/* SPH Perception Demo — shared styles
 * Used by both sph-demo.html (standalone) and index.html (integrated).
 * All rules are scoped under .sph-card / .canvas-math-label / .stilde-label / .kernel-* so they
 * cannot leak into the host page. The standalone-only dark body background
 * lives inline in sph-demo.html, not here.
 */
.sph-demo-mount {
  position: relative;
}
.sph-demo-explainer {
  max-width: 900px;
  margin: 24px auto 0;
  color: #cbd3dc !important;
  font-size: 0.98rem;
  line-height: 1.65;
}
.sph-demo-explainer p {
  color: #cbd3dc !important;
}
.sph-card {
  --sph-bg: #111418;
  --sph-panel: #181c21;
  --sph-panel-soft: #14181d;
  --sph-canvas: #0b0e12;
  --sph-border: #2b333c;
  --sph-border-strong: #3a4652;
  --sph-text: #e8edf2;
  --sph-muted: #9aa6b2;
  --sph-subtle: #6f7d8a;
  --sph-accent: #66c28a;
  --sph-accent-strong: #3f9f68;
  --sph-accent-soft: rgba(102, 194, 138, 0.14);
  max-width: 960px;
  margin: 0 auto;
  background: var(--sph-bg);
  color: var(--sph-text) !important;
  border-radius: 14px;
  padding: 16px 20px 18px;
  display: grid;
  grid-template-columns: 200px minmax(0, 440px) 240px;
  grid-template-rows: auto 1fr;
  justify-content: center;
  column-gap: 16px;
  row-gap: 10px;
  box-shadow: 0 16px 42px rgba(0,0,0,0.58), inset 0 1px 0 rgba(255,255,255,0.04);
  font-family: 'Google Sans', system-ui, -apple-system, Segoe UI, Roboto, sans-serif;
}
.sph-card h2 {
  margin: 0 0 4px 0;
  font-size: 16px;
  font-weight: 600;
  color: var(--sph-text) !important;
  grid-column: 1 / -1;
  grid-row: 1;
}
.sph-card .perception-bar {
  grid-column: 1;
  grid-row: 2;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 4px;
}
.sph-card .perception-bar .label {
  font-weight: 600;
  font-size: 13px;
  color: var(--sph-muted) !important;
  margin-bottom: 2px;
}
.sph-card .perception-bar .chip-group {
  flex-direction: column;
  align-items: stretch;
  gap: 8px;
}
.sph-card .perception-bar .chip {
  text-align: left;
  padding: 8px 16px;
  font-size: 13px;
  white-space: nowrap;
}
.sph-card .kernels {
  grid-column: 1 / -1;
  grid-row: 4;
  display: flex;
  flex-direction: row;
  gap: 8px;
  margin-top: 4px;
}
.sph-card .kernel-block {
  background: var(--sph-canvas);
  border-radius: 8px;
  border: 1px solid var(--sph-border);
  flex: 1 1 0;
  min-width: 0;
  overflow: hidden;
}
.sph-card .kernel-plot {
  /* Bottom padding holds the |r| label; the epsilon tick is positioned by JS. */
  padding: 4px 4px 20px 4px;
  position: relative;
}
.sph-card .kernel-y-label {
  position: absolute;
  top: 6px;
  left: 22px;
  color: var(--sph-text) !important;
  pointer-events: none;
  z-index: 2;
}
.sph-card .kernel-x-label {
  position: absolute;
  bottom: 12px;
  left: 50%;
  transform: translateX(-50%);
  color: var(--sph-text) !important;
  pointer-events: none;
  z-index: 2;
}
.sph-card .kernel-eps-label {
  /* Both `top` and `left` are set dynamically each frame in drawKernelOnto
     so the label always sits just under the dashed ε guide line on the axis. */
  position: absolute;
  transform: translate(-50%, 0);
  color: var(--sph-muted) !important;
  pointer-events: none;
  z-index: 2;
}
.sph-card .kernel-y-label mjx-container,
.sph-card .kernel-x-label mjx-container,
.sph-card .kernel-eps-label mjx-container { font-size: 1em; }
.sph-card .kernel-block .kt {
  font-size: 11px;
  color: var(--sph-muted) !important;
  padding: 2px 4px;
}
.sph-card .kernel-block canvas {
  display: block;
  width: 100%;
  height: 150px;
}
.sph-card .kernel-formula {
  border-top: 1px solid var(--sph-border);
  padding: 8px 8px 10px;
  color: var(--sph-text) !important;
  overflow-x: auto;
  min-height: 54px;
}
.sph-card .kernel-formula mjx-container {
  font-size: 0.78em;
  margin: 0 !important;
}
.sph-card .main {
  grid-column: 2;
  grid-row: 2;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  min-width: 0;
}
.sph-card .main canvas#main-canvas {
  width: 100%;
  max-width: 440px;
  aspect-ratio: 1;
  background: var(--sph-canvas);
  border-radius: 10px;
  border: 1px solid var(--sph-border);
  cursor: grab;
  touch-action: none;
  display: block;
  align-self: center;
}
.sph-card .main canvas#main-canvas.dragging { cursor: grabbing; }
.sph-card .controls-col {
  grid-column: 3;
  grid-row: 2;
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 13px;
}
.sph-card details {
  background: var(--sph-panel);
  border: 1px solid var(--sph-border);
  border-radius: 8px;
  padding: 6px 10px 8px;
}
.sph-card details > summary {
  cursor: pointer;
  font-weight: 600;
  list-style: none;
  padding: 2px 0;
  color: var(--sph-text) !important;
  user-select: none;
}
.sph-card details > summary::-webkit-details-marker { display: none; }
.sph-card details > summary::before {
  content: "▸";
  display: inline-block;
  width: 14px;
  color: var(--sph-subtle) !important;
  transition: transform 0.15s;
}
.sph-card details[open] > summary::before { content: "▾"; }
.sph-card .folder-body {
  padding-top: 6px;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.sph-card .slider-row {
  display: grid;
  grid-template-columns: 24px 1fr 42px;
  align-items: center;
  gap: 6px;
}
.sph-card .slider-row .nm {
  font-style: italic;
  color: var(--sph-text) !important;
}
.sph-card .slider-row .vl {
  font-variant-numeric: tabular-nums;
  color: var(--sph-muted) !important;
  font-size: 12px;
  text-align: right;
}
.sph-card input[type=range] {
  accent-color: var(--sph-accent);
  width: 100%;
  margin: 0;
}
.sph-card .group-label {
  font-size: 12px;
  color: var(--sph-muted) !important;
  margin-top: 2px;
}
.sph-card .chip-group {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
}
.sph-card .chip {
  display: inline-block;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--sph-border-strong);
  background: #101419;
  cursor: pointer;
  font-size: 12px;
  color: var(--sph-text) !important;
  user-select: none;
  font-family: inherit;
  transition: background 0.1s, border-color 0.1s, color 0.1s;
}
.sph-card .chip:hover {
  background: var(--sph-accent-soft);
  border-color: var(--sph-accent);
}
.sph-card .chip.active {
  background: var(--sph-accent-strong);
  color: #fff !important;
  border-color: var(--sph-accent);
}
.sph-card .btn {
  background: #101419;
  border: 1px solid var(--sph-border-strong);
  border-radius: 6px;
  padding: 5px 10px;
  cursor: pointer;
  font-family: inherit;
  font-size: 12px;
  color: var(--sph-text) !important;
}
.sph-card .btn:hover {
  background: var(--sph-accent-soft);
  border-color: var(--sph-accent);
}
.sph-card .btn.primary {
  background: var(--sph-accent-strong);
  color: #fff !important;
  border-color: var(--sph-accent);
  font-weight: 600;
  padding: 7px 12px;
  margin-top: 4px;
}
.sph-card .btn.primary:hover { background: #34875a; }
.sph-card .zoom-readout {
  font-size: 12px;
  color: var(--sph-muted) !important;
  font-variant-numeric: tabular-nums;
}
.sph-card .hint {
  font-size: 11px;
  color: var(--sph-subtle) !important;
  line-height: 1.4;
  padding: 4px 2px 0;
  text-align: center;
}
.sph-card .formula-display {
  grid-column: 1 / -1;
  grid-row: 3;
  text-align: center;
  min-height: 36px;
  padding: 8px 4px 0;
  color: var(--sph-text) !important;
  overflow-x: auto;
}
.sph-card .formula-display mjx-container { font-size: 1.1em; }
.sph-card .chip-math { margin-right: 5px; }
.sph-card .chip-math mjx-container { font-size: 1em; }

/* Canvas annotations rendered as HTML overlays so MathJax can draw the glyphs. */
.canvas-math-label,
.stilde-label {
  position: absolute;
  pointer-events: none;
  color: #e8edf2 !important;
  line-height: 1;
  display: none;
  user-select: none;
  z-index: 100;
  text-shadow: 0 0 4px #0b0e12, 0 0 4px #0b0e12, 0 0 8px #0b0e12;
}
.canvas-math-label {
  transform: translate(0, -50%);
}
.stilde-label {
  transform: translate(-50%, -100%);
}
.canvas-math-label mjx-container {
  color: #e8edf2 !important;
  font-size: 1.3em !important;
}
.stilde-label mjx-container {
  color: #e8edf2 !important;
  font-size: 1.25em !important;
}

/* Narrow layout */
@media (max-width: 900px) {
  .sph-card {
    grid-template-columns: 1fr;
  }
  .sph-card .perception-bar { grid-column: 1; grid-row: auto; }
  .sph-card .perception-bar .chip-group { flex-direction: row; flex-wrap: wrap; }
  .sph-card .perception-bar .chip { text-align: center; }
  .sph-card .main { grid-column: 1; grid-row: auto; }
  .sph-card .controls-col { grid-column: 1; grid-row: auto; }
}