/* ===========================================================
   Section 4 — demand-side spending + cost-per-beneficiary slider
   =========================================================== */

.s4-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.4fr) minmax(360px, 1fr);
  gap: 2rem;
  max-width: var(--max-w-wide);
  margin: 0 auto;
  padding: 0 1.5rem;
  align-items: stretch;
}

.s4-chart-frame .chart {
  height: clamp(440px, 56vh, 640px);
}

/* ----- slider panel ----- */
.s4-slider-frame {
  display: flex;
  flex-direction: column;
  gap: 1.4rem;
  padding: 1.6rem 1.6rem 1.4rem;
}

.s4-slider-block {}

.s4-cost-display {
  text-align: center;
  font-family: var(--serif);
  font-style: italic;
  margin-bottom: 1.2rem;
}
.s4-cost-display .s4-prefix,
.s4-cost-display .s4-suffix {
  color: var(--ink-soft);
  font-size: 1rem;
  margin: 0 0.3rem;
}
.s4-cost-display #s4-cost-value {
  font-size: clamp(2.6rem, 5vw, 4.2rem);
  font-weight: 700;
  color: var(--gold);
  text-shadow: 0 0 24px var(--gold-glow);
  font-variant-numeric: tabular-nums;
  letter-spacing: -0.02em;
  font-family: var(--serif);
}

/* range styling */
#s4-cost-slider {
  appearance: none;
  -webkit-appearance: none;
  width: 100%;
  height: 8px;
  background: linear-gradient(90deg, var(--green), var(--cool), var(--gold), var(--crisis));
  border-radius: 999px;
  outline: none;
  cursor: pointer;
  box-shadow: 0 0 24px rgba(255, 255, 255, 0.06), inset 0 0 4px rgba(0, 0, 0, 0.4);
}
#s4-cost-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #ffffff;
  border: 3px solid var(--gold);
  cursor: grab;
  box-shadow: 0 0 16px var(--gold-glow), 0 4px 12px rgba(0,0,0,0.5);
  transition: transform 0.12s ease;
}
#s4-cost-slider::-webkit-slider-thumb:active { cursor: grabbing; transform: scale(1.15); }
#s4-cost-slider::-moz-range-thumb {
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #ffffff;
  border: 3px solid var(--gold);
  cursor: grab;
  box-shadow: 0 0 16px var(--gold-glow);
}

.s4-slider-marks {
  display: flex;
  justify-content: space-between;
  margin-top: 0.6rem;
  font-family: var(--mono);
  font-size: 0.66rem;
  letter-spacing: 0.08em;
  color: var(--ink-mute);
}

/* ----- derive block (the math output) ----- */
.s4-derive-block {
  background: rgba(8, 14, 28, 0.5);
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 12px;
  padding: 1rem 1.2rem;
}
.s4-derive-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  padding: 0.5rem 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}
.s4-derive-row:last-child { border-bottom: none; }
.s4-derive-label {
  font-family: var(--mono);
  font-size: 0.74rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--ink-mute);
}
.s4-derive-val {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-weight: 600;
  color: var(--ink);
  text-align: right;
}
.s4-derive-row.s4-derive-result .s4-derive-label {
  color: var(--ink);
  text-shadow: 0 0 8px rgba(255, 23, 68, 0.4);
}
.s4-big {
  font-size: clamp(1.6rem, 3vw, 2.4rem);
  color: var(--crisis) !important;
  text-shadow: 0 0 14px var(--crisis-glow);
  font-family: var(--serif) !important;
  font-style: italic;
  font-weight: 700 !important;
}

.s4-note {
  font-family: var(--serif);
  font-style: italic;
  font-size: 0.92rem;
  color: var(--ink-soft);
  line-height: 1.55;
  margin-top: 0.4rem;
  opacity: 0.85;
}

/* ----- narrative columns below ----- */
.s4-narrative {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  max-width: var(--max-w-wide);
  margin: 4rem auto 0;
  padding: 0 1.5rem;
}
.s4-narrative-col p {
  color: var(--ink);
  opacity: 0.92;
  font-size: 1.08rem;
  line-height: 1.7;
  margin: 0 0 0.9rem;
}

@media (max-width: 1100px) {
  .s4-grid {
    grid-template-columns: 1fr;
  }
  .s4-narrative {
    grid-template-columns: 1fr;
    gap: 1.5rem;
  }
}