/* Article typography. Scope: any element with class "prose", or body.prose.
   Body copy is Literata; headings, tables, tags, callout labels and other UI text are Nunito Sans. */

html {
  /* 17px base: every rem-based size reads a notch larger, and still follows the browser setting. */
  font-size: 106.25%;
}

.prose {
  font-family: var(--font-prose);
  font-size: var(--text-base);
  line-height: var(--leading-body);
  color: var(--fg);
  background: var(--bg);
  overflow-wrap: break-word;
  -webkit-font-smoothing: antialiased;
}

.prose *,
.prose *::before,
.prose *::after {
  box-sizing: border-box;
}

.prose h1,
.prose h2,
.prose h3,
.prose h4 {
  font-family: var(--font-ui);
  line-height: var(--leading-heading);
  font-weight: 800;
  letter-spacing: -0.01em;
  margin: 1.8em 0 0.6em;
  text-wrap: balance;
}

.prose h1 { font-size: var(--text-h1); margin-top: 0; }
.prose h2 { font-size: var(--text-h2); }
.prose h3 { font-size: var(--text-h3); }
.prose h4 { font-size: var(--text-h4); }

.prose p,
.prose ul,
.prose ol,
.prose dl,
.prose blockquote,
.prose pre,
.prose figure,
.prose details {
  margin: 0 0 1em;
}

/* Lists: bullets are small muted dots; ordered lists keep numbers with muted markers. */
.prose ul,
.prose ol {
  padding-left: 1.5em;
}

.prose ul {
  list-style: none;
}

.prose ul > li {
  position: relative;
}

.prose ul > li::before {
  content: "";
  position: absolute;
  left: -1.05em;
  top: 0.72em;
  width: 0.36em;
  height: 0.36em;
  border-radius: 50%;
  background: color-mix(in srgb, var(--muted) 75%, transparent);
}

.prose ol > li::marker {
  color: var(--muted);
  font-weight: 600;
}

.prose li {
  margin: 0.3em 0;
}

.prose li > ul,
.prose li > ol {
  margin-bottom: 0;
}

.prose strong {
  font-weight: 600;
}

/* Links */
.prose a {
  color: var(--accent);
  font-weight: 600;
  text-decoration: underline;
  text-decoration-color: color-mix(in srgb, var(--accent) 35%, transparent);
  text-underline-offset: 3px;
}

.prose a:hover {
  text-decoration-color: var(--accent);
}

.prose :focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 0.5rem;
}

.prose blockquote {
  padding: 0.25em 1em;
  border-left: 3px solid var(--border);
  color: var(--muted);
  font-style: italic;
}

.prose blockquote > :last-child {
  margin-bottom: 0;
}

.prose hr {
  border: 0;
  border-top: 1px solid var(--border);
  margin: 2em 0;
}

/* Code */
.prose code,
.prose kbd,
.prose samp {
  font-family: var(--font-mono);
  font-size: var(--text-code);
}

.prose :not(pre) > code {
  background: var(--subtle);
  padding: 0.12em 0.4em;
  border-radius: var(--radius-code);
}

.prose pre {
  background: var(--subtle);
  border-radius: var(--radius);
  padding: var(--space-4);
  overflow-x: auto;
  white-space: pre;
  line-height: 1.5;
  tab-size: 2;
}

.prose pre code {
  font-size: 0.88em;
  background: none;
  padding: 0;
}

.kbd,
.prose kbd {
  font-family: var(--font-mono);
  font-size: 0.85em;
  padding: 0.1em 0.45em;
  border: 1px solid var(--border);
  border-bottom-width: 2px;
  border-radius: var(--radius-code);
  background: var(--surface);
  color: var(--fg);
  white-space: nowrap;
}

/* Tables: a card-like container that scrolls sideways instead of crushing the columns. */
.table-wrap {
  overflow-x: auto;
  margin: 0 0 1.25em;
  max-width: 100%;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-panel);
}

.prose table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-ui);
  font-size: var(--text-sm);
  line-height: 1.45;
}

.prose :not(.table-wrap) > table {
  margin: 0 0 1.25em;
}

.prose th,
.prose td {
  padding: 0.7em 1em;
  text-align: left;
  vertical-align: top;
  border-bottom: 1px solid var(--border);
}

.prose thead th {
  background: var(--subtle);
  font-weight: 700;
}

.prose tbody tr:last-child td {
  border-bottom: 0;
}

/* Narrow screens: wide tables (marked .wide, or with 3+ columns) keep a readable width and scroll.
   Browsers without :has() support skip the second rule and rely on .wide alone. */
@media (max-width: 599px) {
  .table-wrap.wide table {
    min-width: 36rem;
  }

  .table-wrap:has(th:nth-child(3)) table {
    min-width: 36rem;
  }
}

.table-wrap--sticky {
  max-height: 70vh;
}

.table-wrap--sticky thead th {
  position: sticky;
  top: 0;
  z-index: 1;
}

/* Figures */
.prose figure {
  text-align: center;
}

.prose figure img,
.prose figure svg {
  max-width: 100%;
  height: auto;
}

.prose figcaption {
  font-family: var(--font-ui);
  font-size: var(--text-xs);
  color: var(--muted);
  margin-top: 0.5em;
}

.prose img {
  max-width: 100%;
  height: auto;
}

/* KaTeX: display maths has no box; it stays centred and scrolls sideways when too wide. */
.prose .katex-display {
  overflow-x: auto;
  overflow-y: hidden;
  padding: 0.25em 0;
  /* Block margins only: the shell centres blocks with auto inline margins. */
  margin-top: 1em;
  margin-bottom: 1em;
}

/* KaTeX's hidden MathML copy is position: absolute. Anchor it to its formula so that, inside a
   sideways-scrolling table or display block, it cannot widen the page at phone width. */
.prose .katex {
  position: relative;
}

/* Callouts: a plain card. Variants differ only by the 3px left rule and the label colour. */
.callout {
  --callout-accent: var(--muted);
  background: var(--surface);
  border: 1px solid var(--border);
  border-left: 3px solid var(--callout-accent);
  border-radius: var(--radius-panel);
  padding: var(--space-3) var(--space-4);
  margin: 0 0 1.25em;
}

.callout > :last-child {
  margin-bottom: 0;
}

.callout > :first-child {
  margin-top: 0;
}

.callout__title,
.callout > strong:first-child {
  display: block;
  font-family: var(--font-ui);
  font-size: 0.8rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: var(--callout-accent);
  margin-bottom: 0.35em;
}

.callout--note { --callout-accent: var(--muted); }
.callout--say { --callout-accent: var(--accent); }
.callout--warn { --callout-accent: var(--warn); }
.callout--inference { --callout-accent: var(--muted); border-left-style: dashed; }

/* Tags: a plain pill; the status shows as a tiny leading dot.
   Inline (not inline-block) so trailing punctuation cannot wrap away from the tag. */
.tag {
  display: inline;
  font-family: var(--font-ui);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  line-height: 1;
  padding: 0.3em 0.7em;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: var(--subtle);
  color: var(--muted);
  vertical-align: 0.1em;
  white-space: nowrap;
}

.tag--confirmed::before,
.tag--reported::before,
.tag--inference::before {
  content: "";
  display: inline-block;
  width: 0.5em;
  height: 0.5em;
  margin-right: 0.5em;
  border-radius: 50%;
  vertical-align: 0.05em;
}

.tag--confirmed::before { background: var(--accent); }
.tag--reported::before { background: var(--muted); }
.tag--inference::before { border: 1px dashed var(--muted); }

/* Columns */
.cols-2 {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--space-5);
  margin: 0 0 1.25em;
}

.cols-2 > * {
  min-width: 0;
}

@media (max-width: 700px) {
  .cols-2 {
    grid-template-columns: minmax(0, 1fr);
    gap: var(--space-3);
  }
}

/* Details: a surface card with a chevron on the summary. */
.prose details {
  border: 1px solid var(--border);
  border-radius: var(--radius-panel);
  padding: 0 1em;
  background: var(--surface);
}

.prose summary {
  display: flex;
  align-items: center;
  gap: 0.6em;
  min-height: var(--tap);
  cursor: pointer;
  list-style: none;
  font-family: var(--font-ui);
  font-weight: 700;
  font-size: var(--text-sm);
}

.prose summary::-webkit-details-marker {
  display: none;
}

.prose summary::before {
  content: "";
  flex: none;
  width: 0.45em;
  height: 0.45em;
  border-right: 2px solid var(--muted);
  border-bottom: 2px solid var(--muted);
  transform: rotate(-45deg);
  transition: transform 0.15s ease;
}

.prose details[open] > summary::before {
  transform: rotate(45deg);
}

.prose details[open] > summary {
  border-bottom: 1px solid var(--border);
  margin-bottom: 0.75em;
}

.prose details > :last-child {
  margin-bottom: 0.75em;
}

@media (prefers-reduced-motion: reduce) {
  .prose summary::before { transition: none; }
}

/* Block diagrams: inline SVG inside figure.diagram.
   Shapes use classes only, never hard-coded colours, so diagrams follow the theme and
   print cleanly. Coordinates are in a viewBox; width scales to the column.
   Classes: d-box (neutral block), d-box--accent (the component being discussed),
   d-box--muted (optional/external), d-group (dashed container), d-text, d-text--small,
   d-text--muted, d-arrow (line with marker-end="url(#arrow)"), d-arrow--dashed,
   d-lane (timeline lane background). Define the arrow marker once per svg:
   <defs><marker id="arrow" ...><path class="d-arrowhead" .../></marker></defs> */
.prose figure.diagram {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 0.75rem;
  padding: var(--space-4);
  margin: var(--space-5) auto;
}

.prose figure.diagram svg {
  display: block;
  width: 100%;
  height: auto;
  margin: 0 auto;
  overflow: visible;
}

.prose .diagram .d-box {
  fill: var(--surface);
  stroke: var(--fg);
  stroke-width: 1.25;
}

.prose .diagram .d-box--accent {
  fill: color-mix(in srgb, var(--accent) 12%, var(--surface));
  stroke: var(--accent);
  stroke-width: 1.5;
}

.prose .diagram .d-box--muted {
  fill: var(--subtle);
  stroke: var(--border);
}

.prose .diagram .d-group {
  fill: none;
  stroke: var(--muted);
  stroke-width: 1;
  stroke-dasharray: 5 4;
}

.prose .diagram .d-lane {
  fill: var(--subtle);
  stroke: none;
}

.prose .diagram .d-text {
  fill: var(--fg);
  font-family: var(--font-ui);
  font-size: 14px;
  font-weight: 600;
}

.prose .diagram .d-text--small {
  fill: var(--fg);
  font-family: var(--font-ui);
  font-size: 12px;
  font-weight: 400;
}

.prose .diagram .d-text--muted {
  fill: var(--muted);
  font-family: var(--font-ui);
  font-size: 12px;
  font-weight: 400;
}

.prose .diagram .d-arrow {
  fill: none;
  stroke: var(--muted);
  stroke-width: 1.5;
}

.prose .diagram .d-arrow--dashed {
  stroke-dasharray: 5 4;
}

.prose .diagram .d-arrowhead {
  fill: var(--muted);
}

@media print {
  .prose figure.diagram {
    break-inside: avoid;
    border-color: #999;
  }
}