/* Exu explainer: an instrument panel, not a brochure.
   Palette: deep indigo base, one teal signal color for measurement, amber for
   uncertainty. Type: a characterful grotesk for display, a quiet humanist for
   body, a mono for every number. */

:root {
  --bg: #0f1424;
  --bg-2: #131a2e;
  --panel: #161c30;
  --panel-2: #1c2440;
  --line: #2b3454;
  --line-soft: #232b47;
  --ink: #e9edf9;
  --muted: #9aa4c2;
  --dim: #848fae;
  --signal: #46d3c4;
  --signal-2: #86e6dc;
  --warn: #f5a524;
  --alarm: #ff7a7a;

  --display: "Familjen Grotesk", "Helvetica Neue", sans-serif;
  --body: "Public Sans", system-ui, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, monospace;

  --gap: clamp(1rem, 2.5vw, 2rem);
  --radius: 4px;
  --max: 1120px;
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--body);
  font-size: 17px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  background-image: radial-gradient(circle at 15% -10%, rgba(70, 211, 196, 0.08), transparent 45%),
    radial-gradient(circle at 90% 0%, rgba(245, 165, 36, 0.06), transparent 40%);
  background-repeat: no-repeat;
}

h1,
h2,
h3 {
  font-family: var(--display);
  font-weight: 600;
  line-height: 1.1;
  margin: 0;
  letter-spacing: -0.02em;
}

h1 {
  font-size: clamp(2.6rem, 7vw, 4.6rem);
}

h2 {
  font-size: clamp(1.6rem, 3.4vw, 2.4rem);
  max-width: 22ch;
}

p {
  margin: 0;
}

a {
  color: var(--signal);
  text-decoration-color: rgba(70, 211, 196, 0.35);
  text-underline-offset: 3px;
}

a:hover {
  color: var(--signal-2);
  text-decoration-color: currentColor;
}

:focus-visible {
  outline: 2px solid var(--signal);
  outline-offset: 3px;
  border-radius: 2px;
}

.mono {
  font-family: var(--mono);
  font-size: 0.86em;
  letter-spacing: -0.01em;
}

.small {
  font-size: 0.8rem;
}

.skip {
  position: absolute;
  left: -999px;
  top: 0;
  padding: 0.6rem 1rem;
  background: var(--signal);
  color: var(--bg);
  z-index: 10;
}

.skip:focus {
  left: 1rem;
  top: 1rem;
}

/* ------------------------------------------------------------------ header */

.masthead {
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(3rem, 9vw, 7rem) var(--gap) clamp(2rem, 5vw, 3rem);
  position: relative;
}

.eyebrow {
  font-family: var(--mono);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--dim);
  display: flex;
  align-items: center;
  gap: 0.7rem;
  margin-bottom: 1.4rem;
}

.eyebrow .num {
  color: var(--signal);
}

.eyebrow .dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--warn);
  box-shadow: 0 0 0 3px rgba(245, 165, 36, 0.15);
}

.lead {
  margin-top: 1.6rem;
  max-width: 58ch;
  font-size: clamp(1rem, 1.6vw, 1.2rem);
  color: var(--muted);
}

.lead strong {
  color: var(--ink);
  font-weight: 500;
}

.masthead-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.7rem;
  margin-top: 2rem;
}

.button {
  font-family: var(--mono);
  font-size: 0.8rem;
  letter-spacing: 0.02em;
  padding: 0.7rem 1.1rem;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  color: var(--ink);
  cursor: pointer;
  transition: border-color 0.15s, background 0.15s, transform 0.15s;
}

.button:hover {
  border-color: var(--signal);
  color: var(--ink);
  transform: translateY(-1px);
}

.button.primary {
  background: var(--signal);
  border-color: var(--signal);
  color: #08201e;
  font-weight: 500;
}

.button.primary:disabled {
  background: var(--panel-2);
  border-color: var(--line);
  color: var(--dim);
  cursor: not-allowed;
  transform: none;
}

.button.ghost {
  background: transparent;
}

.readout {
  margin-top: clamp(2.5rem, 6vw, 4rem);
  border-top: 1px solid var(--line-soft);
  padding-top: 1rem;
  display: flex;
  align-items: center;
  gap: 1.2rem;
}

.readout-label {
  font-family: var(--mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--dim);
  white-space: nowrap;
}

.readout-bars {
  display: flex;
  gap: 4px;
  align-items: flex-end;
  height: 34px;
  flex: 1;
}

.readout-bars span {
  display: block;
  width: 100%;
  background: var(--signal);
  opacity: 0.75;
  border-radius: 1px 1px 0 0;
  transition: height 0.6s cubic-bezier(0.22, 1, 0.36, 1);
}

/* ---------------------------------------------------------------- sections */

.section {
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(3rem, 8vw, 6rem) var(--gap);
  border-top: 1px solid var(--line-soft);
}

.section .body {
  margin-top: 1.4rem;
  max-width: 62ch;
  color: var(--muted);
}

.section h2 + .body {
  margin-top: 1.6rem;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: clamp(1.1rem, 2.4vw, 1.8rem);
}

.demo {
  margin-top: 2.2rem;
}

.demo-head {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem 1.4rem;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.4rem;
}

.demo-title {
  font-family: var(--display);
  font-size: 1.02rem;
  font-weight: 500;
}

.demo-hint {
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--dim);
}

.label {
  font-family: var(--mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--dim);
  display: block;
  margin-bottom: 0.6rem;
}

.caption {
  margin-top: 1.2rem;
  font-size: 0.9rem;
  color: var(--dim);
  border-top: 1px solid var(--line-soft);
  padding-top: 0.9rem;
}

/* ----------------------------------------------------------------- charts */

.chart {
  width: 100%;
  height: auto;
  display: block;
  overflow: visible;
}

.chart-grid line {
  stroke: var(--line-soft);
  stroke-width: 1;
}

.chart-grid text,
.chart-optimum {
  fill: var(--dim);
  font-family: var(--mono);
  font-size: 10px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.chart-area {
  fill: rgba(70, 211, 196, 0.09);
  stroke: none;
}

.chart-line,
.chart-step {
  fill: none;
  stroke-width: 2;
  stroke-linejoin: round;
}

.chart-line {
  stroke: var(--signal);
}

.chart-step {
  stroke: var(--alarm);
  stroke-dasharray: 5 4;
}

.chart-rule {
  stroke: var(--line);
  stroke-width: 1;
}

.chart-node {
  fill: var(--bg);
  stroke: var(--signal);
  stroke-width: 2;
}

.chart-node.bad {
  stroke: var(--alarm);
}

/* ---------------------------------------------------------------- controls */

.demo-controls {
  margin-top: 1.4rem;
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
}

.slider {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 0.3rem 1rem;
  align-items: center;
  width: 100%;
}

.slider compact,
.slider.compact {
  width: auto;
}

.slider-label {
  grid-column: 1 / -1;
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--muted);
}

.slider output {
  color: var(--signal);
  min-width: 4ch;
  text-align: right;
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 4px;
  background: var(--line);
  border-radius: 2px;
  cursor: pointer;
  grid-column: 1;
}

input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--signal);
  border: 3px solid var(--bg);
  box-shadow: 0 0 0 1px var(--signal);
}

input[type="range"]::-moz-range-thumb {
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--signal);
  border: 3px solid var(--bg);
}

.slider.compact {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.slider.compact input[type="range"] {
  width: 110px;
}

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(130px, 1fr));
  gap: 1px;
  margin: 1.4rem 0 0;
  background: var(--line-soft);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  overflow: hidden;
}

.stats > div {
  background: var(--panel);
  padding: 0.8rem 1rem;
}

.stats dt {
  font-family: var(--mono);
  font-size: 0.68rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--dim);
}

.stats dd {
  margin: 0.35rem 0 0;
  font-size: 1.05rem;
  color: var(--signal);
}

/* ---------------------------------------------------------------- tabs and segments */

.tabs,
.segmented {
  display: inline-flex;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  overflow: hidden;
  margin-bottom: 1.4rem;
}

.tab,
.seg {
  font-family: var(--mono);
  font-size: 0.78rem;
  padding: 0.5rem 1rem;
  background: transparent;
  border: 0;
  border-right: 1px solid var(--line);
  color: var(--muted);
  cursor: pointer;
}

.tab:last-child,
.seg:last-child {
  border-right: 0;
}

.tab[aria-selected="true"],
.seg[aria-pressed="true"] {
  background: var(--signal);
  color: #08201e;
}

/* --------------------------------------------------------------- primitives */

.primitive {
  display: grid;
  gap: 1.3rem;
}

.state {
  color: var(--ink);
  background: var(--panel-2);
  border-left: 2px solid var(--signal);
  padding: 0.6rem 0.9rem;
  border-radius: 0 3px 3px 0;
}

#prim-question {
  color: var(--muted);
}

.dist {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}

.dist-row {
  display: grid;
  grid-template-columns: minmax(5rem, 12rem) 1fr auto;
  gap: 0.8rem;
  align-items: center;
  font-family: var(--mono);
  font-size: 0.8rem;
}

.dist-name {
  color: var(--muted);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.dist-track {
  height: 8px;
  background: var(--panel-2);
  border-radius: 2px;
  overflow: hidden;
}

.dist-fill {
  height: 100%;
  background: var(--signal);
  border-radius: 2px;
  transition: width 0.5s cubic-bezier(0.22, 1, 0.36, 1);
}

.dist-value {
  color: var(--ink);
  min-width: 5ch;
  text-align: right;
}

.dist.large .dist-track {
  height: 14px;
}

/* ------------------------------------------------------------------- tape */

.tape {
  display: flex;
  flex-wrap: wrap;
  gap: 3px;
  padding: 0.9rem;
  background: var(--bg-2);
  border: 1px solid var(--line-soft);
  border-radius: var(--radius);
  font-family: var(--mono);
  font-size: 0.72rem;
}

.token {
  padding: 0.3rem 0.5rem;
  border-radius: 2px;
  background: var(--panel-2);
  color: var(--muted);
  white-space: nowrap;
}

.token.special {
  background: transparent;
  color: var(--dim);
  padding-inline: 0.25rem;
}

/* The type prefix words. Not `.label`: that class is a display block, so sharing
   it broke these chips onto one line each. */
.token.prefix {
  background: transparent;
  color: var(--muted);
  padding-inline: 0.25rem;
}

.token.marker {
  background: rgba(70, 211, 196, 0.16);
  color: var(--signal);
  box-shadow: inset 0 0 0 1px rgba(70, 211, 196, 0.4);
}

.token.option {
  background: rgba(245, 165, 36, 0.12);
  color: #f7c877;
}

.token.instruction {
  background: rgba(70, 211, 196, 0.08);
  color: var(--signal-2);
}

.token.state {
  background: var(--panel);
  color: var(--dim);
}

.budget {
  margin-top: 1.3rem;
}

.budget-bar {
  display: flex;
  height: 10px;
  border-radius: 2px;
  overflow: hidden;
  background: var(--panel-2);
}

.budget-bar span {
  display: block;
  transition: width 0.4s cubic-bezier(0.22, 1, 0.36, 1);
}

.legend {
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1.2rem;
  padding: 0;
  margin: 0.9rem 0 0;
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--dim);
}

.legend li {
  display: flex;
  align-items: center;
  gap: 0.45rem;
}

.swatch {
  width: 10px;
  height: 10px;
  border-radius: 2px;
  display: inline-block;
}

/* ----------------------------------------------------------------- policy */

.policy {
  display: grid;
  gap: 1.6rem;
  grid-template-columns: 1fr;
}

@media (min-width: 760px) {
  .policy {
    grid-template-columns: 1fr 1fr;
  }
}

.candidates {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(64px, 1fr));
  gap: 6px;
}

.candidate {
  border: 1px solid var(--line-soft);
  border-radius: 3px;
  padding: 0.4rem;
  background: var(--bg-2);
}

.candidate .mini {
  display: flex;
  gap: 2px;
  align-items: flex-end;
  height: 40px;
}

.candidate .mini span {
  flex: 1;
  background: var(--dim);
  border-radius: 1px 1px 0 0;
}

.candidate.win .mini span {
  background: var(--signal);
}

.candidate.lose .mini span {
  background: var(--line);
}

.candidate-reward {
  display: block;
  margin-top: 0.35rem;
  font-family: var(--mono);
  font-size: 0.66rem;
  color: var(--dim);
  text-align: center;
}

.candidate.win .candidate-reward {
  color: var(--signal);
}

.tally {
  color: var(--dim);
  font-size: 0.78rem;
}

/* -------------------------------------------------------------- do-it grid */

.two-col {
  display: grid;
  gap: 1rem;
  margin-top: 2.2rem;
}

@media (min-width: 840px) {
  .two-col {
    grid-template-columns: 1fr 1fr;
  }
}

.code {
  margin: 0;
  overflow-x: auto;
  font-family: var(--mono);
  font-size: 0.74rem;
  line-height: 1.75;
  color: var(--muted);
}

.code code {
  white-space: pre;
}

.checklist-panel {
  margin-top: 1rem;
}

.checklist {
  list-style: none;
  counter-reset: step;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.7rem;
}

.checklist li {
  counter-increment: step;
  display: grid;
  grid-template-columns: 2.2rem 1fr;
  gap: 0.8rem;
  align-items: baseline;
  color: var(--muted);
  font-size: 0.92rem;
}

.checklist li::before {
  content: counter(step, decimal-leading-zero);
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--signal);
  border-bottom: 1px solid var(--line-soft);
  padding-bottom: 0.2rem;
}

/* ----------------------------------------------------------------- footer */

.footer {
  max-width: var(--max);
  margin: 0 auto;
  padding: clamp(2.5rem, 6vw, 4rem) var(--gap) 4rem;
  border-top: 1px solid var(--line-soft);
  display: grid;
  gap: 2rem;
}

@media (min-width: 760px) {
  .footer {
    grid-template-columns: 2fr 1fr 1fr;
  }
}

.footer p {
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 0.5rem;
  max-width: 40ch;
}

.footer ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 0.4rem;
  font-size: 0.9rem;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}