:root {
  color-scheme: light;
  --brand: #0b4ea2;
  --brand-ink: #ffffff;
  --accent: #f2c400;
  --page: #f6f7f9;
  --surface: #ffffff;
  --text: #0f1720;
  --text-2: #4a5563;
  --muted: #7b8591;
  --grid: #e4e7ec;
  --axis: #c3c9d2;
  --border: #d9dee5;
  --series-1: #2a78d6;
  --series-2: #eb6834;
  --series-3: #1baf7a;
  --link: #0b4ea2;
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --brand: #0a3b7c;
    --page: #0e1116;
    --surface: #171b22;
    --text: #f4f6f8;
    --text-2: #b8c0cb;
    --muted: #8590a0;
    --grid: #262c36;
    --axis: #3a4250;
    --border: #2a313c;
    --series-1: #3987e5;
    --series-2: #d95926;
    --series-3: #199e70;
    --link: #8fbcf5;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--page);
  color: var(--text);
  font: 17px/1.55 system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  -webkit-text-size-adjust: 100%;
}

a {
  color: var(--link);
  text-underline-offset: 0.15em;
}

a:hover {
  text-decoration-thickness: 2px;
}

main,
.bar {
  max-width: 1000px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Header: the Region's blue, with a yellow rule beneath */

.top {
  background: var(--brand);
  color: var(--brand-ink);
  border-bottom: 4px solid var(--accent);
}

.top .bar {
  display: flex;
  align-items: center;
  gap: 10px 12px;
  flex-wrap: wrap;
  padding-top: 14px;
  padding-bottom: 14px;
}

.mark {
  flex: none;
  width: 22px;
  height: 22px;
  fill: var(--accent);
}

h1 {
  margin: 0;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: -0.005em;
}

.tag {
  padding: 1px 8px;
  border: 1px solid rgba(255, 255, 255, 0.55);
  border-radius: 999px;
  font-size: 0.75rem;
  white-space: nowrap;
}

.lang {
  display: flex;
  gap: 2px;
  margin-left: auto;
  font-size: 0.85rem;
  font-weight: 600;
}

.lang a,
.lang span {
  padding: 2px 8px;
  border-radius: 4px;
  color: var(--brand-ink);
}

.lang span {
  background: rgba(255, 255, 255, 0.18);
}

/* Headings and text */

section {
  margin: 56px 0;
}

.intro {
  margin-top: 40px;
}

.eyebrow {
  margin: 0 0 6px;
  color: var(--link);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

h2 {
  margin: 0 0 16px;
  font-size: 1.5rem;
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.015em;
}

.intro h2 {
  margin-bottom: 8px;
  font-size: 1.75rem;
}

.lead {
  margin: 0 0 12px;
  max-width: 62ch;
  color: var(--text-2);
  font-size: 1.05rem;
}

.meta,
.notice {
  margin: 0 0 20px;
  max-width: 78ch;
  color: var(--text-2);
  font-size: 0.9rem;
}

.meta span::before {
  content: "·";
  margin: 0 8px;
}

.notice {
  margin-top: 16px;
  padding: 10px 14px;
  border-left: 4px solid var(--accent);
  background: var(--surface);
  color: var(--text);
}

.card,
.tile {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 6px;
}

.card {
  padding: 20px;
}

.card + .card {
  margin-top: 16px;
}

/* The prices in force: one card per fuel, marked with the fuel's colour */

.tiles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.tile {
  display: flex;
  flex-direction: column;
  padding: 18px 20px 16px;
  border-top-width: 4px;
}

.t1 {
  border-top-color: var(--series-1);
}

.t2 {
  border-top-color: var(--series-2);
}

.t3 {
  border-top-color: var(--series-3);
}

.tile h3 {
  margin: 0;
  color: var(--text-2);
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.price {
  margin: 10px 0 16px;
  font-size: 2.7rem;
  font-weight: 700;
  line-height: 1;
  letter-spacing: -0.02em;
}

.price span {
  display: block;
  margin-top: 6px;
  color: var(--text-2);
  font-size: 0.85rem;
  font-weight: 400;
  letter-spacing: 0;
}

.changes {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  margin: 0;
  padding: 12px 0;
  border-top: 1px solid var(--grid);
  font-variant-numeric: tabular-nums;
}

.changes dt,
.next span {
  color: var(--text-2);
  font-size: 0.75rem;
}

.changes dd {
  margin: 2px 0 0;
}

.changes strong {
  display: block;
  font-size: 0.95rem;
  white-space: nowrap;
}

small {
  color: var(--text-2);
  font-size: 0.8rem;
  font-variant-numeric: tabular-nums;
}

.next {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  gap: 0 8px;
  margin: auto 0 0;
  padding-top: 12px;
  border-top: 1px solid var(--grid);
}

.next span {
  flex-basis: 100%;
}

.next strong {
  font-size: 1.15rem;
}

/* History charts: each is drawn for a wide and for a narrow screen */

.chart-head {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 4px 16px;
  margin-bottom: 12px;
}

.chart-head h3 {
  margin: 0;
  font-size: 1rem;
  font-weight: 700;
}

.legend {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 16px;
}

.legend span {
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--text-2);
  font-size: 0.85rem;
}

.key {
  flex: none;
  width: 16px;
  height: 2px;
  border-radius: 1px;
}

.s1 {
  background: var(--series-1);
}

.s2 {
  background: var(--series-2);
}

.s3 {
  background: var(--series-3);
}

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

.chart .narrow {
  display: none;
}

.chart text {
  fill: var(--muted);
  font-size: 12px;
  font-variant-numeric: tabular-nums;
}

.chart text.end {
  fill: var(--text);
  font-weight: 600;
}

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

.chart .base {
  stroke: var(--axis);
  stroke-width: 1;
}

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

.chart .l1 {
  stroke: var(--series-1);
}

.chart .l2 {
  stroke: var(--series-2);
}

.chart .l3 {
  stroke: var(--series-3);
}

.chart circle {
  stroke: var(--surface);
  stroke-width: 2;
}

.chart .f1 {
  fill: var(--series-1);
}

.chart .f2 {
  fill: var(--series-2);
}

.chart .f3 {
  fill: var(--series-3);
}

/* Footer: the header's colours again, to close the page */

footer {
  margin-top: 72px;
  padding: 36px 0 28px;
  border-top: 4px solid var(--accent);
  background: var(--brand);
  color: var(--brand-ink);
  font-size: 0.9rem;
}

footer .bar {
  display: grid;
  grid-template-columns: 3fr 2fr;
  gap: 28px 56px;
}

footer h2 {
  margin: 0 0 8px;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

footer p {
  margin: 0;
  max-width: 60ch;
  opacity: 0.92;
}

footer ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

footer li + li {
  margin-top: 6px;
}

footer a {
  color: var(--brand-ink);
}

footer .fine {
  grid-column: 1 / -1;
  max-width: none;
  padding-top: 18px;
  border-top: 1px solid rgba(255, 255, 255, 0.25);
  font-size: 0.8rem;
  opacity: 0.8;
}

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

  .intro h2 {
    font-size: 1.2rem;
  }

  h2 {
    font-size: 1.2rem;
  }

  h1 {
    font-size: 0.9rem;
  }

  .top .bar {
    flex-wrap: nowrap;
    gap: 8px;
    padding-top: 8px;
    padding-bottom: 8px;
  }

  .mark {
    width: 18px;
    height: 18px;
  }

  /* No room for the tag beside the name; the footer says the same. */
  .tag {
    display: none;
  }

  section {
    margin: 40px 0;
  }

  .intro {
    margin-top: 28px;
  }

  footer .bar {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 600px) {
  .chart .wide {
    display: none;
  }

  .chart .narrow {
    display: block;
  }

  .card {
    padding: 16px;
  }

}