/* MV vs PC-WMV section: PC-WMV beats Standard MV at the per-problem level.
   gpt-oss-20b on AIME 2025 #14 (gold=60). N=16 samples, tau=0.75, K=1. */

.mvpc-section {
  padding: 2rem 1.25rem 2.5rem;
  background: white;
}
.mvpc-problem {
  max-width: 880px;
  margin: 0 auto 1.4rem;
  padding: 1rem 1.2rem;
  background: #fbfcfe;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  box-shadow: 0 1px 2px rgba(15, 23, 42, 0.04);
}
.mvpc-problem .problem-meta {
  font-size: 0.78rem;
  color: #64748b;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-weight: 600;
  margin-bottom: 0.45rem;
}
.mvpc-problem .problem-meta .gold-pill {
  display: inline-block;
  margin-left: 0.6rem;
  padding: 0.05rem 0.55rem;
  background: #ecfdf5;
  color: #047857;
  border-radius: 999px;
  letter-spacing: 0.04em;
  font-size: 0.74rem;
  text-transform: none;
}
.mvpc-problem .problem-text {
  font-size: 0.94rem;
  line-height: 1.55;
  color: #0f172a;
}
.mvpc-problem .nb { white-space: nowrap; }

/* Sample stream: 16 dots */
.mvpc-stream {
  max-width: 880px;
  margin: 0 auto 1rem;
}
.mvpc-stream-label {
  font-size: 0.78rem;
  color: #64748b;
  font-weight: 600;
  margin-bottom: 0.5rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}
.mvpc-dots {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  align-items: center;
}
.mvpc-dot {
  width: 1.5rem;
  height: 1.5rem;
  border-radius: 50%;
  background: var(--dot-color, #94a3b8);
  opacity: 0;
  transform: scale(0.5);
  transition: opacity 0.3s ease, transform 0.3s ease, filter 0.3s ease;
  position: relative;
  /* not-self-consistent: more transparent (washed out) */
  --dot-fade: 0.4;
}
.mvpc-dot.consistent {
  --dot-fade: 1.0;
  box-shadow: 0 0 0 2px white, 0 0 0 3.5px var(--dot-color);
}
.mvpc-dot.lit {
  opacity: var(--dot-fade);
  transform: scale(1);
}
.mvpc-dot.consistent.lit {
  opacity: 1;
}

/* Cost-equivalence extras for Standard MV: smaller, no possible ring. They
   stay hidden (opacity 0 from .mvpc-dot) until lit, just like regular dots. */
.mvpc-dot.mv-only {
  width: 1.05rem;
  height: 1.05rem;
}
.mvpc-dot.mv-only.lit { opacity: 0.65; }

/* Visual divider between regular samples and the cost-equivalence extras.
   Hidden until the animation reaches the first mv_only sample, at which
   point JS adds .revealed to fade it (and its label) in. */
.mvpc-dot-divider {
  display: inline-flex;
  align-items: center;
  margin: 0 0.4rem 0 0.2rem;
  height: 1.5rem;
  border-left: 1.5px dashed #cbd5e1;
  padding-left: 0.5rem;
  position: relative;
  opacity: 0;
  transform: scaleY(0.55);
  transform-origin: center;
  transition: opacity 0.45s ease, transform 0.45s ease;
}
.mvpc-dot-divider.revealed {
  opacity: 1;
  transform: scaleY(1);
}
.mvpc-dot-divider .divider-label {
  font-size: 0.7rem;
  color: #64748b;
  font-style: italic;
  font-weight: 600;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

/* Currently-processing dot: scale up + circular drop-shadow halo. We use
   filter:drop-shadow (which follows the dot's circular shape) instead of
   box-shadow so the halo never reads as a ring -- the ring shape is
   reserved for self-consistent dots (see .mvpc-dot.consistent). */
.mvpc-dot.active-step {
  transform: scale(1.32);
  filter: drop-shadow(0 0 6px var(--dot-color));
  z-index: 1;
}
.mvpc-dot[data-tooltip]:hover::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: calc(100% + 6px);
  left: 50%;
  transform: translateX(-50%);
  background: #0f172a;
  color: white;
  padding: 0.3rem 0.55rem;
  border-radius: 6px;
  font-size: 0.72rem;
  font-family: ui-monospace, "SF Mono", "JetBrains Mono", monospace;
  white-space: nowrap;
  z-index: 10;
  pointer-events: none;
}

.mvpc-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 0.9rem;
  margin-top: 0.75rem;
  font-size: 0.78rem;
  color: #475569;
}
.mvpc-legend-item {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
}
.mvpc-legend-swatch {
  display: inline-block;
  width: 0.7rem;
  height: 0.7rem;
  border-radius: 50%;
}
/* Ringed swatch in the legend. Mirrors .mvpc-dot.consistent so the
   reader can match the legend symbol to the actual ringed dots above. */
.mvpc-legend-swatch.ring {
  background: #64748b;
  box-shadow: 0 0 0 1.2px white, 0 0 0 2.2px #64748b;
}
.mvpc-legend-hint {
  margin-left: 0.4rem;
  padding-left: 0.9rem;
  border-left: 1px solid #cbd5e1;
  color: #475569;
}
.mvpc-legend-hint .hint-paren {
  color: #94a3b8;
}

/* Per-step stepper card */
.mvpc-stepper {
  max-width: 880px;
  margin: 1.4rem auto 0;
  padding: 0.85rem 1rem 0.95rem;
  background: white;
  border: 1px solid #e2e8f0;
  border-radius: 10px;
  box-shadow: 0 2px 8px rgba(15, 23, 42, 0.04);
  min-height: 4rem;
  opacity: 0.55;
  transition: opacity 0.3s ease;
}
.mvpc-stepper.active { opacity: 1; }

.mvpc-stepper .step-counter {
  font-size: 0.78rem;
  color: #64748b;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 700;
  margin-bottom: 0.45rem;
  font-feature-settings: "tnum" 1;
  min-height: 0.9em;
}
.mvpc-stepper .step-pair {
  font-size: 0.95rem;
  color: #0f172a;
  margin-bottom: 0.45rem;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 0.55rem;
  min-height: 1.4rem;
}
.mvpc-stepper .step-side {
  font-feature-settings: "tnum" 1;
}
.mvpc-stepper .step-arrow {
  color: #cbd5e1;
  font-weight: 700;
}
.mvpc-stepper .step-tag {
  font-size: 0.74rem;
  font-weight: 600;
  padding: 0.1rem 0.5rem;
  border-radius: 999px;
  letter-spacing: 0.02em;
}
.mvpc-stepper .step-tag-eq {
  background: #ecfdf5;
  color: #047857;
}
.mvpc-stepper .step-tag-neq {
  background: #f1f5f9;
  color: #64748b;
}
/* Inline answer chip used inside the stepper. Inherits color from class
   via the --chip-color custom property. */
.step-chip {
  display: inline-block;
  padding: 0.05em 0.45em;
  border-radius: 4px;
  background: color-mix(in srgb, var(--chip-color) 12%, white);
  color: var(--chip-color);
  border: 1px solid color-mix(in srgb, var(--chip-color) 35%, white);
  font-weight: 700;
  font-feature-settings: "tnum" 1;
  margin: 0 0.05em;
}
@supports not (background: color-mix(in srgb, red 50%, white)) {
  /* Fallback for browsers without color-mix: solid soft fill */
  .step-chip {
    background: #f8fafc;
    border-color: var(--chip-color);
  }
}

/* Two voting panels */
.mvpc-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.1rem;
  max-width: 1100px;
  margin: 1.6rem auto 0;
}
@media (max-width: 880px) {
  .mvpc-grid { grid-template-columns: 1fr; }
}

.vote-panel {
  background: #fbfcfe;
  border: 1px solid #e2e8f0;
  border-radius: 12px;
  padding: 1rem 1.1rem 1.15rem;
  position: relative;
}
.vote-panel.mv     { border-color: #fecaca; }
.vote-panel.pcwmv  { border-color: #bbf7d0; }
.vote-panel-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  border-bottom: 1px solid #f1f5f9;
  padding-bottom: 0.5rem;
  margin-bottom: 0.65rem;
}
.vote-panel-title {
  font-weight: 700;
  font-size: 1rem;
  letter-spacing: -0.01em;
}
.vote-panel.mv    .vote-panel-title { color: #b91c1c; }
.vote-panel.pcwmv .vote-panel-title { color: #047857; }
.vote-panel-rule {
  font-size: 0.74rem;
  color: #64748b;
  font-weight: 600;
}

.vote-rows {
  display: flex;
  flex-direction: column;
  gap: 0.45rem;
}
.vote-row {
  display: grid;
  grid-template-columns: 4.5rem 1fr 4rem;
  align-items: center;
  gap: 0.55rem;
  font-size: 0.86rem;
}
.vote-row .vote-key {
  font-weight: 700;
  font-feature-settings: "tnum" 1;
  color: var(--row-color, #1e293b);
  letter-spacing: -0.01em;
  text-align: right;
  padding-right: 0.2rem;
}

.vote-bar-track {
  height: 14px;
  background: #f1f5f9;
  border-radius: 7px;
  overflow: hidden;
  position: relative;
}
.vote-bar-fill {
  display: block;
  height: 100%;
  width: 0%;
  border-radius: 7px;
  background: var(--row-color, #94a3b8);
  /* width is driven per-frame from JS */
}
.vote-row .vote-val {
  font-feature-settings: "tnum" 1;
  font-weight: 600;
  color: #334155;
  font-size: 0.85rem;
  text-align: left;
}

/* When a row receives a vote/weight in the current step, briefly highlight it
   in the answer's own color. The row exposes --row-color which doubles as
   the bar fill color, so the pulse and the bar always agree. */
.vote-row.flashing {
  animation: mvpc-row-pulse 0.85s ease-out;
}
@keyframes mvpc-row-pulse {
  0%   { box-shadow: 0 0 0 0 var(--row-color); }
  20%  { box-shadow: 0 0 0 5px color-mix(in srgb, var(--row-color) 22%, transparent); }
  100% { box-shadow: 0 0 0 0 var(--row-color); }
}
@supports not (background: color-mix(in srgb, red 50%, white)) {
  @keyframes mvpc-row-pulse {
    0%   { box-shadow: 0 0 0 0 var(--row-color); }
    20%  { box-shadow: 0 0 0 5px var(--row-color); }
    100% { box-shadow: 0 0 0 0 var(--row-color); }
  }
}

.vote-residual {
  margin-top: 0.55rem;
  font-size: 0.78rem;
  color: #64748b;
  font-style: italic;
  padding-left: 0.2rem;
  opacity: 0;
  transform: translateY(3px);
  transition: opacity 0.4s ease, transform 0.4s ease;
}
.vote-residual.shown {
  opacity: 1;
  transform: translateY(0);
}

.vote-pick {
  margin-top: 0.85rem;
  padding-top: 0.65rem;
  border-top: 1px dashed #e2e8f0;
  font-size: 0.92rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  opacity: 0;
  transform: translateY(4px);
  transition: opacity 0.4s ease, transform 0.4s ease;
}
.vote-pick.shown { opacity: 1; transform: translateY(0); }
.vote-panel.mv    .vote-pick { color: #b91c1c; }
.vote-panel.pcwmv .vote-pick { color: #047857; }
.vote-pick .pick-symbol {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 1.4rem;
  height: 1.4rem;
  border-radius: 50%;
  font-size: 0.85rem;
  font-weight: 800;
  color: white;
}
.vote-panel.mv    .vote-pick .pick-symbol { background: #b91c1c; }
.vote-panel.pcwmv .vote-pick .pick-symbol { background: #047857; }
.vote-pick .pick-tied {
  font-size: 0.78rem;
  font-weight: 500;
  color: #64748b;
  margin-left: 0.35rem;
}

.mvpc-controls {
  margin-top: 1.4rem;
  display: flex;
  justify-content: center;
  gap: 0.7rem;
}
.mvpc-replay {
  appearance: none;
  background: #0f172a;
  color: white;
  border: 0;
  padding: 0.5rem 1rem;
  border-radius: 999px;
  font-size: 0.85rem;
  font-weight: 600;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
}
.mvpc-replay:hover { background: #1e293b; }
.mvpc-replay svg { width: 0.9rem; height: 0.9rem; }

.mvpc-footer {
  text-align: center;
  font-size: 0.78rem;
  color: #64748b;
  margin-top: 1rem;
}
.mvpc-footer code {
  background: #f1f5f9;
  padding: 0.05em 0.35em;
  border-radius: 3px;
}

/* Flying delta badge: spawned at the orig/regen chip in the stepper,
   animates to the corresponding row in the voting panel. The badge takes
   the answer's color via --flyer-color, set inline by JS. */
.vote-flyer {
  position: fixed;
  font-size: 0.92rem;
  font-weight: 700;
  font-feature-settings: "tnum" 1;
  padding: 0.2rem 0.55rem;
  border-radius: 8px;
  pointer-events: none;
  white-space: nowrap;
  z-index: 1000;
  box-shadow: 0 4px 14px rgba(15, 23, 42, 0.18);
  will-change: transform, opacity;
  background: color-mix(in srgb, var(--flyer-color) 14%, white);
  color: var(--flyer-color);
  border: 1.5px solid color-mix(in srgb, var(--flyer-color) 45%, white);
}
@supports not (background: color-mix(in srgb, red 50%, white)) {
  .vote-flyer {
    background: white;
    color: var(--flyer-color);
    border: 1.5px solid var(--flyer-color);
  }
}

/* Reduced motion: instant end state */
@media (prefers-reduced-motion: reduce) {
  .mvpc-dot,
  .vote-pick {
    opacity: 1 !important;
    transform: none !important;
  }
}