:root {
  color-scheme: dark;
  --bg: #07111f;
  --bg-deep: #040a13;
  --surface: #0a1727;
  --panel: rgba(16, 30, 51, 0.94);
  --panel-solid: #101e33;
  --panel-soft: rgba(25, 43, 70, 0.72);
  --line: rgba(157, 177, 217, 0.18);
  --line-strong: rgba(157, 177, 217, 0.34);
  --text: #f4f7ff;
  --muted: #aebbd3;
  --quiet: #7f90ad;
  --blue: #6ea8ff;
  --cyan: #48d7e8;
  --purple: #a98bff;
  --orange: #ffb05f;
  --pink: #ff7ca8;
  --green: #62dfb3;
  --danger: #ff7a85;
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.3);
  --radius: 20px;
  --radius-sm: 12px;
  font-family: Inter, ui-sans-serif, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  min-width: 320px;
  margin: 0;
  background:
    radial-gradient(circle at 11% -10%, rgba(72, 215, 232, 0.13), transparent 29rem),
    radial-gradient(circle at 88% 5%, rgba(169, 139, 255, 0.12), transparent 31rem),
    linear-gradient(180deg, var(--bg) 0%, var(--bg-deep) 100%);
  color: var(--text);
}

body::before {
  position: fixed;
  z-index: -1;
  inset: 0;
  background-image:
    linear-gradient(rgba(110, 168, 255, 0.018) 1px, transparent 1px),
    linear-gradient(90deg, rgba(110, 168, 255, 0.018) 1px, transparent 1px);
  background-size: 40px 40px;
  content: "";
  pointer-events: none;
}

button, input { font: inherit; }
button, a { -webkit-tap-highlight-color: transparent; }
button { color: inherit; }
a { color: inherit; }
button:focus-visible, a:focus-visible, input:focus-visible {
  outline: 3px solid rgba(72, 215, 232, 0.44);
  outline-offset: 3px;
}

.skip-link {
  position: fixed;
  z-index: 100;
  top: 10px;
  left: 10px;
  padding: 11px 15px;
  border-radius: 8px;
  background: var(--cyan);
  color: #06101d;
  font-size: 13px;
  font-weight: 800;
  text-decoration: none;
  transform: translateY(-160%);
}
.skip-link:focus { transform: translateY(0); }

.app-shell {
  width: min(1480px, calc(100% - 44px));
  margin: 0 auto;
  padding-bottom: 48px;
}

.topbar {
  position: sticky;
  z-index: 20;
  top: 0;
  display: flex;
  min-height: 92px;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  border-bottom: 1px solid var(--line);
  background: rgba(7, 17, 31, 0.86);
  backdrop-filter: blur(18px);
}

.brand, .footer-brand {
  display: inline-flex;
  align-items: center;
  gap: 14px;
  text-decoration: none;
}

.brand-mark {
  display: grid;
  flex: 0 0 42px;
  width: 42px;
  height: 42px;
  place-items: center;
  border: 1px solid rgba(72, 215, 232, 0.5);
  border-radius: 11px;
  background: linear-gradient(145deg, rgba(72, 215, 232, 0.2), rgba(110, 168, 255, 0.08));
  box-shadow: inset 0 0 22px rgba(72, 215, 232, 0.08), 0 0 24px rgba(72, 215, 232, 0.08);
  color: var(--cyan);
  font-size: 21px;
  font-weight: 900;
  letter-spacing: -0.07em;
}

.brand-copy { display: flex; flex-direction: column; line-height: 1.05; }
.brand-kicker {
  margin-bottom: 5px;
  color: var(--cyan);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 9px;
  font-weight: 800;
  letter-spacing: 0.17em;
  text-transform: uppercase;
}
.brand-copy strong { font-size: 17px; letter-spacing: -0.025em; }
.brand-copy small { margin-top: 5px; color: var(--quiet); font-size: 10px; }

.topbar-actions { display: flex; align-items: center; gap: 9px; }
.live-pill, .quiet-button, .status-chip, .model-badge, .slope-badge {
  border: 1px solid var(--line);
  border-radius: 999px;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}
.live-pill {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-height: 36px;
  padding: 0 13px;
  color: var(--green);
}
.live-pill i, .status-dot {
  display: inline-block;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--green);
  box-shadow: 0 0 0 5px rgba(98, 223, 179, 0.1), 0 0 14px rgba(98, 223, 179, 0.55);
}
.quiet-button {
  display: inline-flex;
  min-height: 36px;
  align-items: center;
  gap: 6px;
  padding: 0 13px;
  border-radius: 9px;
  background: rgba(25, 43, 70, 0.42);
  color: var(--muted);
  cursor: pointer;
  text-decoration: none;
  transition: 160ms ease;
}
.quiet-button:hover { border-color: var(--line-strong); background: var(--panel-soft); color: var(--text); }

.status-strip {
  display: flex;
  min-height: 40px;
  align-items: center;
  gap: 0;
  border-bottom: 1px solid var(--line);
  color: var(--quiet);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 9px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}
.status-strip > span {
  display: inline-flex;
  min-height: 18px;
  align-items: center;
  gap: 7px;
  padding: 0 18px;
  border-right: 1px solid var(--line);
}
.status-strip > span:first-child { padding-left: 0; }
.status-strip > span:last-child { border-right: 0; }
.status-strip b { color: var(--muted); font-weight: 700; }
.status-dot { width: 5px; height: 5px; box-shadow: none; }
.status-dot.flowing { background: var(--cyan); box-shadow: 0 0 10px rgba(72, 215, 232, 0.65); }
.status-dot.open { background: var(--danger); box-shadow: 0 0 10px rgba(255, 122, 133, 0.55); }

.section-tabs {
  display: flex;
  min-height: 53px;
  align-items: end;
  gap: 28px;
  border-bottom: 1px solid var(--line);
}
.section-tabs a {
  position: relative;
  padding: 0 2px 15px;
  color: var(--quiet);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.03em;
  text-decoration: none;
}
.section-tabs a:hover { color: var(--text); }
.section-tabs a.active { color: var(--cyan); }
.section-tabs a.active::after {
  position: absolute;
  right: 0;
  bottom: -1px;
  left: 0;
  height: 2px;
  background: var(--cyan);
  box-shadow: 0 0 12px rgba(72, 215, 232, 0.65);
  content: "";
}

main { padding-top: 42px; }
#circuit-bench, #graph-panel, #notebook, #theory { scroll-margin-top: 110px; }
.lab-intro {
  display: grid;
  grid-template-columns: minmax(0, 1.35fr) minmax(320px, 0.65fr);
  gap: 70px;
  align-items: end;
  padding: 0 2px 32px;
}
.eyebrow, .panel-index, .section-label, .component-tag, .component-hint {
  color: var(--cyan);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 9px;
  font-weight: 800;
  letter-spacing: 0.15em;
  text-transform: uppercase;
}
.lab-intro h1 {
  max-width: 800px;
  margin: 12px 0 0;
  font-size: clamp(34px, 4.7vw, 60px);
  font-weight: 680;
  letter-spacing: -0.055em;
  line-height: 1.02;
}
.lab-intro > p {
  max-width: 560px;
  margin: 0;
  color: var(--muted);
  font-size: 14px;
  line-height: 1.72;
}

.workspace {
  display: grid;
  grid-template-columns: minmax(0, 1.88fr) minmax(350px, 0.82fr);
  gap: 18px;
  align-items: start;
}
.visual-column { display: grid; min-width: 0; gap: 18px; }
.panel {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(145deg, rgba(16, 30, 51, 0.96), rgba(9, 23, 40, 0.96));
  box-shadow: var(--shadow);
}
.panel-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 28px;
  padding: 26px 28px 22px;
}
.panel-header.compact { padding-bottom: 20px; }
.panel-header h2, .observation-panel h2, .theory-card h2, .investigation-card h2 {
  margin: 7px 0 0;
  font-size: 21px;
  font-weight: 680;
  letter-spacing: -0.035em;
}
.panel-header p, .theory-card > p {
  max-width: 680px;
  margin: 7px 0 0;
  color: var(--quiet);
  font-size: 11px;
  line-height: 1.55;
}
.status-chip {
  display: inline-flex;
  flex: 0 0 auto;
  align-items: center;
  gap: 8px;
  padding: 9px 12px;
  color: var(--quiet);
}
.status-chip i { width: 7px; height: 7px; border-radius: 50%; background: var(--quiet); }
.status-chip.active { border-color: rgba(98, 223, 179, 0.28); color: var(--green); }
.status-chip.active i { background: var(--green); box-shadow: 0 0 13px rgba(98, 223, 179, 0.65); }

.measurement-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin: 0 28px 16px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 13px;
  background: rgba(4, 12, 23, 0.55);
}
.measurement {
  display: flex;
  min-width: 0;
  align-items: center;
  gap: 12px;
  padding: 14px 15px;
  border-right: 1px solid var(--line);
}
.measurement:last-child { border-right: 0; }
.measurement-symbol {
  display: grid;
  flex: 0 0 31px;
  width: 31px;
  height: 31px;
  place-items: center;
  border: 1px solid rgba(72, 215, 232, 0.3);
  border-radius: 8px;
  background: rgba(72, 215, 232, 0.08);
  color: var(--cyan);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 13px;
  font-weight: 800;
}
.resistance-measurement .measurement-symbol { border-color: rgba(255,176,95,.3); background: rgba(255,176,95,.08); color: var(--orange); }
.current-measurement .measurement-symbol { border-color: rgba(110,168,255,.3); background: rgba(110,168,255,.08); color: var(--blue); }
.power-measurement .measurement-symbol { border-color: rgba(169,139,255,.3); background: rgba(169,139,255,.08); color: var(--purple); }
.measurement > div { min-width: 0; }
.measurement small, .measurement strong { display: block; }
.measurement small {
  margin-bottom: 4px;
  overflow: hidden;
  color: var(--quiet);
  font-size: 8px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-overflow: ellipsis;
  text-transform: uppercase;
  white-space: nowrap;
}
.measurement strong {
  overflow: hidden;
  color: var(--text);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: clamp(15px, 1.6vw, 21px);
  font-weight: 650;
  letter-spacing: -0.04em;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.measurement em { margin-left: 4px; color: var(--quiet); font-size: 9px; font-style: normal; letter-spacing: 0; }

.apparatus-stage {
  margin: 0 14px;
  overflow: hidden;
  border: 1px solid rgba(110, 168, 255, 0.18);
  border-radius: 16px;
  background:
    radial-gradient(circle at 50% 37%, rgba(72, 215, 232, 0.08), transparent 32rem),
    linear-gradient(180deg, #071321, #050d18);
  box-shadow: inset 0 0 50px rgba(0, 0, 0, 0.36);
}
.stage-label, .stage-legend {
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: #637794;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 8px;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.stage-label { padding: 13px 16px 0; }
.circuit-svg { display: block; width: 100%; height: auto; }
.stage-grid-fill { fill: url(#stageGrid); }
.component-zones rect { fill: rgba(16, 30, 51, 0.62); stroke: rgba(157, 177, 217, 0.13); stroke-width: 1; }
.wires path, .wire, .direction path {
  fill: none;
  stroke: #56718e;
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 6;
}
.battery-long, .battery-short { stroke: var(--orange); stroke-linecap: round; stroke-width: 8; }
.polarity { fill: var(--orange); font-family: ui-monospace, monospace; font-size: 17px; font-weight: 800; }
.component-tag { fill: #6f87a6; font-size: 9px; }
.component-hint { fill: #607492; font-size: 8px; }
.component-reading { fill: #d8e6f6; font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace; font-size: 12px; font-weight: 700; }
.circuit-switch circle { fill: #0e2034; stroke: var(--orange); stroke-width: 4; }
#switchArm { stroke: var(--orange); stroke-linecap: round; stroke-width: 6; transition: 260ms ease; }
.meter > circle, .voltmeter > circle { fill: #091625; stroke: var(--cyan); stroke-width: 4; }
.meter .meter-inner, .voltmeter .meter-inner { fill: #0e2235; stroke: rgba(72, 215, 232, 0.2); stroke-width: 1; }
.meter-letter { fill: var(--cyan); font-family: ui-monospace, monospace; font-size: 25px; font-weight: 800; }
.resistor path { fill: none; stroke: var(--orange); stroke-linecap: round; stroke-linejoin: round; stroke-width: 7; }
.voltmeter > path { fill: none; stroke: rgba(72, 215, 232, 0.65); stroke-dasharray: 4 8; stroke-linecap: round; stroke-width: 2; }
.direction path { stroke: rgba(110, 168, 255, 0.38); stroke-width: 2; }
.electron-flow circle { fill: var(--cyan); stroke: #d5fbff; stroke-width: 1; }
.electron-flow.paused { display: none; }
.stage-legend {
  justify-content: flex-start;
  flex-wrap: wrap;
  gap: 20px;
  padding: 12px 16px 14px;
  border-top: 1px solid rgba(157, 177, 217, 0.1);
}
.stage-legend span { display: inline-flex; align-items: center; gap: 7px; }
.stage-legend i { display: inline-block; }
.legend-wire { width: 17px; height: 2px; background: #56718e; }
.legend-charge { width: 6px; height: 6px; border-radius: 50%; background: var(--cyan); box-shadow: 0 0 8px var(--cyan); }
.legend-meter { width: 10px; height: 10px; border: 2px solid var(--cyan); border-radius: 50%; }
.legend-load { width: 12px; height: 3px; background: var(--orange); }

.transport-bar {
  display: flex;
  min-height: 78px;
  align-items: center;
  gap: 18px;
  margin: 0 14px;
  padding: 13px 2px 16px;
}
.run-button {
  display: flex;
  min-width: 166px;
  align-items: center;
  gap: 11px;
  padding: 9px 12px;
  border: 1px solid rgba(72, 215, 232, 0.34);
  border-radius: 11px;
  background: linear-gradient(135deg, rgba(72, 215, 232, 0.16), rgba(110, 168, 255, 0.12));
  cursor: pointer;
  text-align: left;
}
.run-button:hover { border-color: var(--cyan); }
.run-icon {
  display: grid;
  width: 34px;
  height: 34px;
  place-items: center;
  border-radius: 8px;
  background: var(--cyan);
  box-shadow: 0 0 20px rgba(72, 215, 232, 0.25);
  color: #06101d;
  font-size: 19px;
  font-weight: 900;
}
.run-button small, .run-button strong, .transport-reading small, .transport-reading strong { display: block; }
.run-button small, .transport-reading small {
  color: var(--quiet);
  font-family: ui-monospace, monospace;
  font-size: 8px;
  letter-spacing: 0.09em;
  text-transform: uppercase;
}
.run-button strong { margin-top: 3px; color: var(--cyan); font-size: 12px; }
.run-button:not(.on) { border-color: rgba(255, 122, 133, 0.35); background: rgba(255, 122, 133, 0.08); }
.run-button:not(.on) .run-icon { background: var(--danger); box-shadow: 0 0 20px rgba(255,122,133,.2); }
.run-button:not(.on) strong { color: var(--danger); }
.transport-divider { width: 1px; height: 36px; background: var(--line); }
.transport-reading { min-width: 0; flex: 1; }
.transport-reading strong { margin-top: 5px; overflow: hidden; color: var(--muted); font-size: 11px; text-overflow: ellipsis; white-space: nowrap; }
.model-badge { padding: 8px 10px; color: var(--quiet); }

.control-panel {
  position: sticky;
  top: 110px;
  align-self: start;
}
.control-status { color: var(--cyan); font-size: 15px; text-shadow: 0 0 13px rgba(72, 215, 232, 0.85); }
.control-group, .preset-section, .derived-section {
  margin: 0 22px;
  padding: 24px 4px;
  border-top: 1px solid var(--line);
}
.control-label-row { display: flex; align-items: center; justify-content: space-between; gap: 18px; }
.control-label-row > div { min-width: 0; }
.control-label-row label { display: block; color: var(--text); font-size: 12px; font-weight: 700; }
.control-label-row small { display: block; margin-top: 4px; color: var(--quiet); font-size: 9px; }
.number-field {
  display: flex;
  flex: 0 0 auto;
  align-items: center;
  overflow: hidden;
  border: 1px solid var(--line-strong);
  border-radius: 9px;
  background: rgba(4, 12, 23, 0.62);
}
.number-field input {
  width: 72px;
  padding: 9px 3px 9px 9px;
  border: 0;
  outline: 0;
  background: transparent;
  color: var(--text);
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 12px;
  font-weight: 700;
  text-align: right;
}
.number-field span { padding: 0 9px 0 4px; color: var(--cyan); font-family: ui-monospace, monospace; font-size: 10px; font-weight: 700; }
.range {
  width: 100%;
  height: 5px;
  margin: 25px 0 0;
  border-radius: 100px;
  outline: none;
  appearance: none;
  background: linear-gradient(90deg, rgba(72,215,232,.88), rgba(110,168,255,.88));
  cursor: pointer;
}
.range::-webkit-slider-thumb {
  width: 20px;
  height: 20px;
  border: 4px solid #0e1d30;
  border-radius: 50%;
  appearance: none;
  background: var(--cyan);
  box-shadow: 0 0 0 1px rgba(72,215,232,.65), 0 0 18px rgba(72,215,232,.3);
}
.range::-moz-range-thumb {
  width: 13px;
  height: 13px;
  border: 4px solid #0e1d30;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 1px rgba(72,215,232,.65), 0 0 18px rgba(72,215,232,.3);
}
.resistance-range { background: linear-gradient(90deg, rgba(255,176,95,.95), rgba(169,139,255,.8)); }
.resistance-range::-webkit-slider-thumb { background: var(--orange); box-shadow: 0 0 0 1px rgba(255,176,95,.65), 0 0 18px rgba(255,176,95,.25); }
.resistance-range::-moz-range-thumb { background: var(--orange); box-shadow: 0 0 0 1px rgba(255,176,95,.65), 0 0 18px rgba(255,176,95,.25); }
.range-scale { display: flex; justify-content: space-between; margin-top: 10px; color: #667b98; font-family: ui-monospace, monospace; font-size: 8px; }

.section-label { display: flex; align-items: center; justify-content: space-between; color: var(--muted); letter-spacing: .1em; }
.section-label small { color: var(--cyan); font-size: 8px; }
.preset-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-top: 13px; }
.preset-grid button {
  position: relative;
  min-height: 74px;
  padding: 12px 11px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: rgba(25, 43, 70, 0.28);
  cursor: pointer;
  text-align: left;
  transition: 160ms ease;
}
.preset-grid button:hover { border-color: var(--line-strong); background: var(--panel-soft); }
.preset-grid button.selected { border-color: rgba(72, 215, 232, 0.5); background: rgba(72, 215, 232, 0.09); box-shadow: inset 0 0 24px rgba(72, 215, 232, 0.04); }
.preset-grid button > span { position: absolute; top: 9px; right: 9px; color: #5f7390; font-family: ui-monospace, monospace; font-size: 8px; }
.preset-grid strong, .preset-grid small { display: block; }
.preset-grid strong { margin-top: 3px; font-size: 10px; }
.preset-grid small { margin-top: 7px; color: var(--quiet); font-family: ui-monospace, monospace; font-size: 8px; }
.preset-grid button.selected strong { color: var(--cyan); }

.derived-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-top: 13px; }
.derived-grid > div { padding: 11px; border: 1px solid var(--line); border-radius: 9px; background: rgba(4, 12, 23, 0.42); }
.derived-grid small, .derived-grid strong { display: block; }
.derived-grid small { color: var(--quiet); font-size: 8px; text-transform: uppercase; }
.derived-grid strong { margin-top: 6px; color: var(--blue); font-family: ui-monospace, monospace; font-size: 11px; }
.thermal-status {
  display: flex;
  align-items: center;
  gap: 9px;
  margin-top: 10px;
  padding: 10px 11px;
  border: 1px solid rgba(98,223,179,.2);
  border-radius: 9px;
  background: rgba(98,223,179,.06);
  color: var(--green);
  font-size: 9px;
}
.thermal-status i { width: 6px; height: 6px; border-radius: 50%; background: var(--green); box-shadow: 0 0 9px var(--green); }
.thermal-status.elevated { border-color: rgba(255,176,95,.25); background: rgba(255,176,95,.07); color: var(--orange); }
.thermal-status.elevated i { background: var(--orange); box-shadow: 0 0 9px var(--orange); }
.thermal-status.high { border-color: rgba(255,122,133,.3); background: rgba(255,122,133,.08); color: var(--danger); }
.thermal-status.high i { background: var(--danger); box-shadow: 0 0 9px var(--danger); }

.equation-card { margin: 0 22px 16px; padding: 18px; border: 1px solid rgba(72,215,232,.24); border-radius: 13px; background: linear-gradient(145deg, rgba(72,215,232,.09), rgba(110,168,255,.04)); }
.equation-card > div { display: flex; justify-content: space-between; color: var(--cyan); font-family: ui-monospace, monospace; font-size: 8px; font-weight: 800; letter-spacing: .11em; }
.equation-card > div small { color: var(--quiet); font-size: 7px; }
.equation-card > strong { display: block; margin-top: 18px; color: var(--text); font-family: ui-monospace, monospace; font-size: 25px; font-weight: 600; letter-spacing: -.05em; }
.equation-card code { display: block; margin-top: 12px; padding: 10px; border-radius: 8px; background: rgba(4,12,23,.65); color: var(--cyan); font-family: ui-monospace, monospace; font-size: 10px; }
.equation-card p { min-height: 29px; margin: 10px 0 0; color: var(--quiet); font-size: 9px; line-height: 1.5; }
.control-note { display: grid; grid-template-columns: 23px 1fr; gap: 10px; margin: 0 22px 22px; padding-top: 2px; }
.control-note > span { display: grid; width: 21px; height: 21px; place-items: center; border: 1px solid var(--line); border-radius: 50%; color: var(--quiet); font-family: ui-monospace, monospace; font-size: 9px; }
.control-note p { margin: 1px 0 0; color: #7185a0; font-size: 8px; line-height: 1.55; }

.graph-panel { min-width: 0; }
.slope-badge { flex: 0 0 auto; padding: 9px 11px; color: var(--purple); white-space: nowrap; }
.graph-frame { margin: 0 14px; overflow: hidden; border: 1px solid var(--line); border-radius: 13px; background: rgba(4, 12, 23, 0.66); }
#viGraph { display: block; width: 100%; height: auto; }
.graph-footer { display: flex; flex-wrap: wrap; gap: 18px; padding: 14px 28px 20px; color: var(--quiet); font-family: ui-monospace, monospace; font-size: 8px; text-transform: uppercase; }
.graph-footer span { display: inline-flex; align-items: center; gap: 7px; }
.graph-footer span:last-child { margin-left: auto; color: var(--purple); }
.graph-line-key { width: 16px; height: 3px; background: var(--purple); }
.graph-point-key { width: 7px; height: 7px; border: 2px solid var(--cyan); border-radius: 50%; }

.observation-panel {
  display: grid;
  grid-template-columns: auto 1fr auto;
  gap: 22px;
  align-items: center;
  margin-top: 18px;
  padding: 23px 28px;
  border: 1px solid rgba(72, 215, 232, 0.22);
  border-radius: 16px;
  background:
    linear-gradient(90deg, rgba(72, 215, 232, 0.08), rgba(110, 168, 255, 0.04)),
    rgba(13, 28, 47, 0.92);
}
.observation-mark { display: grid; width: 46px; height: 46px; place-items: center; border: 1px solid rgba(72,215,232,.36); border-radius: 11px; background: rgba(72,215,232,.09); color: var(--cyan); font-family: Georgia, serif; font-size: 25px; }
.observation-panel h2 { margin-top: 4px; }
.observation-panel p { margin: 6px 0 0; color: var(--muted); font-size: 11px; }
.observation-formula { min-width: 190px; padding-left: 26px; border-left: 1px solid var(--line); }
.observation-formula span, .observation-formula strong { display: block; }
.observation-formula span { color: var(--quiet); font-family: ui-monospace, monospace; font-size: 8px; letter-spacing: .12em; }
.observation-formula strong { margin-top: 8px; color: var(--cyan); font-family: ui-monospace, monospace; font-size: 20px; }

.notebook-section { margin-top: 18px; }
.notebook-header { align-items: center; }
.notebook-actions { display: flex; flex: 0 0 auto; gap: 8px; }
.primary-button, .secondary-button {
  display: inline-flex;
  min-height: 39px;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 0 14px;
  border-radius: 9px;
  cursor: pointer;
  font-size: 9px;
  font-weight: 800;
  letter-spacing: .03em;
}
.primary-button { border: 1px solid var(--cyan); background: linear-gradient(135deg, var(--cyan), var(--blue)); color: #06101d; }
.primary-button:hover { filter: brightness(1.08); }
.primary-button span { font-size: 16px; line-height: 1; }
.secondary-button { border: 1px solid var(--line); background: var(--panel-soft); color: var(--muted); }
.secondary-button:hover:not(:disabled) { border-color: var(--line-strong); color: var(--text); }
.secondary-button:disabled { cursor: not-allowed; opacity: .38; }
.hidden { display: none !important; }
.table-wrap { margin: 0 14px 14px; overflow-x: auto; border: 1px solid var(--line); border-radius: 12px; }
table { width: 100%; min-width: 720px; border-collapse: collapse; font-size: 10px; }
th, td { padding: 14px 17px; border-bottom: 1px solid var(--line); text-align: left; }
th { background: rgba(4,12,23,.42); color: var(--quiet); font-family: ui-monospace, monospace; font-size: 8px; letter-spacing: .09em; text-transform: uppercase; }
td { color: var(--muted); font-family: ui-monospace, monospace; }
tbody tr:last-child td { border-bottom: 0; }
tbody tr:not(.empty-row):hover { background: rgba(72,215,232,.025); }
.trial-number { color: var(--cyan); font-weight: 800; }
.empty-row td { height: 86px; color: #667a96; text-align: center; }
.table-status { display: inline-flex; padding: 5px 8px; border: 1px solid var(--line); border-radius: 999px; color: var(--quiet); font-family: Inter, sans-serif; font-size: 8px; font-weight: 800; }
.table-status.closed { border-color: rgba(98,223,179,.22); background: rgba(98,223,179,.07); color: var(--green); }

.theory-grid { display: grid; grid-template-columns: 1.35fr .65fr; gap: 18px; margin-top: 18px; }
.theory-card, .investigation-card { padding: 28px; }
.theory-card > p { max-width: 580px; }
.formula-row { display: grid; grid-template-columns: repeat(3, 1fr); margin-top: 24px; overflow: hidden; border: 1px solid var(--line); border-radius: 12px; }
.formula-row > div { padding: 18px; border-right: 1px solid var(--line); background: rgba(4,12,23,.32); }
.formula-row > div:last-child { border-right: 0; }
.formula-row small, .formula-row strong { display: block; }
.formula-row small { color: var(--quiet); font-size: 8px; text-transform: uppercase; }
.formula-row strong { margin-top: 11px; color: var(--cyan); font-family: ui-monospace, monospace; font-size: clamp(15px, 1.7vw, 21px); }
.investigation-card { background: linear-gradient(145deg, rgba(25,43,70,.96), rgba(20,27,53,.96)); }
.investigation-card .panel-index { color: var(--purple); }
.investigation-card ol { margin: 21px 0 0; padding: 0; list-style: none; }
.investigation-card li { display: grid; grid-template-columns: 27px 1fr; gap: 11px; padding: 13px 0; border-top: 1px solid var(--line); }
.investigation-card li > span { color: var(--purple); font-family: ui-monospace, monospace; font-size: 8px; font-weight: 800; }
.investigation-card p { margin: 0; color: var(--quiet); font-size: 10px; line-height: 1.55; }
.investigation-card strong { color: var(--text); }

footer {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 20px;
  margin-top: 42px;
  padding: 34px 2px 10px;
  border-top: 1px solid var(--line);
}
.footer-brand .brand-mark { flex-basis: 34px; width: 34px; height: 34px; border-radius: 9px; font-size: 17px; }
.footer-brand strong, .footer-brand small { display: block; }
.footer-brand strong { font-size: 11px; }
.footer-brand small { margin-top: 4px; color: var(--quiet); font-size: 8px; }
footer p { color: var(--quiet); font-family: ui-monospace, monospace; font-size: 8px; text-align: center; text-transform: uppercase; }
footer > a { justify-self: end; color: var(--cyan); font-size: 9px; font-weight: 700; text-decoration: none; }
.noscript { position: fixed; z-index: 99; right: 18px; bottom: 18px; left: 18px; margin: 0; padding: 13px; border: 1px solid rgba(255,122,133,.4); border-radius: 10px; background: #40151c; color: #fff; font-size: 12px; text-align: center; }

@media (max-width: 1160px) {
  .workspace { grid-template-columns: 1fr; }
  .control-panel { position: static; display: grid; grid-template-columns: 1fr 1fr; }
  .control-panel > .panel-header, .control-panel > .preset-section, .control-panel > .derived-section, .control-panel > .equation-card, .control-panel > .control-note { grid-column: 1 / -1; }
  .control-panel > .control-group { margin-top: 0; border-top: 1px solid var(--line); }
  .control-panel > .control-group:nth-of-type(2) { border-left: 1px solid var(--line); }
  .preset-grid { grid-template-columns: repeat(4, 1fr); }
  .derived-grid { grid-template-columns: repeat(4, 1fr); }
}

@media (max-width: 900px) {
  .topbar-actions .live-pill { display: none; }
  .lab-intro { grid-template-columns: 1fr; gap: 18px; }
  .measurement-grid { grid-template-columns: 1fr 1fr; }
  .measurement:nth-child(2) { border-right: 0; }
  .measurement:nth-child(-n + 2) { border-bottom: 1px solid var(--line); }
  .theory-grid { grid-template-columns: 1fr; }
  .notebook-header { align-items: flex-start; flex-direction: column; }
  .notebook-actions { width: 100%; }
  .notebook-actions .primary-button { margin-left: auto; }
}

@media (max-width: 680px) {
  .app-shell { width: min(100% - 24px, 1480px); }
  .topbar { min-height: 76px; }
  .brand-mark { flex-basis: 36px; width: 36px; height: 36px; }
  .brand-kicker { font-size: 7px; }
  .brand-copy strong { font-size: 14px; }
  .brand-copy small, .topbar-actions .quiet-button:first-of-type { display: none; }
  .topbar-actions { gap: 0; }
  .quiet-button { min-height: 34px; padding: 0 10px; font-size: 8px; }
  .status-strip { overflow-x: auto; }
  .status-strip > span { flex: 0 0 auto; padding: 0 12px; }
  .section-tabs { gap: 19px; overflow-x: auto; }
  .section-tabs a { flex: 0 0 auto; }
  main { padding-top: 31px; }
  .lab-intro { padding-bottom: 24px; }
  .lab-intro h1 { font-size: clamp(31px, 10vw, 45px); }
  .lab-intro > p { font-size: 12px; }
  .panel { border-radius: 15px; }
  .panel-header { padding: 21px 18px 18px; }
  .panel-header h2, .observation-panel h2, .theory-card h2, .investigation-card h2 { font-size: 18px; }
  .panel-header p { font-size: 10px; }
  .status-chip { padding: 7px 9px; font-size: 7px; }
  .measurement-grid { margin: 0 12px 12px; }
  .measurement { padding: 12px; }
  .measurement strong { font-size: 15px; }
  .apparatus-stage { margin: 0 8px; overflow-x: auto; }
  .circuit-svg { min-width: 640px; }
  .stage-label, .stage-legend { min-width: 640px; }
  .transport-bar { margin: 0 10px; gap: 11px; }
  .run-button { min-width: 139px; padding: 8px; }
  .run-icon { width: 30px; height: 30px; }
  .model-badge { display: none; }
  .transport-reading strong { max-width: 210px; }
  .control-panel { display: block; }
  .control-panel > .control-group:nth-of-type(2) { border-left: 0; }
  .control-group, .preset-section, .derived-section { margin: 0 16px; }
  .preset-grid { grid-template-columns: 1fr 1fr; }
  .derived-grid { grid-template-columns: 1fr 1fr; }
  .equation-card { margin-inline: 16px; }
  .control-note { margin-inline: 16px; }
  .graph-frame { margin: 0 8px; overflow-x: auto; }
  #viGraph { min-width: 650px; }
  .graph-footer { padding-inline: 18px; }
  .graph-footer span:last-child { width: 100%; margin-left: 0; }
  .observation-panel { grid-template-columns: auto 1fr; padding: 20px 18px; }
  .observation-formula { grid-column: 1 / -1; padding: 17px 0 0; border-top: 1px solid var(--line); border-left: 0; }
  .notebook-actions { flex-wrap: wrap; }
  .notebook-actions .primary-button { margin-left: 0; }
  .table-wrap { margin: 0 8px 8px; }
  .theory-card, .investigation-card { padding: 22px 18px; }
  .formula-row { grid-template-columns: 1fr; }
  .formula-row > div { border-right: 0; border-bottom: 1px solid var(--line); }
  .formula-row > div:last-child { border-bottom: 0; }
  footer { grid-template-columns: 1fr auto; }
  footer p { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }
  .electron-flow { display: none; }
}