:root {
  --site-ink: #102a43;
  --site-ink-soft: #334e68;
  --site-muted: #627d98;
  --site-paper: #ffffff;
  --site-wash: #f3f7f9;
  --site-line: #d9e2ec;
  --site-blue: #245b8a;
  --site-teal: #0d9488;
  --site-orange: #d97706;
  --site-red: #b3261e;
  --site-green: #176b45;
  --site-mono: "Cascadia Mono", "SFMono-Regular", Consolas, monospace;
  --site-sans: "Noto Sans SC", "Source Han Sans SC", "Microsoft YaHei", sans-serif;
}

html,
body {
  background: var(--site-wash);
  color: var(--site-ink);
}

body {
  font-family: var(--site-sans);
}

.page-layout-full .quarto-title-block {
  display: none;
}

.quarto-container {
  max-width: none;
}

#quarto-content {
  padding-top: 0;
}

.page-layout-full .content,
.page-layout-full main.content {
  max-width: none;
  padding: 0;
}

.site-home-hero,
.control-landing-hero,
.home-metrics,
.control-stat-strip,
.home-path,
.home-series-grid,
.learning-promise,
.pid-principles,
.pid-playground,
.control-roadmap,
.series-cta,
.series-notes,
.reference-grid,
.tools-hero,
.tool-catalog-grid,
.tool-evidence-strip,
.lab-workbench-hero,
.lab-step-strip,
.lab-resource-grid,
.tool-boundary-note {
  width: min(1180px, calc(100% - 48px));
  margin-right: auto;
  margin-left: auto;
}

.site-home-hero,
.control-landing-hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(420px, 0.86fr);
  gap: clamp(36px, 7vw, 96px);
  align-items: center;
  min-height: min(720px, calc(100vh - 56px));
  padding: clamp(64px, 9vw, 120px) 0 clamp(54px, 8vw, 96px);
}

.hero-copy,
.control-hero-copy {
  max-width: 650px;
}

.eyebrow {
  margin: 0 0 14px;
  color: var(--site-teal);
  font-family: var(--site-mono);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  line-height: 1.4;
}

.site-home-hero h1,
.control-landing-hero h1 {
  max-width: 9ch;
  margin: 0;
  color: var(--site-ink);
  font-family: var(--site-sans);
  font-size: clamp(3.25rem, 7vw, 6.5rem);
  font-weight: 800;
  letter-spacing: -0.045em;
  line-height: 0.98;
  text-wrap: balance;
}

.control-landing-hero h1 {
  font-size: clamp(3rem, 6vw, 5.4rem);
}

.hero-copy > p:not(.eyebrow),
.control-hero-copy > h2,
.control-hero-copy > p:not(.eyebrow):not(.hero-footnote) {
  max-width: 600px;
  margin: 28px 0 0;
  color: var(--site-ink-soft);
  font-size: clamp(1.05rem, 1.5vw, 1.3rem);
  line-height: 1.8;
}

.control-hero-copy h2 {
  margin: 24px 0 0;
  font-size: clamp(1.45rem, 2.2vw, 2.2rem);
  line-height: 1.25;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
  margin-top: 34px;
}

.btn-primary,
.btn-secondary,
.reset-button {
  display: inline-flex;
  min-height: 46px;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  border-radius: 4px;
  padding: 11px 18px;
  font-family: var(--site-sans);
  font-size: 0.95rem;
  font-weight: 700;
  line-height: 1.2;
  text-decoration: none;
  transition: background-color 180ms ease, border-color 180ms ease, color 180ms ease, transform 180ms ease;
}

.btn-primary {
  background: var(--site-orange);
  color: #ffffff !important;
}

.btn-secondary {
  border-color: var(--site-ink);
  background: transparent;
  color: var(--site-ink) !important;
}

.btn-primary:hover,
.btn-secondary:hover,
.reset-button:hover {
  transform: translateY(-2px);
}

.btn-primary:hover {
  background: #b85f00;
}

.btn-secondary:hover {
  background: var(--site-ink);
  color: #ffffff !important;
}

.btn-primary:focus-visible,
.btn-secondary:focus-visible,
.reset-button:focus-visible,
input:focus-visible {
  outline: 3px solid rgba(13, 148, 136, 0.45);
  outline-offset: 3px;
}

.hero-note,
.hero-footnote {
  margin: 28px 0 0;
  color: var(--site-muted);
  font-size: 0.88rem;
}

.hero-signal,
.control-hero-visual {
  position: relative;
  min-height: 390px;
  overflow: hidden;
  border: 1px solid var(--site-line);
  background: var(--site-paper);
  box-shadow: 16px 16px 0 rgba(36, 91, 138, 0.09);
}

.hero-signal {
  width: 100%;
  aspect-ratio: 629 / 574;
  min-height: 0;
  margin: 0;
  padding: 0;
}

.hero-signal img {
  display: block;
  width: 100%;
  max-width: 100%;
  height: 100%;
  object-fit: contain;
}

.home-metrics,
.control-stat-strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  border-top: 1px solid var(--site-line);
  border-bottom: 1px solid var(--site-line);
}

.control-stat-strip {
  grid-template-columns: repeat(4, 1fr);
}

.metric,
.control-stat {
  display: flex;
  gap: 10px;
  align-items: baseline;
  padding: 24px 26px;
  border-right: 1px solid var(--site-line);
}

.metric:last-child,
.control-stat:last-child {
  border-right: 0;
}

.metric strong,
.control-stat strong {
  color: var(--site-orange);
  font-family: var(--site-mono);
  font-size: 1.5rem;
}

.metric span,
.control-stat span {
  color: var(--site-muted);
  font-size: 0.88rem;
}

.site-home-hero + .home-metrics,
.control-landing-hero + .control-stat-strip {
  margin-top: 0;
}

.page-layout-full main > h2,
.page-layout-full main > p:not(.eyebrow),
.page-layout-full main > .home-path,
.page-layout-full main > .home-series-grid,
.page-layout-full main > .series-cta,
.page-layout-full main > .series-notes,
.page-layout-full main > .tools-hero,
.page-layout-full main > .tool-catalog-grid,
.page-layout-full main > .tool-evidence-strip,
.page-layout-full main > .lab-workbench-hero,
.page-layout-full main > .lab-step-strip,
.page-layout-full main > .lab-resource-grid,
.page-layout-full main > .tool-boundary-note {
  width: min(1180px, calc(100% - 48px));
  margin-right: auto;
  margin-left: auto;
}

.page-layout-full main > h2 {
  margin-top: 86px;
  margin-bottom: 22px;
  border: 0;
  font-size: clamp(1.8rem, 3vw, 2.6rem);
}

.page-layout-full main > p:not(.eyebrow) {
  max-width: 720px;
  margin-bottom: 32px;
  color: var(--site-ink-soft);
  line-height: 1.8;
}

.home-path,
.home-series-grid,
.reference-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0;
  border-top: 1px solid var(--site-line);
  border-bottom: 1px solid var(--site-line);
}

.path-step {
  min-height: 210px;
  padding: 24px;
  border-right: 1px solid var(--site-line);
}

.path-step:last-child {
  border-right: 0;
}

.path-index {
  display: block;
  margin-bottom: 58px;
  color: var(--site-orange);
  font-family: var(--site-mono);
  font-size: 0.8rem;
  font-weight: 700;
}

.path-step strong,
.series-feature h3,
.reference-item h3 {
  display: block;
  margin: 0;
  font-size: 1.05rem;
}

.path-step p,
.series-feature p:not(.eyebrow),
.reference-item p:not(.eyebrow) {
  margin: 10px 0 0;
  color: var(--site-muted);
  font-size: 0.9rem;
  line-height: 1.7;
}

.home-series-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.series-feature,
.reference-item {
  min-height: 240px;
  padding: 28px;
  border-right: 1px solid var(--site-line);
}

.series-feature:last-child,
.reference-item:last-child {
  border-right: 0;
}

.series-feature-muted {
  background: rgba(255, 255, 255, 0.55);
}

.series-feature h3,
.reference-item h3 {
  margin-bottom: 8px;
  font-size: 1.35rem;
  line-height: 1.35;
}

.text-link,
.coming-soon {
  display: inline-block;
  margin-top: 26px;
  color: var(--site-blue);
  font-size: 0.9rem;
  font-weight: 700;
  text-decoration: none;
}

.coming-soon {
  color: var(--site-muted);
  font-family: var(--site-mono);
  font-size: 0.7rem;
}

.home-footer-callout,
.series-cta {
  display: flex;
  gap: 32px;
  align-items: center;
  justify-content: space-between;
  margin-top: 86px;
  margin-bottom: 80px;
  padding: 42px 0;
  border-top: 2px solid var(--site-ink);
  border-bottom: 1px solid var(--site-line);
}

.home-footer-callout h2,
.series-cta h2 {
  max-width: 680px;
  margin: 0;
  font-size: clamp(1.65rem, 3vw, 2.8rem);
  line-height: 1.2;
}

.control-landing-hero {
  grid-template-columns: minmax(0, 0.88fr) minmax(480px, 1.12fr);
  padding-top: clamp(58px, 8vw, 100px);
}

.control-hero-visual {
  min-height: 480px;
  padding: 24px;
  background: #fbfdfe;
}

.control-visual-topline,
.result-toolbar {
  display: flex;
  justify-content: space-between;
  color: var(--site-muted);
  font-family: var(--site-mono);
  font-size: 0.66rem;
  font-weight: 700;
  letter-spacing: 0.06em;
}

.control-loop-diagram {
  display: grid;
  grid-template-columns: auto 26px auto 26px auto 26px auto;
  gap: 4px;
  align-items: center;
  margin-top: 68px;
}

.control-hero-visual::before {
  position: absolute;
  top: 145px;
  right: 5%;
  left: 5%;
  z-index: 0;
  border-top: 1px dashed rgba(13, 148, 136, 0.28);
  content: "";
}

.control-hero-visual::after {
  position: absolute;
  top: 141px;
  left: 3%;
  z-index: 2;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--site-orange);
  box-shadow: 0 0 0 4px rgba(217, 119, 6, 0.13);
  content: "";
  animation: signal-forward 3.2s ease-in-out infinite;
}

.loop-block {
  position: relative;
  z-index: 1;
  display: grid;
  min-width: 78px;
  min-height: 74px;
  place-content: center;
  border: 1px solid var(--site-line);
  background: #ffffff;
  text-align: center;
}

.loop-block span {
  font-family: var(--site-mono);
  font-size: 1.1rem;
  font-weight: 700;
}

.loop-block small {
  margin-top: 6px;
  color: var(--site-muted);
  font-size: 0.68rem;
}

.loop-controller {
  border-color: rgba(13, 148, 136, 0.45);
  background: rgba(13, 148, 136, 0.08);
}

.loop-controller span {
  color: var(--site-teal);
}

.loop-plant {
  border-color: rgba(36, 91, 138, 0.42);
  background: rgba(36, 91, 138, 0.07);
}

.loop-output {
  border-color: rgba(217, 119, 6, 0.45);
  background: rgba(217, 119, 6, 0.08);
}

.loop-arrow {
  position: relative;
  z-index: 1;
  color: var(--site-orange);
  font-size: 1.2rem;
  text-align: center;
}

.loop-feedback {
  position: absolute;
  right: 24px;
  bottom: 174px;
  left: 24px;
  height: 92px;
  border-bottom: 1px solid var(--site-teal);
  border-left: 1px solid var(--site-teal);
  border-right: 1px solid var(--site-teal);
}

.loop-feedback::before {
  position: absolute;
  bottom: -4px;
  left: 8%;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--site-teal);
  box-shadow: 0 0 0 4px rgba(13, 148, 136, 0.12);
  content: "";
  animation: signal-feedback 3.8s ease-in-out infinite;
}

.loop-feedback span {
  position: absolute;
  bottom: 12px;
  left: 50%;
  padding: 0 10px;
  background: #fbfdfe;
  color: var(--site-teal);
  font-family: var(--site-mono);
  font-size: 0.73rem;
  transform: translateX(-50%);
  white-space: nowrap;
}

.loop-feedback b {
  position: absolute;
  top: -12px;
  left: 14%;
  padding: 0 8px;
  background: #fbfdfe;
  color: var(--site-teal);
  font-size: 0.7rem;
  font-weight: 700;
}

.hero-plot {
  position: absolute;
  right: 28px;
  bottom: 24px;
  left: 28px;
  height: 138px;
  overflow: hidden;
  border-top: 1px solid var(--site-line);
  border-left: 1px solid var(--site-line);
}

.hero-plot svg {
  display: block;
  width: 100%;
  height: 100%;
}

.plot-grid-line,
.plot-target-path {
  fill: none;
  vector-effect: non-scaling-stroke;
}

.plot-grid-line {
  stroke: rgba(36, 91, 138, 0.12);
  stroke-width: 1;
}

.plot-grid-target {
  stroke: rgba(217, 119, 6, 0.24);
  stroke-dasharray: 5 6;
}

.plot-grid-settle {
  stroke: rgba(13, 148, 136, 0.22);
  stroke-dasharray: 2 5;
}

.plot-grid-axis {
  stroke: rgba(36, 91, 138, 0.2);
}

.plot-target-path {
  stroke: var(--site-orange);
  stroke-dasharray: 7 7;
  stroke-width: 2;
}

.plot-response-path {
  fill: none;
  stroke: var(--site-blue);
  stroke-linecap: round;
  stroke-linejoin: round;
  stroke-width: 3;
  vector-effect: non-scaling-stroke;
  stroke-dasharray: 900;
  stroke-dashoffset: 900;
  animation: response-draw 3.4s ease-out forwards;
}

.plot-peak-dot {
  fill: var(--site-blue);
  stroke: #ffffff;
  stroke-width: 2;
  vector-effect: non-scaling-stroke;
  animation: peak-pulse 2.8s ease-in-out 3.4s infinite;
}

@keyframes signal-forward {
  0%, 12% {
    transform: translateX(0);
    opacity: 0;
  }
  20% {
    opacity: 1;
  }
  78% {
    opacity: 1;
  }
  88%, 100% {
    transform: translateX(930%);
    opacity: 0;
  }
}

@keyframes signal-feedback {
  0%, 12% {
    transform: translateX(0);
    opacity: 0;
  }
  22% {
    opacity: 1;
  }
  76% {
    opacity: 1;
  }
  90%, 100% {
    transform: translateX(930%);
    opacity: 0;
  }
}

@keyframes response-draw {
  to {
    stroke-dashoffset: 0;
  }
}

@keyframes peak-pulse {
  0%, 100% {
    transform: scale(1);
    transform-origin: 151px 21px;
  }
  50% {
    transform: scale(1.35);
    transform-origin: 151px 21px;
  }
}

.plot-axis {
  position: absolute;
  color: var(--site-muted);
  font-family: var(--site-mono);
  font-size: 0.66rem;
}

.plot-axis-y {
  top: 8px;
  left: 8px;
}

.plot-axis-x {
  right: 8px;
  bottom: 8px;
}

.plot-label {
  position: absolute;
  padding: 2px 6px;
  background: #ffffff;
  font-size: 0.64rem;
  font-weight: 700;
}

.plot-label-overshoot {
  top: 6px;
  left: 27%;
  color: var(--site-red);
}

.plot-label-settle {
  top: 57px;
  right: 12%;
  color: var(--site-blue);
}

.status-dot {
  display: inline-block;
  width: 8px;
  height: 8px;
  margin-right: 7px;
  border-radius: 50%;
  background: var(--site-green);
  box-shadow: 0 0 0 4px rgba(23, 107, 69, 0.1);
}

.learning-promise {
  display: grid;
  grid-template-columns: minmax(220px, 0.7fr) minmax(0, 1.3fr);
  gap: 48px;
  padding: 44px 0;
  border-top: 1px solid var(--site-line);
  border-bottom: 1px solid var(--site-line);
}

.promise-lead h2 {
  margin: 0;
  font-size: clamp(1.55rem, 2.7vw, 2.5rem);
  line-height: 1.25;
}

.promise-list {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 28px;
}

.promise-list > div {
  display: grid;
  grid-template-columns: 32px 1fr;
  column-gap: 12px;
  align-content: start;
}

.promise-list span,
.roadmap-item > span {
  color: var(--site-orange);
  font-family: var(--site-mono);
  font-size: 0.78rem;
  font-weight: 700;
}

.promise-list strong {
  font-size: 1rem;
}

.promise-list p {
  grid-column: 2;
  margin: 6px 0 0;
  color: var(--site-muted);
  font-size: 0.88rem;
  line-height: 1.7;
}

.pid-principles {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0;
  border-top: 1px solid var(--site-line);
  border-bottom: 1px solid var(--site-line);
}

.pid-principle {
  display: grid;
  grid-template-columns: 58px 1fr;
  gap: 18px;
  min-height: 240px;
  padding: 30px;
  border-right: 1px solid var(--site-line);
}

.pid-principle:last-child {
  border-right: 0;
}

.principle-mark {
  display: grid;
  width: 48px;
  height: 48px;
  place-items: center;
  border: 1px solid currentColor;
  border-radius: 50%;
  font-family: var(--site-mono);
  font-size: 1.25rem;
  font-weight: 700;
}

.pid-principle-p .principle-mark,
.pid-principle-p h3 {
  color: var(--site-blue);
}

.pid-principle-i .principle-mark,
.pid-principle-i h3 {
  color: var(--site-teal);
}

.pid-principle-d .principle-mark,
.pid-principle-d h3 {
  color: var(--site-orange);
}

.pid-principle h3 {
  margin: 0;
  font-size: 1.35rem;
}

.pid-principle p:not(.eyebrow) {
  margin: 12px 0 0;
  color: var(--site-muted);
  font-size: 0.9rem;
  line-height: 1.75;
}

.pid-playground {
  border: 1px solid var(--site-line);
  background: var(--site-paper);
}

.playground-heading {
  display: grid;
  grid-template-columns: minmax(220px, 0.7fr) minmax(0, 1.3fr);
  gap: 36px;
  padding: 30px;
  border-bottom: 1px solid var(--site-line);
}

.playground-heading h2 {
  margin: 0;
  border: 0;
  font-size: clamp(1.55rem, 2.5vw, 2.3rem);
}

.playground-heading > p {
  margin: 0;
  color: var(--site-muted);
  font-size: 0.92rem;
  line-height: 1.75;
}

.playground-layout {
  display: grid;
  grid-template-columns: minmax(280px, 320px) minmax(0, 1fr);
  align-items: start;
  min-height: 720px;
}

.playground-controls {
  position: sticky;
  top: 20px;
  max-height: calc(100vh - 40px);
  overflow-y: auto;
  display: grid;
  grid-template-columns: 1fr;
  gap: 18px;
  align-content: start;
  padding: 30px;
  border-right: 1px solid var(--site-line);
}

.playground-controls > .pid-live-controls {
  grid-template-columns: 1fr;
  gap: 16px 24px;
  margin-bottom: 2px;
  padding-bottom: 18px;
  border-bottom: 1px solid var(--site-line);
}

.playground-controls > .pid-presets,
.playground-controls > #pid-reset {
  grid-column: 1 / -1;
}

.control-field label {
  display: flex;
  justify-content: space-between;
  color: var(--site-ink);
  font-size: 0.9rem;
  font-weight: 700;
}

.control-field output {
  color: var(--site-teal);
  font-family: var(--site-mono);
}

.control-field input {
  width: 100%;
  margin-top: 14px;
  accent-color: var(--site-teal);
}

.control-field small {
  display: block;
  margin-top: 6px;
  color: var(--site-muted);
  font-size: 0.76rem;
  line-height: 1.55;
}

.pid-live-controls {
  display: grid;
  gap: 18px;
  margin-bottom: 18px;
}

.pid-runtime-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 4px;
}

.pid-live-controls .control-section-label {
  margin-top: 8px;
}

.pid-live-controls select {
  display: block;
  width: 100%;
  max-width: 100%;
  min-height: 34px;
  margin-top: 8px;
  padding: 4px 28px 4px 8px;
  color: var(--site-ink);
  background: var(--site-paper);
  border: 1px solid var(--site-line);
  border-radius: 2px;
  font: inherit;
  font-size: 0.84rem;
  line-height: 1.2;
  white-space: nowrap;
}

.pid-live-controls select option {
  padding: 3px 8px;
  font-size: 0.84rem;
  line-height: 1.2;
}

.pid-anti-windup-status {
  margin: 8px 0 0;
  color: var(--site-muted);
  font-size: 0.76rem;
  line-height: 1.45;
}

.control-section-label {
  display: block;
  margin-bottom: 10px;
  color: var(--site-muted);
  font-family: var(--site-mono);
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.pid-plant-explainer {
  padding: 12px 14px;
  border-left: 3px solid var(--site-teal);
  background: #f1faf9;
  color: var(--site-ink-soft);
  font-size: 0.78rem;
  line-height: 1.6;
}

.pid-plant-explainer strong {
  display: block;
  margin-bottom: 7px;
  color: var(--site-teal);
  font-size: 0.86rem;
}

.pid-equation {
  margin-bottom: 7px;
  padding: 7px 8px;
  overflow-wrap: anywhere;
  background: #ffffff;
  color: var(--site-ink);
  font-family: var(--site-mono);
  font-size: 0.72rem;
  font-weight: 700;
}

.pid-plant-explainer p {
  margin: 0;
}

.pid-plant-explainer p + p {
  margin-top: 8px;
}

.pid-oscillation-hint {
  color: var(--site-red);
}

.pid-presets {
  padding-top: 4px;
}

.preset-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 8px;
}

.preset-button,
.view-tab {
  min-height: 44px;
  border: 1px solid var(--site-line);
  border-radius: 4px;
  padding: 9px 10px;
  background: var(--site-wash);
  color: var(--site-ink-soft);
  cursor: pointer;
  font-family: var(--site-sans);
  font-size: 0.78rem;
  font-weight: 700;
  line-height: 1.3;
  touch-action: manipulation;
  transition: background-color 140ms ease, border-color 140ms ease, color 140ms ease;
}

.preset-button:hover,
.preset-button:focus-visible {
  border-color: var(--site-teal);
  background: #e8f6f4;
  color: var(--site-teal);
}

.preset-button:active,
.view-tab:active,
.reset-button:active {
  transform: translateY(1px);
}

.result-toolbar {
  align-items: center;
  gap: 16px;
}

.view-tabs {
  display: inline-flex;
  gap: 4px;
  padding: 4px;
  border: 1px solid var(--site-line);
  background: var(--site-wash);
}

.view-tab {
  min-height: 38px;
  border-color: transparent;
  padding: 7px 12px;
  background: transparent;
}

.view-tab.is-active,
.view-tab.is-active:hover {
  border-color: var(--site-ink);
  background: var(--site-ink);
  color: #ffffff;
}

.view-tab:focus-visible,
.preset-button:focus-visible {
  outline: 3px solid rgba(13, 148, 136, 0.45);
  outline-offset: 2px;
}

.pid-view.is-hidden {
  display: none;
}

.pid-time-view,
.pid-bode-view {
  min-width: 0;
}

.bode-model-note {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  align-items: baseline;
  margin-top: 18px;
  padding: 12px 14px;
  border-left: 3px solid var(--site-teal);
  background: #f1faf9;
  color: var(--site-ink-soft);
  font-size: 0.78rem;
  line-height: 1.5;
}

.bode-model-note strong {
  color: var(--site-teal);
  font-family: var(--site-mono);
  font-size: 0.7rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.bode-model-note span {
  font-family: var(--site-mono);
}

.bode-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 20px;
  margin: 16px 0 4px;
  color: var(--site-muted);
  font-size: 0.74rem;
}

.bode-legend span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
}

.legend-line {
  display: inline-block;
  width: 24px;
  border-top: 3px solid currentColor;
}

.legend-magnitude {
  color: var(--site-blue);
}

.legend-phase {
  color: #7357a6;
}

.legend-reference {
  border-top-style: dashed;
  color: var(--site-orange);
}

#pid-bode-magnitude-canvas,
#pid-bode-phase-canvas {
  display: block;
  width: 100%;
  height: auto;
  margin-top: 12px;
  background: #fbfdfe;
}

#pid-bode-phase-canvas {
  margin-top: 8px;
  border-top: 1px solid var(--site-line);
}

.bode-metrics {
  margin-top: 18px;
}

.bode-metrics > div {
  min-height: 68px;
}

.bode-metrics strong {
  color: var(--site-teal);
}

.bode-diagnosis,
.bode-boundary {
  margin: 18px 0 0;
  color: var(--site-ink-soft);
  font-size: 0.82rem;
  line-height: 1.7;
}

.bode-diagnosis {
  padding: 12px 14px;
  border-left: 3px solid var(--site-orange);
  background: #fff8ed;
}

.bode-boundary {
  color: var(--site-muted);
  font-size: 0.76rem;
}

.reset-button {
  border-color: var(--site-line);
  background: var(--site-wash);
  color: var(--site-ink);
  cursor: pointer;
}

.playground-result {
  min-width: 0;
  padding: 26px 30px 30px;
}

#pid-response-canvas {
  display: block;
  width: 100%;
  height: auto;
  min-height: 390px;
  margin-top: 8px;
  border-bottom: 1px solid var(--site-line);
  background: #fbfdfe;
}

.chart-section-label {
  margin: 18px 0 0;
  color: var(--site-ink-soft);
  font-family: var(--site-mono);
  font-size: 0.72rem;
  font-weight: 700;
  line-height: 1.5;
}

.time-chart-heading {
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  align-items: center;
  justify-content: space-between;
  margin-top: 16px;
}

.time-chart-heading .chart-section-label {
  margin-top: 0;
}

.time-chart-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 14px;
  color: var(--site-muted);
  font-size: 0.7rem;
}

.time-chart-legend span {
  display: inline-flex;
  align-items: center;
  gap: 6px;
}

.legend-control {
  color: var(--site-red);
}

.legend-p {
  border-top-style: dashed;
  color: var(--site-blue);
}

.legend-i {
  border-top-style: dotted;
  color: var(--site-teal);
}

.legend-d {
  border-top-style: dashed;
  color: var(--site-orange);
}

#pid-control-canvas {
  display: block;
  width: 100%;
  height: auto;
  min-height: 320px;
  margin-top: 8px;
  border-top: 1px solid var(--site-line);
  border-bottom: 1px solid var(--site-line);
  background: #fbfdfe;
}

.pid-component-heading {
  margin-top: 24px;
  padding-top: 18px;
  border-top: 1px solid var(--site-line);
}

.pid-series-controls {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 16px;
  align-items: center;
  margin-top: 18px;
  padding: 10px 12px;
  border: 1px solid var(--site-line);
  background: #ffffff;
  color: var(--site-muted);
  font-size: 0.76rem;
}

.pid-series-title,
.pid-series-group b {
  color: var(--site-ink-soft);
  font-family: var(--site-mono);
  font-size: 0.68rem;
  font-weight: 700;
}

.pid-series-group {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 6px 10px;
  align-items: center;
}

.pid-series-group label {
  display: inline-flex;
  gap: 4px;
  align-items: center;
  cursor: pointer;
}

.pid-series-group input {
  margin: 0;
  accent-color: var(--site-teal);
}

#pid-component-canvas {
  display: block;
  width: 100%;
  height: auto;
  min-height: 300px;
  margin-top: 8px;
  border-top: 1px solid var(--site-line);
  border-bottom: 1px solid var(--site-line);
  background: #fbfdfe;
}

.result-metrics {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0;
  margin-top: 18px;
}

.result-metrics > div {
  display: grid;
  gap: 6px;
  padding: 0 14px;
  border-right: 1px solid var(--site-line);
}

.result-metrics > div:first-child {
  padding-left: 0;
}

.result-metrics > div:last-child {
  border-right: 0;
}

.result-metrics span {
  color: var(--site-muted);
  font-size: 0.72rem;
}

.result-metrics strong {
  font-family: var(--site-mono);
  font-size: 0.92rem;
}

.playground-caption {
  width: min(1180px, calc(100% - 48px));
  margin: 14px auto 0;
  color: var(--site-muted);
  font-size: 0.82rem;
  line-height: 1.7;
}

.control-roadmap {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  border-top: 1px solid var(--site-line);
  border-bottom: 1px solid var(--site-line);
}

.roadmap-item {
  min-height: 170px;
  padding: 22px;
  border-right: 1px solid var(--site-line);
}

.roadmap-item:last-child {
  border-right: 0;
}

.roadmap-item-active {
  background: rgba(13, 148, 136, 0.07);
}

.roadmap-item strong {
  display: block;
  margin-top: 38px;
  font-size: 0.95rem;
  line-height: 1.4;
}

.roadmap-item p {
  margin: 8px 0 0;
  color: var(--site-muted);
  font-size: 0.8rem;
  line-height: 1.6;
}

.series-cta {
  margin-bottom: 26px;
}

.series-notes {
  margin-bottom: 82px;
  border-left: 3px solid var(--site-red);
  padding: 16px 18px;
  background: #fff8f7;
  color: var(--site-ink-soft);
  font-size: 0.88rem;
  line-height: 1.7;
}

.reference-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
  margin-bottom: 80px;
}

.tools-hero,
.lab-workbench-hero {
  display: grid;
  grid-template-columns: minmax(0, 1.1fr) minmax(300px, 0.9fr);
  gap: clamp(36px, 7vw, 96px);
  align-items: center;
  min-height: min(560px, calc(100vh - 56px));
  padding: clamp(64px, 9vw, 110px) 0 clamp(54px, 8vw, 88px);
}

.tools-hero-copy,
.lab-workbench-copy {
  max-width: 690px;
}

.tools-hero h1,
.lab-workbench-hero h1 {
  max-width: 12ch;
  margin: 0;
  color: var(--site-ink);
  font-size: clamp(2.8rem, 6vw, 5.8rem);
  font-weight: 800;
  line-height: 1;
  text-wrap: balance;
}

.tools-hero-copy > p:not(.eyebrow),
.lab-workbench-copy > p:not(.eyebrow) {
  max-width: 650px;
  margin: 28px 0 0;
  color: var(--site-ink-soft);
  font-size: clamp(1.05rem, 1.5vw, 1.28rem);
  line-height: 1.8;
}

.tools-hero-index {
  display: grid;
  grid-template-columns: 1fr auto 1fr auto 1fr;
  gap: 12px;
  align-items: center;
  min-height: 190px;
  padding: 26px;
  border-top: 2px solid var(--site-ink);
  border-bottom: 1px solid var(--site-line);
  background: var(--site-paper);
}

.tools-hero-index span {
  display: grid;
  gap: 8px;
}

.tools-hero-index strong {
  color: var(--site-teal);
  font-family: var(--site-mono);
  font-size: 0.82rem;
  letter-spacing: 0.08em;
}

.tools-hero-index small {
  color: var(--site-ink-soft);
  font-size: 0.86rem;
  line-height: 1.5;
}

.tools-hero-index b {
  color: var(--site-orange);
  font-family: var(--site-mono);
  font-size: 1.1rem;
}

.tool-catalog-grid,
.tool-evidence-strip,
.lab-step-strip,
.lab-resource-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0;
  border-top: 1px solid var(--site-line);
  border-bottom: 1px solid var(--site-line);
}

.tool-catalog-item,
.tool-evidence-strip > div,
.lab-step-strip > div,
.lab-resource-item {
  min-height: 240px;
  padding: 28px;
  border-right: 1px solid var(--site-line);
}

.tool-catalog-item:last-child,
.tool-evidence-strip > div:last-child,
.lab-step-strip > div:last-child,
.lab-resource-item:last-child {
  border-right: 0;
}

.tool-catalog-item-active {
  background: rgba(13, 148, 136, 0.07);
}

.tool-catalog-item h2,
.lab-resource-item h3,
.tool-evidence-strip h3,
.lab-step-strip strong {
  margin: 0;
  color: var(--site-ink);
  font-size: 1.22rem;
  line-height: 1.35;
}

.tool-catalog-item p:not(.eyebrow),
.lab-resource-item p:not(.eyebrow),
.tool-evidence-strip p,
.lab-step-strip p {
  margin: 10px 0 0;
  color: var(--site-muted);
  font-size: 0.88rem;
  line-height: 1.7;
}

.tool-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  margin: 18px 0 20px;
}

.tool-tags span {
  padding: 5px 8px;
  border: 1px solid rgba(13, 148, 136, 0.35);
  color: var(--site-teal);
  font-family: var(--site-mono);
  font-size: 0.68rem;
}

.tool-evidence-strip,
.lab-step-strip {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.tool-evidence-strip > div,
.lab-step-strip > div {
  min-height: 180px;
}

.tool-evidence-strip strong,
.lab-step-strip span {
  display: block;
  margin-bottom: 30px;
  color: var(--site-orange);
  font-family: var(--site-mono);
  font-size: 0.8rem;
  font-weight: 700;
}

.lab-workbench-status {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 8px 12px;
  align-content: center;
  min-height: 170px;
  padding: 28px;
  border-left: 3px solid var(--site-teal);
  background: #f1faf9;
  color: var(--site-muted);
  font-family: var(--site-mono);
  font-size: 0.78rem;
}

.lab-workbench-status .status-dot {
  grid-row: span 3;
  align-self: start;
  margin-top: 4px;
}

.lab-workbench-status strong {
  color: var(--site-teal);
  font-size: 0.86rem;
}

.lab-resource-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.lab-resource-item {
  min-height: 220px;
}

.lab-resource-item .btn-secondary {
  margin-top: 18px;
}

.lab-resource-item .text-link {
  display: block;
  margin-top: 12px;
}

.tool-boundary-note {
  margin-top: 42px;
  margin-bottom: 80px;
  border-left: 3px solid var(--site-red);
  padding: 16px 18px;
  background: #fff8f7;
  color: var(--site-ink-soft);
  font-size: 0.88rem;
  line-height: 1.7;
}

.tool-boundary-note strong {
  color: var(--site-red);
}

.reference-item {
  min-height: 220px;
}

@media (max-width: 980px) {
  .site-home-hero,
  .control-landing-hero {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .hero-signal,
  .control-hero-visual {
    min-height: 360px;
  }

  .hero-signal {
    min-height: 0;
  }

  .home-path,
  .control-roadmap {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .path-step:nth-child(2n),
  .roadmap-item:nth-child(2n) {
    border-right: 0;
  }

  .path-step:nth-child(n + 3),
  .roadmap-item:nth-child(n + 3) {
    border-top: 1px solid var(--site-line);
  }

  .control-stat-strip {
    grid-template-columns: repeat(2, 1fr);
  }

  .control-stat:nth-child(2n) {
    border-right: 0;
  }

  .control-stat:nth-child(n + 3) {
    border-top: 1px solid var(--site-line);
  }
}

@media (max-width: 760px) {
  .site-home-hero,
  .control-landing-hero,
  .home-metrics,
  .control-stat-strip,
  .home-path,
  .home-series-grid,
  .learning-promise,
  .pid-principles,
  .pid-playground,
  .control-roadmap,
  .series-cta,
  .series-notes,
  .reference-grid,
  .tools-hero,
  .tool-catalog-grid,
  .tool-evidence-strip,
  .lab-workbench-hero,
  .lab-step-strip,
  .lab-resource-grid,
  .tool-boundary-note,
  .page-layout-full main > h2,
  .page-layout-full main > p:not(.eyebrow) {
    width: 100%;
  }

  .site-home-hero,
  .control-landing-hero {
    padding-top: 36px;
    padding-bottom: 32px;
  }

  .site-home-hero h1,
  .control-landing-hero h1 {
    max-width: none;
    font-size: clamp(2.8rem, 14vw, 4.5rem);
  }

  .hero-signal,
  .control-hero-visual {
    min-height: 184px;
    box-shadow: 8px 8px 0 rgba(36, 91, 138, 0.09);
  }

  .hero-signal {
    min-height: 0;
  }

  .control-hero-copy > p:not(.eyebrow):not(.hero-footnote) {
    margin-top: 18px;
    font-size: 1rem;
    line-height: 1.65;
  }

  .control-hero-copy .hero-actions {
    margin-top: 22px;
  }

  .control-hero-copy .hero-footnote {
    margin-top: 18px;
  }

  .control-hero-visual {
    min-height: 340px;
    padding: 16px;
  }

  .home-metrics,
  .control-stat-strip,
  .home-path,
  .home-series-grid,
  .learning-promise,
  .pid-principles,
  .playground-layout,
  .control-roadmap,
  .reference-grid,
  .tool-catalog-grid,
  .tool-evidence-strip,
  .lab-step-strip,
  .lab-resource-grid {
    grid-template-columns: 1fr;
  }

  .metric,
  .control-stat,
  .path-step,
  .series-feature,
  .reference-item,
  .pid-principle,
  .roadmap-item {
    border-right: 0;
    border-bottom: 1px solid var(--site-line);
  }

  .metric:last-child,
  .control-stat:last-child,
  .path-step:last-child,
  .series-feature:last-child,
  .reference-item:last-child,
  .pid-principle:last-child,
  .roadmap-item:last-child,
  .tool-catalog-item:last-child,
  .tool-evidence-strip > div:last-child,
  .lab-step-strip > div:last-child,
  .lab-resource-item:last-child {
    border-bottom: 0;
  }

  .tool-catalog-item,
  .tool-evidence-strip > div,
  .lab-step-strip > div,
  .lab-resource-item {
    border-right: 0;
    border-bottom: 1px solid var(--site-line);
  }

  .tools-hero,
  .lab-workbench-hero {
    grid-template-columns: 1fr;
    min-height: auto;
    padding-top: 36px;
    padding-bottom: 32px;
  }

  .playground-heading {
    grid-template-columns: 1fr;
    gap: 18px;
    padding: 24px;
  }

  .tools-hero h1,
  .lab-workbench-hero h1 {
    max-width: none;
    font-size: clamp(2.8rem, 14vw, 4.5rem);
  }

  .tools-hero-copy > p:not(.eyebrow),
  .lab-workbench-copy > p:not(.eyebrow) {
    margin-top: 18px;
    font-size: 1rem;
    line-height: 1.65;
  }

  .tools-hero-index {
    min-height: 150px;
    padding: 20px;
  }

  .lab-workbench-status {
    min-height: 130px;
  }

  .path-step:nth-child(n + 3),
  .roadmap-item:nth-child(n + 3),
  .control-stat:nth-child(n + 3) {
    border-top: 0;
  }

  .path-step {
    min-height: 160px;
  }

  .path-index {
    margin-bottom: 28px;
  }

  .learning-promise,
  .playground-heading {
    gap: 26px;
  }

  .promise-list {
    grid-template-columns: 1fr;
  }

  .pid-principle {
    min-height: auto;
  }

  .playground-heading,
  .playground-controls,
  .playground-result {
    padding: 24px;
  }

  .playground-controls {
    position: static;
    max-height: none;
    overflow: visible;
    grid-template-columns: 1fr;
    border-right: 0;
    border-bottom: 1px solid var(--site-line);
  }

  .playground-controls > .pid-live-controls {
    grid-template-columns: 1fr;
  }

  .result-toolbar,
  .time-chart-heading {
    align-items: flex-start;
    flex-direction: column;
  }

  .view-tabs {
    width: 100%;
  }

  .view-tab {
    flex: 1 1 0;
  }

  .bode-model-note {
    align-items: flex-start;
    flex-direction: column;
  }

  .result-metrics {
    grid-template-columns: repeat(2, 1fr);
    gap: 18px 0;
  }

  .result-metrics > div:nth-child(2) {
    border-right: 0;
  }

  .result-metrics > div:nth-child(3) {
    padding-left: 0;
  }

  .control-loop-diagram {
    grid-template-columns: repeat(2, 1fr);
    gap: 10px;
    margin-top: 18px;
  }

  .control-hero-visual::before,
  .control-hero-visual::after {
    display: none;
  }

  .loop-block {
    min-height: 54px;
  }

  .loop-block span {
    font-size: 0.95rem;
  }

  .loop-block small {
    margin-top: 2px;
    font-size: 0.6rem;
  }

  .loop-arrow {
    display: none;
  }

  .loop-feedback {
    right: 16px;
    bottom: 112px;
    left: 16px;
    height: 42px;
  }

  .loop-feedback span {
    bottom: 5px;
    font-size: 0.62rem;
  }

  .loop-feedback b {
    top: -10px;
    font-size: 0.6rem;
  }

  .hero-plot {
    right: 16px;
    bottom: 16px;
    left: 16px;
    height: 82px;
  }

  .series-cta,
  .home-footer-callout {
    align-items: flex-start;
    flex-direction: column;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }

  .plot-response-path {
    stroke-dashoffset: 0;
  }
}