:root {
  --surface-panel: var(--bg);
  --surface-panel-strong: color-mix(in srgb, var(--text) 3%, transparent);
  --surface-delete: color-mix(in srgb, var(--muted) 88%, var(--text) 12%);
  --surface-insert: var(--accent);
  --surface-focus: color-mix(in srgb, var(--accent) 7%, transparent);
  --surface-mono: "SFMono-Regular", Menlo, Consolas, monospace;
  --surface-serif: Georgia, "Times New Roman", serif;
}

.quadrature-surface-page .site-main {
  width: min(1680px, calc(100vw - (var(--content-gutter) * 2)));
  max-width: none;
  margin-inline: auto;
}

.quadrature-surface-page .site-main > .page-hero {
  padding-inline: 0;
}

.quadrature-surface-page {
  background: var(--bg);
}

.quadrature-hero {
  display: grid;
  gap: 0.9rem;
}

.quadrature-hero .page-title {
  max-width: none;
}

.quadrature-surface {
  display: grid;
  gap: 1.35rem;
}

.quadrature-summary {
  display: grid;
  grid-template-columns: minmax(0, 0.82fr) minmax(500px, 1fr);
  gap: clamp(1.8rem, 3vw, 3.4rem);
  padding-bottom: 1.35rem;
  border-bottom: 1px solid var(--line);
  align-items: start;
}

.quadrature-summary .eyebrow {
  margin-bottom: 0;
}

.quadrature-summary-copy {
  display: grid;
  gap: 0.75rem;
  align-content: start;
}

.quadrature-summary-text {
  max-width: 62ch;
  margin: 0;
  color: var(--muted);
  font-size: 1rem;
  line-height: 1.6;
}

.quadrature-summary-text code {
  color: var(--text);
  font-family: var(--surface-mono);
  font-size: 0.92em;
}

.quadrature-summary-link {
  width: fit-content;
  color: var(--text);
  font-size: 0.92rem;
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--accent) 62%, transparent);
  text-underline-offset: 0.24em;
}

.quadrature-summary-panel {
  display: grid;
  gap: 0.85rem;
}

.quadrature-metrics {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0;
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.quadrature-metric {
  min-height: 82px;
  padding: 0.9rem 0.95rem 0.75rem;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.quadrature-metric-label {
  display: block;
  margin-bottom: 0.42rem;
  color: var(--muted);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.12em;
}

.quadrature-metric-value {
  display: block;
  font-size: 1.08rem;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.2;
}

.quadrature-metric-value--numeric {
  letter-spacing: -0.03em;
}

.quadrature-stage {
  display: grid;
  grid-template-columns: minmax(420px, 0.95fr) minmax(540px, 1.25fr);
  gap: clamp(2rem, 3vw, 4.2rem);
  align-items: start;
}

.quadrature-section-head,
.quadrature-score-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
}

.quadrature-section-title {
  margin: 0;
  font-size: 1.08rem;
  font-weight: 500;
  letter-spacing: -0.02em;
}

.quadrature-section-tag {
  display: inline-flex;
  align-items: center;
  padding: 0.35rem 0.58rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--muted);
  font-size: 0.78rem;
  line-height: 1;
}

.quadrature-section-tag.is-phase {
  color: var(--accent);
  border-color: color-mix(in srgb, var(--accent) 42%, transparent);
  background: color-mix(in srgb, var(--accent) 8%, transparent);
}

.quadrature-editor {
  position: relative;
  margin-top: 0.85rem;
  border: 1px solid var(--line);
  border-radius: 0;
  background: var(--surface-panel);
  overflow: hidden;
}

.quadrature-editor-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.95rem 1rem;
  border-bottom: 1px solid var(--line);
  background: var(--surface-panel);
}

.quadrature-editor-title {
  color: var(--muted);
  font-family: var(--surface-mono);
  font-size: 0.86rem;
}

.quadrature-editor-body {
  position: relative;
  height: 420px;
  overflow: hidden;
  background: var(--bg);
  --editor-font-size: 12.16px;
  --editor-line-height: 24px;
  --editor-ln-col: 34px;
  --editor-pm-col: 14px;
  --editor-gap-col: 0.45rem;
  --editor-pad-x: 0.55rem;
}

.quadrature-editor-focus {
  display: none;
}

.quadrature-editor-line {
  position: absolute;
  left: 12px;
  right: 12px;
  display: grid;
  grid-template-columns: var(--editor-ln-col) var(--editor-pm-col) minmax(0, 1fr);
  gap: var(--editor-gap-col);
  align-items: center;
  height: var(--editor-line-height);
  padding: 0 var(--editor-pad-x);
  border-radius: 0;
  font-family: var(--surface-mono);
  font-size: var(--editor-font-size);
  line-height: 1;
  white-space: pre;
  pointer-events: none;
  transform-origin: left center;
  will-change: transform, opacity, height;
  transition: background-color 220ms ease, color 220ms ease;
}

.quadrature-editor-line.equal {
  color: color-mix(in srgb, var(--text) 88%, transparent);
  background: transparent;
}

.quadrature-editor-line.delete {
  color: var(--surface-delete);
  background: color-mix(in srgb, var(--text) 4%, transparent);
}

.quadrature-editor-line.insert {
  color: var(--surface-insert);
  background: color-mix(in srgb, var(--accent) 7%, transparent);
}

.quadrature-editor-line .ln {
  color: var(--muted);
  text-align: right;
}

.quadrature-editor-line .pm {
  font-weight: 600;
  opacity: 0.95;
}

.quadrature-editor-line .code {
  display: block;
  width: max-content;
  transform: scaleX(var(--editor-code-scale, 1));
  transform-origin: left center;
}

.quadrature-editor-line.delete .code {
  text-decoration: line-through;
  text-decoration-thickness: 1.5px;
}

.quadrature-visual {
  display: grid;
  gap: 1rem;
}

.quadrature-score-pulse,
.quadrature-rule,
.quadrature-mini-chart {
  background: var(--surface-panel);
  border: 1px solid var(--line);
  border-radius: 0;
}

.quadrature-score-pulse,
.quadrature-rule {
  padding: 0.9rem 0.95rem 0.7rem;
}

.quadrature-score-label {
  color: var(--muted);
  font-size: 0.76rem;
}

.quadrature-score-svg,
.quadrature-rule-svg,
.quadrature-mini-svg {
  overflow: visible;
}

.quadrature-score-svg text,
.quadrature-rule-svg text,
.quadrature-mini-svg text {
  font-family: var(--surface-serif);
}

.quadrature-figure-title {
  fill: var(--text);
  font-family: var(--surface-serif);
  font-size: 12px;
  font-style: italic;
}

.quadrature-axis-title,
.quadrature-axis-tick,
.quadrature-rule-note {
  fill: var(--muted);
  font-family: var(--surface-serif);
}

.quadrature-axis-title {
  font-size: 10.5px;
  text-anchor: middle;
}

.quadrature-axis-tick {
  font-size: 9.5px;
  font-variant-numeric: tabular-nums;
  text-anchor: middle;
}

.quadrature-rule-note {
  font-size: 8.5px;
  font-style: italic;
}

.quadrature-paper-axis {
  stroke: color-mix(in srgb, var(--text) 58%, transparent);
  stroke-width: 1;
  fill: none;
}

.quadrature-paper-grid {
  stroke: color-mix(in srgb, var(--text) 16%, transparent);
  stroke-width: 0.8;
  fill: none;
}

.quadrature-score-legend text,
.quadrature-rule-legend text {
  fill: var(--muted);
  font-family: var(--surface-serif);
  font-size: 8.5px;
}

.quadrature-score-proposal {
  fill: color-mix(in srgb, var(--text) 28%, transparent);
}

.quadrature-score-best {
  fill: none;
  stroke: var(--text);
  stroke-width: 2.3;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.quadrature-score-baseline {
  fill: var(--bg);
  stroke: color-mix(in srgb, var(--text) 55%, transparent);
  stroke-width: 2;
}

.quadrature-score-accepted,
.quadrature-score-current,
.quadrature-rule-node {
  fill: var(--bg);
  stroke: var(--accent);
  stroke-width: 2;
}

.quadrature-score-current {
  fill: var(--accent);
}

.quadrature-score-title {
  font-size: 13.5px;
}

.quadrature-score-subtitle,
.quadrature-score-current-label,
.quadrature-score-annotation {
  fill: var(--muted);
  font-family: var(--surface-serif);
}

.quadrature-score-subtitle {
  font-size: 9.5px;
  font-style: italic;
}

.quadrature-score-current-label {
  font-size: 10px;
  font-style: italic;
  text-anchor: end;
}

.quadrature-score-annotation {
  font-size: 10px;
  font-style: italic;
}

.quadrature-score-accepted-label {
  fill: var(--text);
}

.quadrature-score-y-tick {
  text-anchor: end;
}

.quadrature-score-x-value {
  text-anchor: middle;
}

.quadrature-score-x-label,
.quadrature-score-y-label,
.quadrature-rule-x-label,
.quadrature-rule-y-label {
  fill: color-mix(in srgb, var(--text) 78%, transparent);
  font-size: 12px;
}

.quadrature-score-y-label {
  font-size: 13px;
}

.quadrature-rule-x-value {
  text-anchor: middle;
}

.quadrature-score-x-tick {
  fill: none;
  stroke: color-mix(in srgb, var(--text) 42%, transparent);
  stroke-width: 0.8;
}

.quadrature-rule-stem {
  stroke: var(--accent);
  stroke-width: 1.35;
}

.quadrature-mini-curve {
  fill: none;
  stroke: var(--text);
  stroke-width: 1.7;
  stroke-linecap: round;
}

.quadrature-mini-node {
  fill: var(--bg);
  stroke: var(--accent);
  stroke-width: 1.6;
}

.quadrature-score-svg {
  display: block;
  width: 100%;
  height: 270px;
  margin-top: 0.5rem;
}

.quadrature-rule-svg {
  display: block;
  width: 100%;
  height: 240px;
  margin-top: 0.35rem;
}

.quadrature-integrands {
  display: grid;
  gap: 0.75rem;
}

.quadrature-mini-chart {
  padding: 0.8rem 0.8rem 0.4rem;
}

.quadrature-mini-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  margin-bottom: 0.45rem;
}

.quadrature-mini-head strong,
.quadrature-mini-head span {
  font-family: var(--surface-serif);
  font-style: italic;
}

.quadrature-mini-formula {
  color: var(--text);
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0;
}

.quadrature-mini-error {
  color: var(--muted);
  font-size: 0.86rem;
}

.quadrature-mini-formula var,
.quadrature-mini-error var {
  font-family: var(--surface-serif);
  font-style: italic;
}

.quadrature-mini-formula sub,
.quadrature-mini-error sub {
  position: relative;
  bottom: -0.18em;
  font-size: 0.68em;
  line-height: 0;
}

.quadrature-mini-svg {
  display: block;
  width: 100%;
  height: 140px;
}

.quadrature-mini-svg pattern line {
  stroke: color-mix(in srgb, var(--text) 44%, transparent);
  stroke-width: 1;
}

.quadrature-mini-cell-area {
  fill: color-mix(in srgb, var(--accent) 2%, transparent);
  stroke: color-mix(in srgb, var(--text) 22%, transparent);
  stroke-width: 0.8;
}

.quadrature-mini-gap-fill {
  fill: color-mix(in srgb, var(--accent) 20%, transparent);
  stroke: color-mix(in srgb, var(--accent) 60%, transparent);
  stroke-width: 0.7;
}

.quadrature-mini-gap-hatch {
  fill: var(--mini-hatch);
  stroke: none;
  opacity: 0.78;
}

.quadrature-mini-stem {
  stroke: color-mix(in srgb, var(--accent) 48%, transparent);
  stroke-width: 0.7;
}

@media (max-width: 1100px) {
  .quadrature-summary {
    grid-template-columns: 1fr;
  }

  .quadrature-stage {
    grid-template-columns: 1fr;
  }

  .quadrature-visual {
    order: -1;
    padding-left: 0;
    border-left: 0;
    border-top: 1px solid var(--line);
    padding-top: 1rem;
  }
}

@media (max-width: 760px) {
  .quadrature-metrics {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .quadrature-editor-body {
    height: 980px;
  }

  .quadrature-editor-line {
    font-size: 0.7rem;
    grid-template-columns: 28px 12px minmax(0, 1fr);
  }
}

@media (prefers-reduced-motion: reduce) {
  .quadrature-editor,
  .quadrature-editor-body,
  .quadrature-editor-focus,
  .quadrature-editor-line {
    transition: none;
  }
}