:root {
  color-scheme: dark;
  --bg: #12100e;
  --panel: #1c1814;
  --panel-2: #26211b;
  --line: #3d342b;
  --text: #f6efe4;
  --muted: #b5a894;
  --brass: #e2b657;
  --brass-ink: #2a2112;
  --coral: #ef6f4c;
  --teal: #79c2a8;
  --blue: #8eb4e8;
  --violet: #c4a1ff;
  --paper: #17140f;
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.35);
  font-family: "Avenir Next", "Segoe UI", "Trebuchet MS", sans-serif;
}

* { box-sizing: border-box; }

[hidden] { display: none !important; }

html, body {
  margin: 0;
  min-height: 100%;
  background:
    radial-gradient(1200px 500px at 10% -10%, rgba(226, 182, 87, 0.08), transparent 55%),
    var(--bg);
  color: var(--text);
}

body {
  min-height: 100vh;
}

button, input, select, textarea { font: inherit; color: inherit; }

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

.shell {
  display: grid;
  grid-template-columns: minmax(280px, 360px) minmax(0, 1fr);
  height: 100vh;
  min-height: 100vh;
  overflow: hidden;
}

.panel {
  padding: 1.4rem 1.25rem 1.6rem;
  border-right: 1px solid var(--line);
  background: rgba(28, 24, 20, 0.94);
  display: flex;
  flex-direction: column;
  gap: 1rem;
  max-height: 100vh;
  overflow: auto;
}

.eyebrow {
  margin: 0;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-size: 0.72rem;
  color: var(--brass);
}

h1 {
  margin: 0.2rem 0 0;
  font-family: Palatino, "Iowan Old Style", "Palatino Linotype", Georgia, serif;
  font-size: 2.4rem;
  font-weight: 600;
  letter-spacing: -0.03em;
}

.lede {
  margin: 0.35rem 0 0;
  color: var(--muted);
  line-height: 1.45;
}

.controls, .compare {
  display: grid;
  gap: 0.75rem;
}

.compare {
  margin: 0;
  padding: 0.85rem;
  border: 1px solid var(--line);
  border-radius: 16px;
}

.compare legend {
  padding: 0 0.35rem;
  color: var(--brass);
}

.compare-list {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.35rem 0.75rem;
}

.compare-list label {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  color: var(--text);
}

.compare-list label:has(input:disabled) {
  opacity: 0.45;
}

.compare-list input:disabled {
  cursor: not-allowed;
}

.hint {
  margin: 0;
  color: var(--muted);
  font-size: 0.8rem;
  line-height: 1.4;
}

.formula-row {
  display: flex;
  align-items: baseline;
  gap: 0.6rem;
  min-height: 2.4rem;
  margin: 0;
}

.formula .katex {
  font-size: 1.45rem;
  color: var(--brass);
}

.case-label {
  color: var(--muted);
  font-size: 0.85rem;
}

.bound-line {
  margin: 0;
}

.bound-line .katex {
  font-size: 1.2rem;
  color: var(--text);
}

.result-name {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.45rem 0.7rem;
}

.lane-card .bound-line {
  margin-left: auto;
}

.lane-card .result-name {
  font-size: calc(0.92rem * var(--lane-type, 1));
  gap: calc(0.2rem * var(--lane-scale)) calc(0.35rem * var(--lane-scale));
}

.result-name .katex {
  font-size: clamp(0.805rem, calc(0.92rem * var(--lane-type, 1)), 1.058rem);
}

.results {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: calc(0.4rem * var(--lane-scale));
  flex: 0 1 auto;
  min-height: 0;
}

.results li {
  display: grid;
  gap: calc(0.22rem * var(--lane-scale));
  border: 1px solid var(--line);
  border-radius: calc(12px * var(--lane-scale));
  padding: calc(0.38rem * var(--lane-scale)) calc(0.48rem * var(--lane-scale));
  background: rgba(28, 24, 20, 0.88);
}

.lane-card .readout {
  gap: calc(0.28rem * var(--lane-scale));
}

.lane-card .stat {
  padding: calc(0.22rem * var(--lane-scale)) calc(0.32rem * var(--lane-scale));
  border-radius: calc(8px * var(--lane-scale));
}

.lane-card .stat {
  min-width: 0;
}

.lane-card .stat span {
  font-size: clamp(0.667rem, calc(0.72rem * var(--lane-type, 1)), 0.828rem);
  letter-spacing: 0.02em;
  line-height: 1.15;
}

.lane-card .stat strong {
  margin-top: calc(0.06rem * var(--lane-scale));
  font-size: clamp(0.8625rem, calc(1.05rem * var(--lane-type, 1)), 1.2075rem);
  line-height: 1.1;
}

.lane-card .bound-line {
  line-height: 1.2;
}

.lane-card .bound-line .katex {
  font-size: clamp(0.805rem, calc(0.92rem * var(--lane-type, 1)), 1.058rem);
  line-height: 1.2;
}

.lane-meter {
  display: grid;
  grid-template-columns: minmax(0, 1.3fr) minmax(0, 1fr);
  gap: calc(0.35rem * var(--lane-scale));
  align-items: center;
}

.lane-card .meter {
  height: max(2.3px, calc(0.32rem * var(--lane-scale)));
}

.lane-card .note {
  margin: 0;
  min-height: 0;
  font-size: clamp(0.713rem, calc(0.78rem * var(--lane-type, 1)), 0.897rem);
  line-height: 1.2;
}

.viz-dock {
  display: none;
}

.results strong { font-weight: 650; }
.results span { color: var(--muted); font-variant-numeric: tabular-nums; }

label, .field {
  display: grid;
  gap: 0.35rem;
  color: var(--muted);
  font-size: 0.86rem;
}

select, textarea, input[type="number"] {
  width: 100%;
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.55rem 0.7rem;
}

.slider-row input[type="number"] {
  width: 5.2rem;
  padding: 0.35rem 0.45rem;
  text-align: right;
}

textarea {
  min-height: 4.6rem;
  resize: vertical;
}

.slider-row {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.6rem;
  align-items: center;
}

input[type="range"] {
  width: 100%;
  accent-color: var(--brass);
}

output {
  min-width: 4.5rem;
  text-align: right;
  color: var(--text);
  font-variant-numeric: tabular-nums;
}

.blurb {
  margin: 0;
  min-height: 2.6rem;
  color: var(--text);
  line-height: 1.4;
}

.row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem;
}

button {
  background: var(--panel-2);
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 0.55rem 0.85rem;
  cursor: pointer;
}

button:hover { border-color: var(--brass); }

button.primary {
  background: var(--brass);
  color: var(--brass-ink);
  border-color: transparent;
  font-weight: 700;
}

button[aria-pressed="true"] {
  border-color: var(--brass);
  color: var(--brass);
}

.error {
  min-height: 1.2rem;
  margin: 0;
  color: var(--coral);
}

.stage {
  display: flex;
  flex-direction: column;
  min-width: 0;
  min-height: 0;
  height: 100%;
  padding: 1.2rem;
  gap: calc(0.7rem * var(--lane-scale, 1));
  overflow: hidden;
}

.canvas-frame {
  position: relative;
  flex: 1 1 auto;
  min-height: 34vh;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: 22px;
  box-shadow: var(--shadow);
  overflow: hidden;
}

canvas {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem 1rem;
  margin: 0;
  padding: 0;
  list-style: none;
  color: var(--muted);
  font-size: 0.85rem;
}

.legend li { display: flex; align-items: center; gap: 0.4rem; }

.swatch {
  width: 0.75rem;
  height: 0.75rem;
  border-radius: 50%;
  display: inline-block;
}

.swatch.compare { background: var(--brass); }
.swatch.swap { background: var(--coral); }
.swatch.write { background: var(--blue); }
.swatch.pivot { background: var(--violet); }
.swatch.sorted { background: var(--teal); }

.readout {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 0.6rem;
}

.stat {
  background: rgba(28, 24, 20, 0.88);
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 0.7rem 0.8rem;
}

.stat span {
  display: block;
  color: var(--muted);
  font-size: 0.75rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.stat strong {
  display: block;
  margin-top: 0.2rem;
  font-size: 1.25rem;
  font-variant-numeric: tabular-nums;
  font-family: Palatino, Georgia, serif;
}

.meter {
  height: 0.45rem;
  background: #2c261f;
  border-radius: 999px;
  overflow: hidden;
}

.meter span {
  display: block;
  height: 100%;
  width: 0%;
  background: var(--brass);
}

.meter.over span { background: var(--coral); }

.note {
  margin: 0.35rem 0 0;
  color: var(--muted);
  min-height: 1.3rem;
}

@media (max-width: 900px) {
  .shell { grid-template-columns: 1fr; height: auto; overflow: visible; }
  .stage { height: auto; overflow: visible; }
  .panel { border-right: 0; border-bottom: 1px solid var(--line); max-height: none; }
  .canvas-frame { min-height: 240px; height: 46vh; flex: none; scroll-margin-top: 0.6rem; }
  .readout,
  .lane-card .readout { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .stat { min-width: 0; }
  .stat span { letter-spacing: 0.02em; }
  .stage:has(#viz-dock:not([hidden])) { padding-right: 5rem; }
  .viz-dock:not([hidden]) {
    display: flex;
    position: fixed;
    z-index: 4;
    right: 0.55rem;
    top: 42%;
    transform: translateY(-50%);
    flex-direction: column;
    align-items: center;
    gap: 0.55rem;
    width: 4.4rem;
    padding: 0.7rem 0.4rem;
    border: 1px solid var(--line);
    border-radius: 18px;
    background: rgba(28, 24, 20, 0.94);
  }
  .viz-dock label {
    justify-items: center;
    font-size: 0.68rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
  }
  .viz-dock input[type="range"] {
    writing-mode: vertical-lr;
    direction: rtl;
    width: 1.4rem;
    height: 7.5rem;
    margin: 0.2rem 0;
  }
  .viz-dock button {
    padding: 0.4rem 0.35rem;
    font-size: 0.75rem;
  }
}