle at 50% 60%, #ffd16f 0 30%, transparent 32%);
}
.browser-view {
  height: 30rem;
  overflow-y: auto;
  padding: 0.6rem 1rem 1rem;
  font-family: 'Times New Roman', Times, serif;
  font-size: 16px;
  line-height: 1.3;
  color: #000;
  background-color: #c0c0c0;
}
.browser-view h1 {
  font-family: 'Times New Roman', Times, serif;
  color: #000;
  font-size: 1.9em;
  font-weight: bold;
  letter-spacing: 0;
  margin: 0.4em 0;
  max-width: none;
}
.browser-view h2 {
  font-family: 'Times New Roman', Times, serif;
  color: #000;
  font-size: 1.4em;
  font-weight: bold;
  letter-spacing: 0;
  margin: 0.5em 0;
}
.browser-view p,
.browser-view li {
  max-width: none;
  margin: 0.5em 0;
}
.browser-view a {
  color: #0000ee;
}
.browser-view hr {
  border: 0;
  border-top: 2px groove #f0f0f0;
}
.browser-view .center {
  text-align: center;
}
.browser-view canvas.img {
  display: inline-block;
  vertical-align: middle;
  image-rendering: pixelated;
}
.browser-view .img-wrap {
  display: inline-block;
  position: relative;
  vertical-align: middle;
  max-width: 100%;
}
.browser-view .img-wrap canvas {
  max-width: 100%;
  height: auto;
}
.browser-view .placeholder {
  position: absolute;
  inset: 0;
  border: 1px solid #808080;
  background: #c0c0c0;
  font: 11px Arial, sans-serif;
  color: #333;
  padding: 2px 4px;
  overflow: hidden;
}
.browser-view .placeholder::before {
  content: '🖼 ';
}
.browser-view .caret {
  display: inline-block;
  width: 0.5em;
  height: 1em;
  background: #000;
  vertical-align: text-bottom;
  opacity: 0.4;
}
.browser-status {
  background: #c0c0c0;
  border-top: 1px solid #808080;
  padding: 0.2rem 0.5rem;
  font-family: Arial, sans-serif;
  font-size: 0.75rem;
  color: #000;
  display: flex;
  justify-content: space-between;
  gap: 1rem;
}
.progressbar {
  width: 8rem;
  height: 0.8rem;
  border: 2px inset #e0e0e0;
  background: #fff;
}
.progressbar i {
  display: block;
  height: 100%;
  background: #0a246a;
  width: 0;
}

.waterfall {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.78rem;
  font-variant-numeric: tabular-nums;
}
.waterfall th,
.waterfall td {
  padding: 0.3rem 0.4rem;
  border-bottom: 1px solid var(--grid);
  text-align: left;
  white-space: nowrap;
}
.waterfall td.bar-cell {
  width: 55%;
  min-width: 12rem;
  padding: 0.2rem 0;
}
.waterfall svg {
  display: block;
  width: 100%;
  height: 22px;
}
.wf-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  font-size: 0.75rem;
  color: var(--ink-2);
  margin: 0.5rem 0;
}
.wf-legend span::before {
  content: '';
  display: inline-block;
  width: 0.8rem;
  height: 0.8rem;
  border-radius: 2px;
  background: var(--c);
  margin-right: 0.35rem;
  vertical-align: -0.12rem;
}

/* constellation / charts */
.const-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(16rem, 22rem);
  gap: 1rem;
  align-items: start;
}
@media (max-width: 820px) {
  .const-grid {
    grid-template-columns: minmax(0, 1fr);
  }
}
.const-pair {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(15rem, 1fr));
  gap: 0.8rem;
}

/* glossary & sources */
.glossary dt {
  font-family: var(--sans);
  font-weight: 650;
  color: var(--ink);
  margin-top: 1rem;
}
.glossary dd {
  margin: 0.2rem 0 0;
  color: var(--ink-2);
  font-size: 1rem;
}
.glossary dt:target,
.sources li:target {
  background: rgba(255, 212, 121, 0.12);
  border-radius: 4px;
}
.sources {
  font-family: var(--sans);
  font-size: 0.86rem;
  color: var(--ink-2);
  padding-left: 2rem;
}
.sources li {
  margin-bottom: 0.6rem;
}
.sources cite {
  font-style: italic;
  color: var(--ink);
}
.site-footer {
  margin-top: 3rem;
  padding: 2rem 1.25rem 3rem;
  font-family: var(--sans);
  font-size: 0.82rem;
  color: var(--ink-3);
  text-align: center;
}
.site-footer p {
  max-width: 48rem;
  margin: 0.5rem auto;
}
.site-footer::before {
  content: '';
  display: block;
  width: 2rem;
  height: 1.1rem;
  margin: 0 auto 1.25rem;
  background: var(--ink-3);
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 32 18'%3E%3Cpath d='M1 9 Q4 1 7 9 T13 9 T19 9 T25 9 T31 9' stroke='black' stroke-width='2.4' fill='none'/%3E%3C/svg%3E") center/contain no-repeat;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 32 18'%3E%3Cpath d='M1 9 Q4 1 7 9 T13 9 T19 9 T25 9 T31 9' stroke='black' stroke-width='2.4' fill='none'/%3E%3C/svg%3E") center/contain no-repeat;
}

/* ---------- small screens ---------- */
@media (max-width: 640px) {
  body {
    font-size: 1.0625rem;
  }
  .masthead-inner {
    gap: 0.5rem;
    padding: 0.3rem 0.6rem;
    flex-wrap: wrap;
  }
  .brand {
    font-size: 0.8rem;
  }
  .now-playing {
    display: none;
  }
  .vol input {
    width: 4.5rem;
  }
  .fig-body {
    padding: 0.7rem;
  }
  .timeline {
    --label-w: 4.6rem;
  }
  .tl-label {
    font-size: 0.66rem;
  }
  .tl-stage-label {
    display: none;
  }
  .legend-kinds div {
    flex-direction: column;
    gap: 0.2rem;
  }
  .legend-kinds dt {
    flex: none;
  }
  .ctl-range {
    max-width: none;
  }
  .browser-view {
    height: 24rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    transition: none !important;
    animation: none !important;
  }
}

@media (forced-colors: active) {
  .tl-stage,
  .badge,
  .btn {
    border: 1px solid CanvasText;
  }
}

.linkish {
  font: inherit;
  color: var(--link);
  background: none;
  border: 0;
  padding: 0;
  cursor: pointer;
  text-decoration: underline;
  text-underline-offset: 0.15em;
  text-align: left;
}
.equation {
  font-family: var(--mono);
  font-size: 1.05rem;
  color: var(--ink);
  margin: 0.3rem 0;
  font-variant-numeric: tabular-nums;
}

/* Figure 7 */
.bits-compare {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem 0.8rem;
  max-height: 16rem;
  overflow-y: auto;
  padding: 0.2rem;
}
.byte-cmp {
  display: inline-flex;
  flex-direction: column;
  gap: 2px;
}
.byte-cmp .bit {
  width: 1.2rem;
  height: 1.45rem;
  cursor: default;
}
.byte-cmp-label {
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--ink-3);
}
.byte-cmp-label.bad {
  color: var(--ink);
}
.byte-cmp-label.bad::before {
  content: '✕ ';
  color: var(--critical);
}
.cap-scale {
  position: relative;
  height: 3.6rem;
  margin: 0.5rem 0 1.8rem;
  background: #121211;
  border-radius: 4px;
}
.cap-bar {
  position: absolute;
  left: 0;
  top: 0.4rem;
  height: 1.1rem;
  background: var(--s1);
  border-radius: 0 4px 4px 0;
}
.cap-mark {
  position: absolute;
  top: 0;
  bottom: 0;
  border-left: 1px solid var(--ink-3);
}
.cap-mark span {
  position: absolute;
  top: 1.75rem;
  left: 0.25rem;
  font-family: var(--sans);
  font-size: 0.68rem;
  color: var(--ink-2);
  white-space: nowrap;
  transform: translateX(-10%);
}
.cap-mark:nth-child(odd) span {
  top: 2.65rem;
}
.cap-mark.right span {
  left: auto;
  right: 0.25rem;
  transform: none;
}

/* Figure 2: path of a call */
.path-diagram {
  display: flex;
  flex-wrap: wrap;
  align-items: stretch;
  gap: 0.4rem;
  margin: 0.9rem 0 0.5rem;
}
.pd-node {
  flex: 1 1 7rem;
  min-width: 7rem;
  max-width: 10.5rem;
  background: #151514;
  border: 1px solid #3c3c38;
  border-radius: 8px;
  padding: 0.5rem 0.6rem;
  display: flex;
  flex-direction: column;
  gap: 0.15rem;
}
.pd-node strong {
  color: var(--ink);
  font-size: 0.85rem;
}
.pd-node span {
  color: var(--ink-3);
  font-size: 0.74rem;
}
.pd-node.conv {
  border-color: var(--accent);
}
.pd-link {
  flex: 1 1 5rem;
  min-width: 4.5rem;
  display: flex;
  flex-direction: column;
  justify-content: center;
  gap: 0.25rem;
}
.pd-arrow {
  display: block;
  height: 12px;
  position: relative;
}
.pd-link.digital .pd-arrow {
  background: linear-gradient(var(--ink-2), var(--ink-2)) center/100% 2px no-repeat;
}
.pd-link.analog .pd-arrow {
  background: var(--s3);
  -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 12'%3E%3Cpath d='M0 6 Q3 0 6 6 T12 6 T18 6 T24 6' stroke='black' stroke-width='2' fill='none'/%3E%3C/svg%3E") left center/24px 12px repeat-x;
  mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 12'%3E%3Cpath d='M0 6 Q3 0 6 6 T12 6 T18 6 T24 6' stroke='black' stroke-width='2' fill='none'/%3E%3C/svg%3E") left center/24px 12px repeat-x;
}
.pd-label {
  font-size: 0.7rem;
  color: var(--ink-2);
  text-align: center;
  line-height: 1.25;
}
@media (max-width: 640px) {
  .path-diagram {
    flex-direction: column;
  }
  .pd-node {
    max-width: none;
  }
  .pd-link {
    flex-direction: row;
    align-items: center;
    min-height: 2.4rem;
  }
  .pd-arrow {
    width: 12px;
    height: 2.2rem;
    flex: 0 0 auto;
    margin-left: 1.5rem;
  }
  .pd-link.digital .pd-arrow {
    background: linear-gradient(var(--ink-2), var(--ink-2)) center/2px 100% no-repeat;
  }
  .pd-link.analog .pd-arrow {
    transform: rotate(90deg);
    width: 2.2rem;
    height: 12px;
    margin-left: 0.6rem;
  }
  .pd-label {
    text-align: left;
    margin-left: 0.6rem;
  }
}

/* Figure 8: envelopes */
.env-bar {
  display: flex;
  height: 2.4rem;
  gap: 2px;
  margin: 0.9rem 0 0.4rem;
  border-radius: 4px;
  overflow: hidden;
}
.env-seg {
  min-width: 3px;
  display: flex;
  align-items: center;
  padding: 0 0.5rem;
  overflow: hidden;
}
.env-seg span {
  font-size: 0.74rem;
  font-weight: 600;
  color: #fff;
  white-space: nowrap;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.6);
}
.swatch {
  display: inline-block;
  width: 0.7rem;
  height: 0.7rem;
  border-radius: 2px;
  margin-right: 0.4rem;
  vertical-align: -0.05rem;
}

/* Figure 9: line busy/idle */
.util-bar {
  display: flex;
  height: 1.4rem;
  gap: 2px;
  border-radius: 4px;
  overflow: hidden;
  background: transparent;
}
.util-busy {
  background: var(--s1);
  min-width: 1px;
}
.util-idle {
  min-width: 1px;
  background: repeating-linear-gradient(135deg, #2a2a27 0 5px, #1f1f1d 5px 8px);
}