/* Reaction–diffusion lab — Gray–Scott on a torus.
   Class names are .rd-* prefixed to namespace this artifact. */

.rd {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 280px;
  gap: 2.5rem;
  align-items: start;
  margin: 0 0 2rem;
}

.rd-board {
  min-width: 0;
  aspect-ratio: 1 / 1;
  border: 1px solid var(--rule);
  background: var(--bg-deep);
  position: relative;
}
.rd-board canvas {
  display: block;
  width: 100%;
  height: 100%;
  /* The simulation buffer is only 200×200; let the browser nearest-neighbor
     scale it to fill the container without smoothing the chemistry away. */
  image-rendering: pixelated;
  image-rendering: -moz-crisp-edges;
  /* Stop touch-drag from scrolling the page while painting. */
  touch-action: none;
  cursor: crosshair;
}

/* phase map column */
.rd-side {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
  align-self: stretch;
}
.rd-phase-map {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}
.rd-phase-map .ctrl-label {
  font-family: var(--mono);
  font-size: 0.74rem;
  color: var(--muted);
  text-transform: lowercase;
  letter-spacing: 0.06em;
}
.rd-phase-map canvas {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 280 / 180;
  border: 1px solid var(--rule);
  background: transparent;
}
.rd-phase-hint {
  font-family: var(--serif);
  font-style: italic;
  font-size: 0.88rem;
  color: var(--muted);
  margin: 0;
  line-height: 1.4;
}
.rd-phase-hint em {
  font-family: var(--mono);
  font-style: normal;
  font-size: 0.85em;
  padding: 0.05em 0.35em;
  border: 1px solid var(--rule);
  border-radius: 4px;
  color: var(--ink);
}

@media (max-width: 820px) {
  .rd {
    grid-template-columns: 1fr;
    gap: 1.75rem;
  }
}

/* shared control conventions (mirrors collisions) */

.rd-controls {
  display: flex;
  flex-direction: column;
  gap: 1rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--rule);
}
.ctrl-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
  align-items: center;
}
.ctrl-row.sliders {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(170px, 1fr));
  gap: 1.5rem;
}
.row-control {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}
.row-control .label-row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  font-family: var(--mono);
  font-size: 0.72rem;
  color: var(--muted);
  text-transform: lowercase;
  letter-spacing: 0.04em;
}
.row-control .value {
  color: var(--ink-soft);
  font-feature-settings: "tnum" 1;
  text-transform: none;
}

input[type="range"] {
  -webkit-appearance: none;
  appearance: none;
  width: 100%;
  height: 14px;
  background: transparent;
  cursor: pointer;
  margin: 0;
}
input[type="range"]::-webkit-slider-runnable-track {
  height: 1px;
  background: var(--rule);
}
input[type="range"]::-moz-range-track {
  height: 1px;
  background: var(--rule);
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent-warm);
  margin-top: -6px;
  border: none;
  transition: transform 0.15s ease;
}
input[type="range"]::-moz-range-thumb {
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--accent-warm);
  border: none;
}
input[type="range"]:hover::-webkit-slider-thumb {
  transform: scale(1.25);
}
@media (prefers-reduced-motion: reduce) {
  input[type="range"]::-webkit-slider-thumb {
    transition: none;
  }
}

.rd-controls button {
  font-family: var(--mono);
  font-size: 0.78rem;
  padding: 0.4rem 0.95rem;
  background: transparent;
  border: 1px solid var(--rule);
  color: var(--ink-soft);
  border-radius: 999px;
  cursor: pointer;
  letter-spacing: 0.04em;
  text-transform: lowercase;
  transition: color 0.2s, border-color 0.2s, background 0.2s;
}
.rd-controls button:hover {
  color: var(--accent-warm);
  border-color: var(--accent-warm);
}
.rd-controls button.is-active {
  color: var(--accent-warm);
  border-color: var(--accent-warm);
  background: color-mix(in srgb, var(--accent-warm) 8%, transparent);
}

/* presets row: leading label, then chips */
.rd-presets {
  align-items: center;
  gap: 0.6rem;
}
.rd-presets .ctrl-label {
  font-family: var(--mono);
  font-size: 0.74rem;
  color: var(--muted);
  text-transform: lowercase;
  letter-spacing: 0.06em;
  margin-right: 0.25rem;
}

/* notes-shared em boxes */
.notes em {
  font-family: var(--mono);
  font-style: normal;
  font-size: 0.85em;
  padding: 0.05em 0.4em;
  border: 1px solid var(--rule);
  border-radius: 4px;
  color: var(--ink);
  margin: 0 0.1em;
}