/* Ariefz History additions: industrial chronology and sourced population chart. */
.history-back {
  color: var(--ink-2);
  font: 600 .72rem/1 var(--mono);
  letter-spacing: .12em;
  text-decoration: none;
  text-transform: uppercase;
  transition: color .2s ease;
}

.history-back:hover,
.history-back:focus-visible { color: var(--gold); }
.history-back:focus-visible,
.industrial-era:focus-visible { outline: 2px solid var(--gold); outline-offset: 4px; }

.industrial-section {
  background:
    radial-gradient(circle at 15% 20%, rgba(231,111,81,.09), transparent 34%),
    linear-gradient(180deg, transparent, rgba(230,180,80,.035), transparent);
}

.industrial-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin-top: 38px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

.industrial-era {
  position: relative;
  min-width: 0;
  padding: 30px 24px 28px;
  border-right: 1px solid var(--line);
  cursor: pointer;
  transition: background .25s ease, transform .25s ease;
}

.industrial-era:last-child { border-right: 0; }
.industrial-era:hover,
.industrial-era.is-active {
  background: linear-gradient(180deg, rgba(230,180,80,.10), rgba(255,255,255,.025));
  transform: translateY(-4px);
}

.industrial-number {
  display: block;
  color: var(--gold);
  font: 700 clamp(2.6rem, 5vw, 4.4rem)/.9 var(--serif);
}

.industrial-era time {
  display: block;
  margin-top: 20px;
  color: var(--cyan);
  font: 600 .7rem/1 var(--mono);
  letter-spacing: .12em;
  text-transform: uppercase;
}

.industrial-era h3 {
  margin-top: 12px;
  font: 700 1.35rem/1.15 var(--serif);
}

.industrial-era p {
  margin-top: 14px;
  color: var(--ink-2);
  font-size: .86rem;
}

.industrial-era ul {
  display: grid;
  gap: 7px;
  margin-top: 20px;
  list-style: none;
}

.industrial-era li {
  color: var(--ink-3);
  font: 500 .68rem/1.4 var(--mono);
  letter-spacing: .06em;
  text-transform: uppercase;
}

.industrial-era li::before { content: '+ '; color: var(--gold); }

.industrial-detail {
  display: grid;
  grid-template-columns: minmax(170px, .55fr) minmax(260px, 1fr) minmax(300px, 1.4fr);
  gap: 24px;
  align-items: start;
  padding: 28px 0 0;
}

.industrial-detail-label {
  color: var(--ink-3);
  font: 600 .7rem/1.4 var(--mono);
  letter-spacing: .14em;
  text-transform: uppercase;
}

.industrial-detail strong { font: 700 1.3rem/1.25 var(--serif); }
.industrial-detail p { color: var(--ink-2); font-size: .9rem; }

.population-section {
  background:
    radial-gradient(circle at 80% 20%, rgba(76,201,240,.08), transparent 34%),
    var(--bg-2);
}

.population-card {
  margin-top: 38px;
  padding: clamp(20px, 3.4vw, 38px);
  border: 1px solid var(--line);
  border-radius: 22px;
  background: var(--panel);
  box-shadow: 0 30px 80px -44px #000;
}

.population-readout {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  border-bottom: 1px solid var(--line);
}

.population-readout > div { padding: 0 20px 20px; border-right: 1px solid var(--line); }
.population-readout > div:first-child { padding-left: 0; }
.population-readout > div:last-child { border-right: 0; }
.population-readout span {
  display: block;
  color: var(--ink-3);
  font: 600 .66rem/1 var(--mono);
  letter-spacing: .12em;
  text-transform: uppercase;
}
.population-readout strong {
  display: block;
  margin-top: 11px;
  color: var(--gold-2);
  font: 700 clamp(1.2rem, 2.5vw, 2rem)/1.1 var(--serif);
}

.population-chart-wrap { margin-top: 28px; overflow-x: auto; }
.population-chart { display: block; width: 100%; min-width: 680px; height: auto; overflow: visible; }
.population-grid-line { stroke: rgba(255,255,255,.09); stroke-width: 1; }
.population-axis-label { fill: var(--ink-3); font: 24px var(--mono); }
.population-history-line,
.population-projection-line { fill: none; stroke-width: 7; stroke-linecap: round; stroke-linejoin: round; }
.population-history-line { stroke: var(--gold); }
.population-projection-line { stroke: var(--cyan); stroke-dasharray: 18 16; }
.population-area { fill: url(#populationArea); }
.population-cursor { stroke: rgba(255,255,255,.5); stroke-width: 2; stroke-dasharray: 7 7; }
.population-dot { fill: #fff; stroke: var(--gold); stroke-width: 7; }
.population-projection-zone { fill: rgba(76,201,240,.045); }

.population-scrubber { display: grid; gap: 12px; margin-top: 20px; }
.population-scrubber span,
.population-legend {
  color: var(--ink-3);
  font: 600 .68rem/1 var(--mono);
  letter-spacing: .1em;
  text-transform: uppercase;
}
.population-scrubber input { width: 100%; }
.population-legend { display: flex; flex-wrap: wrap; gap: 18px; margin-top: 22px; }
.population-legend span { display: inline-flex; align-items: center; gap: 8px; }
.population-legend i { width: 24px; height: 3px; background: var(--gold); }
.population-legend i.is-projection { background: repeating-linear-gradient(90deg, var(--cyan) 0 7px, transparent 7px 11px); }
.population-note { margin-top: 18px; color: var(--ink-3); font-size: .78rem; }

.history-source-links { display: flex; flex-wrap: wrap; gap: 8px 14px; margin-top: 12px; }
.history-source-links a { color: var(--cyan); }

@media (max-width: 900px) {
  .industrial-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .industrial-era:nth-child(2) { border-right: 0; }
  .industrial-era:nth-child(-n+2) { border-bottom: 1px solid var(--line); }
  .industrial-detail { grid-template-columns: 1fr; gap: 10px; }
}

@media (max-width: 620px) {
  nav { gap: 12px; }
  .history-back { font-size: .62rem; }
  .industrial-grid { grid-template-columns: 1fr; }
  .industrial-era,
  .industrial-era:nth-child(2) { border-right: 0; border-bottom: 1px solid var(--line); }
  .industrial-era:last-child { border-bottom: 0; }
  .population-readout { grid-template-columns: 1fr; }
  .population-readout > div,
  .population-readout > div:first-child {
    padding: 14px 0;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }
  .population-readout > div:last-child { border-bottom: 0; }
}

@media (prefers-reduced-motion: reduce) {
  .industrial-era { transition: none; }
}