/* A single stable frame for all three demonstrations. Content never fades on a switch. */
.demo-main { padding-block: 38px 48px; }
.demo-intro { display: flex; align-items: end; justify-content: space-between; gap: 20px; padding-bottom: 26px; }
.demo-intro h1 { font: 34px/1.5 var(--serif); }
.demo-intro p { margin-top: 8px; font-size: 15px; color: var(--muted); }
.demo-intro .demo-overall-disclosure { font-size: 12px; margin-top: 10px; }
.demo-stage { min-height: 550px; }
.demo-modes { position: sticky; top: 73px; z-index: 5; display: flex; gap: 8px; padding-block: 8px; margin-bottom: 26px; border-block: 1px solid var(--line); background: var(--paper); }
.demo-mode-tab { min-width: 100px; min-height: 44px; padding: 10px 24px; background: transparent; border: 1px solid transparent; font-size: 14px; }
.demo-mode-tab[aria-selected="true"] { background: var(--sage); color: var(--green); border-color: var(--line); }
.demo-mode-tab:hover { color: var(--green); }
.demo-panel { margin: 0; scroll-margin-top: 155px; }
.demo-panel[hidden] { display: none !important; }
.demo-panel-heading { display: flex; align-items: baseline; justify-content: space-between; gap: 24px; margin-bottom: 22px; }
.demo-panel-heading h2 { font: 26px/1.5 var(--serif); }
.demo-panel-heading p { max-width: 42ch; font-size: 13px; color: var(--muted); }
.demo-noscript { margin-bottom: 30px; font-size: 14px; color: var(--muted); }
.demo-modes[hidden] ~ .demo-panel { margin-bottom: 44px; }
.demo-source { display: block; font-size: 12px; color: var(--green); margin-bottom: 12px; }
.experience-copy .demo-disclosure { margin-top: 12px; font-size: 12px; }
.demo-footer { display: flex; align-items: center; flex-wrap: wrap; gap: 12px 30px; }
.demo-footer nav { display: flex; flex-wrap: wrap; gap: 24px; margin-left: auto; font-size: 13px; }
.demo-footer nav a { min-height: 44px; display: inline-flex; gap: 10px; align-items: center; }
.demo-footer p { width: 100%; color: var(--muted); font-size: 12px; }
/* Only the signal display is a dark window; the measurements stay on paper. */
.signal-workbench { padding: 24px 28px 28px; background: var(--green); color: var(--paper); }
.signal-tabs { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); border-bottom: 1px solid rgb(244 240 231 / 25%); }
.signal-tabs button { display: flex; align-items: center; justify-content: center; gap: 12px; min-height: 48px; padding: 10px 16px; background: transparent; color: var(--paper); border: 1px solid transparent; border-bottom: 0; }
.signal-tabs button[aria-selected="true"] { color: var(--ink); background: var(--sage); }
.signal-tabs button:hover:not([aria-selected="true"]) { border-color: rgb(244 240 231 / 45%); }
.signal-tabs b { font-family: var(--mono); font-size: 16px; font-weight: 400; }
.signal-tabs button > span { font-size: var(--step-small); white-space: nowrap; }
.signal-panel { min-width: 0; }
.signal-chart { padding: 24px 0 20px; border-bottom: 1px solid rgb(244 240 231 / 25%); }
.chart-header, .chart-footer { display: flex; align-items: center; flex-wrap: wrap; justify-content: space-between; gap: 8px 20px; font-size: var(--step-small); }
#signal-source-label { display: inline-flex; align-items: center; gap: 8px; }
#signal-source-label::before { content: ""; width: 5px; height: 5px; background: #c5d8bb; border-radius: 50%; }
.waveform { color: #c5d8bb; width: 100%; height: 178px; margin-block: 16px; overflow: hidden; }
.chart-footer { color: #d2ded3; }
.signal-description { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.4fr); column-gap: 48px; row-gap: 12px; margin-top: 24px; }
.signal-description h3 { font-size: 20px; line-height: 1.5; }
.signal-description p { max-width: 590px; font-size: 15px; line-height: 1.85; }
.signal-topics { grid-column: 2; display: flex; flex-wrap: wrap; gap: 8px 20px; color: #d2ded3; font-size: var(--step-small); }
.metrics-preview { color: var(--ink); }
.metrics-heading { display: flex; align-items: start; justify-content: space-between; gap: 24px; }
.metrics-heading h2 { font-family: var(--serif); font-size: 26px; line-height: 1.5; }
.metrics-heading p { margin-top: 10px; max-width: 710px; color: var(--muted); font-size: 14px; }
.metrics-source { color: var(--green); font-size: var(--step-small); white-space: nowrap; padding: 3px 0 3px 12px; border-left: 2px solid var(--green); }
.metrics-toolbar { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-top: 24px; padding-bottom: 20px; border-bottom: 1px solid var(--line); }
.metrics-controls { display: flex; align-items: center; gap: 10px; }
.metrics-controls .button { min-width: 118px; }
.metrics-reset { min-width: 64px; min-height: 48px; padding: 11px 14px; border: 1px solid var(--line); background: transparent; font-size: 14px; }
.metrics-reset:hover { background: var(--paper); }
.metrics-playback { display: flex; gap: 4px 20px; flex-wrap: wrap; justify-content: end; font-size: 12px; color: var(--muted); font-variant-numeric: tabular-nums; }
.metric-readouts { display: grid; grid-template-columns: minmax(0, 1.2fr) repeat(2, minmax(0, 1fr)); column-gap: 12px; margin: 24px 0 20px; }
.metric-readouts > div { min-width: 0; padding-inline: 16px; }
.metric-readouts > div:nth-child(-n + 2) { grid-area: 1 / 1; width: 50%; }
.metric-readouts > div:nth-child(2) { justify-self: end; }
.metric-readouts > div:nth-child(3) { grid-area: 1 / 2; }
.metric-readouts > div:nth-child(4) { grid-area: 1 / 3; }
.metric-readouts dt { font-size: 12px; color: var(--muted); }
.metric-readouts dd { display: flex; flex-wrap: wrap; gap: 3px 8px; align-items: baseline; margin: 7px 0 0; font-family: var(--mono); font-size: 30px; line-height: 1.3; font-variant-numeric: tabular-nums; }
.metrics-playback, .metric-range, .metric-axis { font-family: var(--mono); }
.metric-unit { font-size: 12px; white-space: nowrap; }
.metrics-charts { display: grid; grid-template-columns: minmax(0, 1.2fr) repeat(2, minmax(0, 1fr)); gap: 12px; }
.metric-chart { min-width: 0; padding: 16px; background: var(--surface); border-top: 1px solid var(--line); }
.metric-chart figcaption { font-size: 12px; }
.metric-plot { display: flex; gap: 8px; margin-top: 12px; }
.metric-range { display: flex; flex-direction: column; justify-content: space-between; min-width: 22px; padding-block: 10.5px; font-size: 11px; color: var(--muted); line-height: 1; font-variant-numeric: tabular-nums; }
.metric-plot svg { width: 100%; min-width: 0; height: 160px; overflow: hidden; }
.metric-plot path { fill: none; stroke: var(--green); stroke-width: 2.5; vector-effect: non-scaling-stroke; stroke-linejoin: round; stroke-linecap: round; }
/* These guides share the curve's 16–144 plotting interval. */
.metric-plot .metric-guides path { stroke: var(--ink); stroke-opacity: .14; stroke-width: 1; stroke-linecap: butt; }
#metric-edr-path { stroke: var(--copper); stroke-dasharray: 5 6; }
.metric-axis, .metric-legend { display: flex; justify-content: space-between; gap: 8px 12px; font-size: 11px; color: var(--muted); }
.metric-axis { margin-left: 30px; }
.metric-legend { margin-top: 10px; flex-wrap: wrap; }
.metrics-note { margin-top: 18px; max-width: none; font-size: 12px; color: var(--muted); }
.metrics-preview noscript p { padding-top: 12px; border-top: 1px solid var(--line); }

.experience-panel { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1fr); gap: 64px; align-items: center; }
.experience-copy h2 { font-family: var(--serif); font-size: var(--step-head); line-height: 1.5; letter-spacing: 0; margin-bottom: 20px; }
.experience-copy > p { max-width: 400px; color: var(--muted); }
.breathing-pace { display: flex; flex-direction: column; gap: 8px; margin-top: 24px; max-width: 340px; font-size: var(--step-small); }
.breathing-pace select { width: 100%; min-height: 48px; padding: 10px 12px; border: 1px solid var(--line); border-radius: 0; background: var(--paper); color: var(--ink); font-size: 14px; }
.demo-controls { display: flex; gap: 12px; align-items: center; margin-top: 20px; }
.demo-controls .button { gap: 14px; min-width: 160px; }
.reset-button { width: 48px; height: 48px; border: 1px solid var(--line); background: transparent; font-size: 22px; line-height: 1; }
.reset-button:hover { background: var(--surface); }
.breathing-visual { width: 100%; max-width: 372px; justify-self: center; }
.orbit { position: relative; aspect-ratio: 1; width: 100%; display: flex; align-items: center; justify-content: center; isolation: isolate; }
.orbit-ring, .breath-core { position: absolute; border-radius: 50%; }
.orbit-ring-outer { inset: 2%; border: 1px solid var(--line); }
.orbit-ring-middle { width: 76%; height: 76%; border: 1px solid var(--copper); }
.breath-core { width: 57%; height: 57%; background: var(--sage); border: 1px solid #c8d3c4; }
.breathing-instruction { position: relative; z-index: 2; display: flex; flex-direction: column; align-items: center; gap: 8px; text-align: center; }
.breathing-instruction strong { font-size: 20px; font-weight: 500; }
.breathing-instruction > span { font-size: 12px; color: var(--muted); }
.demo-caption { display: flex; justify-content: space-between; gap: 8px 12px; font-size: 12px; color: var(--muted); margin-top: 12px; padding-top: 12px; border-top: 1px solid var(--line); }


@media (max-width: 1100px) {
  .experience-panel { gap: 40px; }
  .metric-readouts { grid-template-columns: repeat(4, minmax(0, 1fr)); column-gap: 12px; }
  .metric-readouts > div:nth-child(n) { grid-area: auto; justify-self: stretch; width: auto; padding-inline: 0; }
  .metric-readouts dd { font-size: 28px; }
  .metrics-charts { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .metric-chart-heart { grid-column: 1 / -1; }
}
@media (max-width: 760px) {
  .demo-main { padding-block: 26px 32px; }
  .demo-intro { flex-direction: column; align-items: start; gap: 10px; padding-bottom: 20px; }
  .demo-intro h1 { font-size: 28px; }
  .demo-intro p { font-size: 14px; }
  .demo-intro .demo-overall-disclosure { font-size: 11px; }
  .demo-stage { min-height: 540px; }
  .demo-modes { top: 72px; margin-bottom: 22px; gap: 4px; }
  .demo-mode-tab { flex: 1; min-width: 0; padding-inline: 12px; }
  .demo-panel-heading { flex-direction: column; align-items: start; gap: 8px; margin-bottom: 18px; }
  .demo-panel-heading h2, .metrics-heading h2 { font-size: 23px; }
  .demo-panel-heading p { font-size: 12px; }
  .signal-workbench { padding: 16px 16px 22px; }
  .signal-tabs button { flex-direction: column; gap: 0; min-height: 60px; padding: 8px 4px; }
  .signal-tabs b { font-size: 15px; }
  .signal-tabs button > span { font-size: 12px; }
  .signal-chart { padding-block: 20px 16px; }
  .chart-header, .chart-footer { font-size: 11px; gap: 6px 10px; }
  .waveform { height: 145px; margin-block: 16px; }
  .signal-description { grid-template-columns: 1fr; gap: 12px; margin-top: 20px; }
  .signal-description h3 { font-size: 19px; }
  .signal-description p { font-size: 14px; }
  .signal-topics { grid-column: 1; gap: 8px 16px; font-size: 12px; }
  .metrics-heading { gap: 12px; }
  .metrics-heading p { font-size: 12px; line-height: 1.8; }
  .metrics-source { font-size: 11px; }
  .metrics-toolbar { flex-direction: column; align-items: start; gap: 14px; margin-top: 20px; padding-bottom: 18px; }
  .metrics-playback { justify-content: start; max-width: none; font-size: 11px; }
  .metric-readouts { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px 12px; margin-block: 22px; }
  .metric-readouts dt { font-size: 11px; }
  .metric-readouts dd { margin-top: 6px; font-size: 28px; gap: 2px 6px; }
  .metrics-charts { grid-template-columns: minmax(0, 1fr); gap: 12px; }
  .metric-chart { padding: 16px 12px; }
  .metric-chart-heart { grid-column: auto; }
  .metric-chart figcaption { font-size: 12px; }
  .metrics-note { font-size: 11px; }
  .experience-panel { grid-template-columns: 1fr; gap: 28px; }
  .experience-copy h2 br { display: none; }
  .experience-copy h2 { margin-bottom: 14px; font-size: 23px; }
  .experience-copy > p { max-width: 540px; font-size: 14px; }
  .experience-copy .demo-disclosure { font-size: 12px; }
  .breathing-pace { margin-top: 20px; max-width: 360px; }
  .breathing-visual { max-width: 310px; }
  .breathing-instruction strong { font-size: 19px; }
  .demo-caption { flex-wrap: wrap; gap: 6px 12px; font-size: 11px; }
  .demo-footer { gap: 10px; }
  .demo-footer nav { gap: 16px; }
}
@media (max-width: 370px) {
  .demo-intro h1 { font-size: 26px; }
  .signal-workbench { padding-inline: 12px; }
  .chart-header { align-items: start; }
  .chart-header > span:first-child { max-width: 144px; }
  .metrics-heading { flex-direction: column; }
  .breathing-instruction strong { font-size: 18px; }
  .demo-footer nav { width: 100%; margin: 0; }
}