:root {
  --ink: #15202b;
  --muted: #5c6672;
  --line: #d5dbe3;
  --panel: #f3f6f8;
  --accent: #1f4e5f;
  --air: #0b6e4f;
  --link: #c45c26;
  --metro: #6b5b95;
  --font: "IBM Plex Sans", "Helvetica Neue", sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, monospace;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  min-height: 100%;
  font-family: var(--font);
  color: var(--ink);
  background: #e4eaef;
}

a { color: var(--accent); }

.shell {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
}

.top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-shrink: 0;
  padding: 0.55rem 1rem;
  background: #fff;
  border-bottom: 1px solid var(--line);
}

.top__brand {
  display: flex;
  flex-direction: column;
  gap: 0.02rem;
}

.top__brand a {
  font-size: 0.72rem;
  font-weight: 600;
  text-decoration: none;
  color: var(--muted);
}

.top__brand strong {
  font-size: 1.05rem;
  letter-spacing: -0.03em;
}

.tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}

.tabs a {
  appearance: none;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 8px;
  padding: 0.38rem 0.7rem;
  font: inherit;
  font-size: 0.8rem;
  font-weight: 600;
  text-decoration: none;
  color: var(--ink);
}

.tabs a.is-on {
  background: var(--ink);
  border-color: var(--ink);
  color: #fff;
}

.insights {
  flex: 1;
  overflow: auto;
  background: #eef2f5;
}

.insights__inner {
  max-width: 920px;
  margin: 0 auto;
  padding: 1.25rem 1.1rem 3rem;
}

.insights__head h1,
.outliers h2,
.glossary h2,
.sources h2,
.block h2 {
  margin: 0;
  letter-spacing: -0.03em;
}

.insights__head p,
.chart-note,
.caveat,
.glossary > p,
.outliers__lead {
  margin: 0.4rem 0 0.85rem;
  color: var(--muted);
  line-height: 1.45;
  max-width: 46rem;
}

.hero {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 1rem 1.1rem 1.15rem;
  margin: 1rem 0 1.1rem;
}

.hero__kicker {
  margin: 0;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

.hero__stat {
  margin: 0.2rem 0 0;
  font-family: var(--mono);
  font-size: clamp(1.8rem, 5vw, 2.6rem);
  letter-spacing: -0.04em;
  color: var(--accent);
}

.hero__sub {
  margin: 0.15rem 0 0;
  font-family: var(--mono);
  font-size: 1.05rem;
}

.hero__note {
  margin: 0.55rem 0 0;
  color: var(--muted);
  line-height: 1.45;
  max-width: 44rem;
}

.controls {
  display: grid;
  grid-template-columns: 1fr 1fr;
  grid-template-areas:
    "drive drive"
    "miles eff"
    "park park";
  column-gap: 1.2rem;
  row-gap: 0.75rem;
  margin-bottom: 0.9rem;
  align-items: start;
}

.drive {
  grid-area: drive;
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
}
.control--miles { grid-area: miles; }
.control--eff { grid-area: eff; }

.control {
  display: grid;
  grid-template-rows: 2.5em auto 1.4em 2.7em;
  gap: 0.2rem;
  font-size: 0.78rem;
  font-weight: 600;
  color: var(--muted);
}

.control__name {
  display: flex;
  align-items: flex-end;
  line-height: 1.25;
}

.controls input[type="range"] {
  width: 100%;
  margin: 0;
  align-self: center;
}

.controls output {
  font-family: var(--mono);
  color: var(--ink);
  font-size: 0.9rem;
  line-height: 1.4em;
}

.control-note {
  font-size: 0.72rem;
  font-weight: 400;
  line-height: 1.35;
  color: var(--muted);
}

.drive button {
  appearance: none;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 8px;
  padding: 0.32rem 0.65rem;
  font: inherit;
  font-size: 0.78rem;
  font-weight: 600;
  cursor: pointer;
}

.drive button.is-on {
  background: var(--ink);
  border-color: var(--ink);
  color: #fff;
}

.controls .check {
  display: flex;
  align-items: center;
  gap: 0.45rem;
  grid-area: park;
  font-weight: 600;
  color: var(--ink);
}

.modes {
  display: flex;
  flex-wrap: wrap;
  gap: 0.35rem;
  margin-bottom: 0.7rem;
}

.modes button {
  appearance: none;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 8px;
  padding: 0.38rem 0.7rem;
  font: inherit;
  font-size: 0.8rem;
  font-weight: 600;
  cursor: pointer;
}

.modes button.is-on {
  background: var(--ink);
  border-color: var(--ink);
  color: #fff;
}

.stack {
  display: grid;
  gap: 0.35rem;
  margin: 0.7rem 0 1rem;
}

.stack-row {
  display: grid;
  grid-template-columns: minmax(8rem, 13.5rem) 1fr 5.2rem;
  gap: 0.5rem;
  align-items: center;
  font-size: 0.82rem;
}

.stack-row span {
  line-height: 1.25;
}

.stack-row i {
  display: block;
  height: 10px;
  border-radius: 99px;
  background: #e2e8ee;
  overflow: hidden;
}

.stack-row i b {
  display: block;
  height: 100%;
  border-radius: 99px;
  background: var(--air);
}

.stack-row em {
  font-style: normal;
  font-family: var(--mono);
  text-align: right;
}

.table-wrap {
  overflow-x: auto;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
}

.data-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.84rem;
}

.data-table th,
.data-table td {
  padding: 0.45rem 0.65rem;
  text-align: left;
  border-bottom: 1px solid var(--line);
}

.data-table th {
  font-size: 0.68rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--muted);
}

.data-table td:nth-child(2),
.data-table td:last-child,
.data-table th:nth-child(2),
.data-table th:last-child {
  text-align: right;
  font-family: var(--mono);
}

.stack-row a {
  color: inherit;
  text-decoration: underline;
  text-decoration-style: dotted;
  text-underline-offset: 0.15em;
}

.data-table a {
  color: inherit;
}

.glossary,
.outliers,
.sources,
.block {
  margin-top: 2.1rem;
  scroll-margin-top: 0.75rem;
}

.block__note {
  margin: 0.35rem 0 0.85rem;
  color: var(--muted);
  line-height: 1.45;
  max-width: 46rem;
}

.block .term {
  margin-top: 0.7rem;
}

.term p a {
  color: var(--accent);
}

.toc {
  display: flex;
  flex-wrap: wrap;
  gap: 0.45rem 0.85rem;
  margin: 0 0 0.4rem;
  padding: 0;
  list-style: none;
  font-size: 0.86rem;
  font-weight: 600;
}

.glossary__list {
  display: grid;
  gap: 0.7rem;
  margin-top: 0.7rem;
}

.term {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.85rem 1rem 1rem;
  scroll-margin-top: 0.75rem;
}

.term.is-in {
  border-color: #b7c4ce;
  box-shadow: inset 3px 0 0 var(--air);
}

.term__kicker {
  margin: 0;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
}

.term h3 {
  margin: 0.2rem 0 0;
  font-size: 1.02rem;
  letter-spacing: -0.02em;
}

.term p:last-child {
  margin: 0.4rem 0 0;
  font-size: 0.86rem;
  color: var(--muted);
  line-height: 1.45;
}

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 0.75rem;
  margin-top: 0.7rem;
}

.card {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 0.9rem 1rem 1rem;
}

.card__kicker {
  margin: 0;
  font-size: 0.68rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}

.card h3 {
  margin: 0.25rem 0 0;
  font-size: 1.02rem;
  letter-spacing: -0.02em;
}

.card__stat {
  margin: 0.35rem 0 0.45rem;
  font-family: var(--mono);
  font-size: 1.35rem;
  color: var(--accent);
}

.card p:last-child {
  margin: 0;
  font-size: 0.86rem;
  color: var(--muted);
  line-height: 1.45;
}

.source-files {
  margin: 0.4rem 0 0;
  padding-left: 1.1rem;
  color: var(--muted);
  line-height: 1.5;
}

.caveat {
  margin-top: 1.2rem;
}

@media (max-width: 640px) {
  .top {
    flex-wrap: wrap;
    align-items: flex-start;
  }
  .tabs a {
    font-size: 0.72rem;
    padding: 0.32rem 0.55rem;
  }
  .controls {
    grid-template-columns: 1fr;
    grid-template-areas:
      "drive"
      "miles"
      "eff"
      "park";
  }
  .control {
    grid-template-rows: auto auto 1.4em auto;
  }
  .stack-row { grid-template-columns: 1fr 4.6rem; }
  .stack-row span { grid-column: 1 / -1; }
}