/* Monochrome house rule — all illustrations use --md-default-fg-color
   for lines/text and --md-default-bg-color for fill/ground.
   Emphasis comes from weight, fill, and hatching. */

:root {
  --ill-fg: var(--md-default-fg-color, #000);
  --ill-bg: var(--md-default-bg-color, #fff);
}

/* Mermaid — inflate label padding so boxes breathe.
   Mermaid renders each label inside foreignObject > div.nodeLabel. */
.mermaid .node .label foreignObject {
  overflow: visible;
}
.mermaid .node .label foreignObject > div {
  padding: 8px 14px;
  line-height: 1.35;
}
.mermaid .cluster .label foreignObject > div {
  padding: 4px 10px;
}
.mermaid .node rect,
.mermaid .node polygon,
.mermaid .cluster rect {
  rx: 4;
  ry: 4;
}

/* Monochrome enforcement — overrides any stroke/fill Mermaid chose
   from its base-theme defaults (e.g., amber/yellow accents that
   leak through because not every theme variable maps cleanly). */
.mermaid svg .node rect,
.mermaid svg .node circle,
.mermaid svg .node ellipse,
.mermaid svg .node polygon,
.mermaid svg .node path,
.mermaid svg .cluster rect {
  stroke: var(--md-default-fg-color) !important;
  fill: var(--md-default-bg-color) !important;
}
.mermaid svg .edgePath .path,
.mermaid svg .flowchart-link,
.mermaid svg .arrowheadPath,
.mermaid svg marker path {
  stroke: var(--md-default-fg-color) !important;
  fill: var(--md-default-fg-color) !important;
}
.mermaid svg .edgeLabel,
.mermaid svg .edgeLabel rect,
.mermaid svg .edgeLabel foreignObject > div {
  background-color: var(--md-default-bg-color) !important;
  color: var(--md-default-fg-color) !important;
}
.mermaid svg .nodeLabel,
.mermaid svg .cluster-label {
  color: var(--md-default-fg-color) !important;
}

/* Routing-matrix illustration — Ch 8 */
.routing-matrix {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.85rem;
  margin: 1.5rem 0;
  table-layout: fixed;
  border: 1.5px solid var(--ill-fg);
}
.routing-matrix th,
.routing-matrix td {
  border: 1px solid var(--ill-fg);
  padding: 0.5rem 0.4rem;
  text-align: center;
  vertical-align: middle;
  line-height: 1.2;
  color: var(--ill-fg);
  background: var(--ill-bg);
}
.routing-matrix thead th {
  font-weight: 600;
  font-size: 0.75rem;
  border-bottom: 2px solid var(--ill-fg);
}
.routing-matrix td.row-label {
  text-align: left;
  font-weight: 500;
  font-size: 0.78rem;
  border-right: 2px solid var(--ill-fg);
}
.routing-matrix td.row-label small {
  display: block;
  font-weight: 400;
  opacity: 0.75;
  font-size: 0.7rem;
  margin-top: 2px;
}

/* Four cell types — all monochrome. Emphasis by fill/hatch, not colour. */

/* Fit — solid fill, bold label inverted */
.cell-fit {
  background: var(--ill-fg);
  color: var(--ill-bg);
  font-weight: 700;
}

/* Acceptable — 50% dot pattern (radial-gradient dots) on ground */
.cell-acceptable {
  background-image: radial-gradient(var(--ill-fg) 1px, transparent 1.2px);
  background-size: 6px 6px;
  background-position: 0 0;
  color: var(--ill-fg);
  font-weight: 500;
}

/* Poor — diagonal hatch, lighter density */
.cell-poor {
  background-image: repeating-linear-gradient(
    45deg,
    transparent 0,
    transparent 4px,
    var(--ill-fg) 4px,
    var(--ill-fg) 4.6px
  );
  color: var(--ill-fg);
  opacity: 0.85;
}

/* Do-not-route — empty cell with diagonal strike */
.cell-donot {
  background: var(--ill-bg);
  position: relative;
  color: transparent;
}
.cell-donot::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(
    to top right,
    transparent calc(50% - 1px),
    var(--ill-fg) calc(50% - 1px),
    var(--ill-fg) calc(50% + 1px),
    transparent calc(50% + 1px)
  );
}

/* Legend */
.matrix-legend {
  display: flex;
  gap: 1.5rem;
  flex-wrap: wrap;
  margin: 1rem 0;
  font-size: 0.85rem;
  color: var(--ill-fg);
}
.matrix-legend .swatch {
  display: inline-block;
  width: 1.2rem;
  height: 1.2rem;
  margin-right: 0.4rem;
  vertical-align: middle;
  border: 1px solid var(--ill-fg);
  background-color: var(--ill-bg);
}
.matrix-legend .swatch.cell-fit {
  background: var(--ill-fg);
}
.matrix-legend .swatch.cell-acceptable {
  background-image: radial-gradient(var(--ill-fg) 1px, transparent 1.2px);
  background-size: 6px 6px;
  background-color: var(--ill-bg);
}
.matrix-legend .swatch.cell-poor {
  background-image: repeating-linear-gradient(
    45deg,
    transparent 0,
    transparent 3px,
    var(--ill-fg) 3px,
    var(--ill-fg) 3.6px
  );
  background-color: var(--ill-bg);
}
.matrix-legend .swatch.cell-donot {
  background: linear-gradient(
    to top right,
    transparent calc(50% - 1px),
    var(--ill-fg) calc(50% - 1px),
    var(--ill-fg) calc(50% + 1px),
    transparent calc(50% + 1px)
  );
}

.matrix-footnote {
  font-size: 0.75rem;
  font-variant: small-caps;
  letter-spacing: 0.05em;
  opacity: 0.8;
  margin-top: 0.5rem;
  color: var(--ill-fg);
}