/* Flow diagrams. Colors come from --fd-* on the figure; an unmapped host
   falls back to currentColor and Canvas. Every class starts with fd-. */

.fd {
  container-type: inline-size;
  container-name: fd;
  position: relative;
  margin: 1.75rem 0 0;
  color: var(--fd-text, currentColor);
  font-family: var(--fd-font, inherit);
  --fd-gap: 28px;
}

.fd-svg {
  display: block;
  width: 100%;
  height: auto;
  overflow: visible;
}

.fd-svg [data-tone="neutral"] { --fd-tone: var(--fd-faint, currentColor); }
.fd-svg [data-tone="accent"] { --fd-tone: var(--fd-accent, currentColor); }
.fd-svg [data-tone="warn"] { --fd-tone: var(--fd-warn, currentColor); }
.fd-svg [data-tone="info"] { --fd-tone: var(--fd-info, currentColor); }

.fd-box {
  fill: var(--fd-surface, Canvas);
  stroke: var(--fd-edge, currentColor);
  stroke-width: 1;
}

.fd-svg [data-tone="accent"] .fd-box,
.fd-svg [data-tone="warn"] .fd-box,
.fd-svg [data-tone="info"] .fd-box {
  stroke: color-mix(in srgb, var(--fd-tone) 46%, var(--fd-edge, currentColor));
}

.fd-svg [data-kind="core"] .fd-box {
  stroke: color-mix(in srgb, var(--fd-tone, var(--fd-accent, currentColor)) 72%, var(--fd-edge, currentColor));
  stroke-width: 1.6;
}

.fd-svg [data-selected="true"] .fd-box {
  fill: color-mix(in srgb, var(--fd-accent, currentColor) 14%, var(--fd-surface, Canvas));
  stroke: var(--fd-accent, currentColor);
}

.fd-lbl {
  fill: var(--fd-text, currentColor);
  font-weight: 600;
}

.fd-lbl-core { font-weight: 800; }

.fd-sub { fill: var(--fd-faint, currentColor); }

.fd-idx,
.fd-zone,
.fd-boundary-label,
.fd-tick,
.fd-step,
.fd-status {
  font-family: var(--fd-mono, ui-monospace, SFMono-Regular, Menlo, Consolas, monospace);
}

.fd-idx {
  fill: var(--fd-tone, currentColor);
  font-weight: 700;
  letter-spacing: 0.08em;
}

.fd-svg [data-tone="accent"] .fd-idx {
  fill: var(--fd-accent-ink, var(--fd-accent, currentColor));
}

.fd-lane {
  fill: var(--fd-faint, currentColor);
  font-weight: 600;
}

.fd-svg [data-selected="true"] .fd-lane {
  fill: var(--fd-accent-ink, var(--fd-accent, currentColor));
}

.fd-zone,
.fd-boundary-label {
  fill: var(--fd-faint, currentColor);
  font-weight: 700;
  letter-spacing: 0.08em;
}

.fd-boundary-label { fill: var(--fd-warn, currentColor); }

.fd-boundary {
  fill: none;
  stroke: var(--fd-warn, currentColor);
  stroke-width: 1.4;
  stroke-opacity: 0.8;
  stroke-dasharray: 5 9;
  animation: fd-crawl 2.6s linear infinite;
}

.fd-wire {
  fill: none;
  stroke: var(--fd-edge, currentColor);
  stroke-width: 1.4;
}

.fd-flow {
  fill: none;
  stroke: var(--fd-accent, currentColor);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-opacity: 0.9;
  stroke-dasharray: 13 19;
  animation: fd-flow 2.4s linear infinite;
}

.fd-flow[data-selected="true"] { stroke-width: 2.6; stroke-opacity: 1; }
.fd-flow[data-delay="1"] { animation-delay: -0.4s; }
.fd-flow[data-delay="2"] { animation-delay: -0.8s; }
.fd-flow[data-delay="3"] { animation-delay: -1.2s; }
.fd-flow[data-delay="4"] { animation-delay: -1.6s; }
.fd-flow[data-delay="5"] { animation-delay: -2s; }

.fd-halo {
  fill: none;
  stroke: var(--fd-accent, currentColor);
  stroke-width: 1.6;
  stroke-opacity: 0.45;
  stroke-linecap: round;
  stroke-dasharray: 2 12;
  animation: fd-orbit 16s linear infinite;
}

.fd-pulse {
  fill: var(--fd-accent, currentColor);
  transform-box: fill-box;
  transform-origin: center;
  animation: fd-pulse 2.6s ease-out infinite;
}

.fd-bar { fill: color-mix(in srgb, var(--fd-accent, currentColor) 22%, transparent); }

.fd-bar-fill {
  fill: var(--fd-accent, currentColor);
  transform: scaleX(0.62);
  transform-box: fill-box;
  transform-origin: left center;
  animation: fd-fill 6s ease-in-out infinite;
}

/* One status line. The old line reaches opacity 0 before the next iteration. */
.fd-tick,
.fd-status {
  animation: fd-tick 2.48s linear infinite;
}

.fd-tick {
  fill: var(--fd-accent-ink, var(--fd-accent, currentColor));
  font-weight: 600;
}

.fd-status {
  display: none;
  margin: 0.85rem 0 0;
  color: var(--fd-accent-ink, var(--fd-accent, currentColor));
  font-size: 0.78rem;
  font-weight: 600;
  letter-spacing: 0.01em;
}

@keyframes fd-flow { to { stroke-dashoffset: -64; } }
@keyframes fd-crawl { to { stroke-dashoffset: -28; } }
@keyframes fd-orbit { to { stroke-dashoffset: -280; } }

@keyframes fd-pulse {
  0% { transform: scale(0.55); opacity: 0.75; }
  100% { transform: scale(2.1); opacity: 0; }
}

@keyframes fd-fill {
  0%, 100% { transform: scaleX(0.36); }
  45% { transform: scaleX(0.84); }
}

@keyframes fd-tick {
  /* 2480ms: fade 280, hold 1760, out 280, gap 160 */
  0% { opacity: 0; }
  11.2903% { opacity: 1; }
  82.2581% { opacity: 1; }
  93.5484% { opacity: 0; }
  100% { opacity: 0; }
}

@keyframes fd-dash-y { to { background-position: 0 12px; } }

@keyframes fd-travel-y {
  0% { transform: translateY(0); opacity: 0; }
  14% { opacity: 1; }
  82% { opacity: 1; }
  100% { transform: translateY(var(--fd-gap)); opacity: 0; }
}

.fd.is-paused .fd-flow,
.fd.is-paused .fd-halo,
.fd.is-paused .fd-pulse,
.fd.is-paused .fd-boundary,
.fd.is-paused .fd-bar-fill,
.fd.is-paused .fd-tick,
.fd.is-paused .fd-status,
.fd.is-paused .fd-link::before,
.fd.is-paused .fd-link::after {
  animation-play-state: paused;
}

.fd.is-static .fd-tick,
.fd.is-static .fd-status {
  animation: none;
  opacity: 1;
}

.fd-legend {
  display: grid;
  grid-auto-flow: column;
  grid-auto-columns: minmax(0, 1fr);
  gap: var(--fd-gap);
  margin: 1.4rem 0 0;
  padding: 0;
  list-style: none;
}

.fd-node {
  position: relative;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding-top: 14px;
  border-top: 1px solid var(--fd-edge, currentColor);
}

.fd-node[data-tone="neutral"] { --fd-tone: var(--fd-faint, currentColor); }
.fd-node[data-tone="accent"] { --fd-tone: var(--fd-accent-ink, var(--fd-accent, currentColor)); }
.fd-node[data-tone="warn"] { --fd-tone: var(--fd-warn, currentColor); }
.fd-node[data-tone="info"] { --fd-tone: var(--fd-info, currentColor); }

.fd-head {
  display: flex;
  align-items: center;
  gap: 10px;
}

.fd-chip {
  display: inline-flex;
  width: 34px;
  height: 34px;
  flex: 0 0 auto;
  align-items: center;
  justify-content: center;
  border-radius: 10px;
  background: color-mix(in srgb, var(--fd-tone, currentColor) 14%, transparent);
  color: var(--fd-tone, currentColor);
}

.fd-icon { display: block; }

.fd-step {
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  color: var(--fd-faint, currentColor);
}

.fd-title {
  margin: 0;
  font-size: 0.98rem;
  font-weight: 600;
  line-height: 1.3;
  color: var(--fd-text, currentColor);
}

.fd-note {
  margin: 0;
  font-size: 0.82rem;
  line-height: 1.45;
  color: var(--fd-faint, currentColor);
  text-wrap: pretty;
}

.fd-link { display: none; }

.fd-ticks,
.fd-zones {
  margin: 0.75rem 0 0;
  padding: 0;
  list-style: none;
}

.fd-ticks li::before { content: "\25B2\00a0"; }

.fd-ticks {
  color: var(--fd-accent-ink, var(--fd-accent, currentColor));
  font-family: var(--fd-mono, ui-monospace, SFMono-Regular, Menlo, Consolas, monospace);
  font-size: 0.78rem;
  font-weight: 600;
}

.fd-zones {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem 1rem;
  color: var(--fd-faint, currentColor);
  font-family: var(--fd-mono, ui-monospace, SFMono-Regular, Menlo, Consolas, monospace);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.06em;
}

.fd > figcaption {
  margin: 0.85rem 0 0;
  color: var(--fd-text, currentColor);
  font-weight: 600;
  font-size: 0.84rem;
  line-height: 1.45;
  text-wrap: pretty;
}

/* A diagram's section heading wraps to even lines, never one word alone. */
section:has(figure.fd) h2 { text-wrap: balance; }

.fd.is-drawn .fd-ticks,
.fd.is-drawn .fd-zones {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  clip-path: inset(50%);
  white-space: nowrap;
  border: 0;
}

.fd-story + .fd-story { margin-top: 3.25rem; }
.fd-story > h3 { margin: 0 0 0.3rem; }
.fd-story > p { margin: 0; }

@container fd (max-width: 860px) {
  .fd { --fd-gap: 22px; }

  .fd-svg { display: none; }

  .fd.is-drawn .fd-status { display: block; }

  .fd.is-drawn .fd-zones {
    position: static;
    width: auto;
    height: auto;
    margin: 0 0 0.75rem;
    overflow: visible;
    clip: auto;
    clip-path: none;
    white-space: normal;
  }

  .fd-legend {
    grid-auto-flow: row;
    grid-template-columns: minmax(0, 1fr);
    margin-top: 0;
  }

  .fd-node {
    padding: 16px;
    border: 1px solid var(--fd-edge, currentColor);
    border-radius: 14px;
    background: var(--fd-surface, Canvas);
  }

  .fd-node[data-tone="accent"],
  .fd-node[data-tone="warn"],
  .fd-node[data-tone="info"] {
    border-color: color-mix(in srgb, var(--fd-tone, currentColor) 42%, var(--fd-edge, currentColor));
  }

  .fd-link {
    display: block;
    position: absolute;
    left: 32px;
    bottom: calc(-1 * var(--fd-gap));
    width: 8px;
    height: var(--fd-gap);
  }

  .fd-link::before {
    content: "";
    position: absolute;
    left: 3px;
    top: 0;
    bottom: 0;
    width: 2px;
    background-image: linear-gradient(180deg, var(--fd-edge, currentColor) 0 6px, transparent 6px 12px);
    background-size: 2px 12px;
    animation: fd-dash-y 1.6s linear infinite;
  }

  .fd-link::after {
    content: "";
    position: absolute;
    top: -3px;
    left: 1px;
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--fd-accent, currentColor);
    animation: fd-travel-y 2.8s ease-in-out infinite;
  }
}

@media (prefers-reduced-motion: reduce) {
  .fd-flow,
  .fd-halo,
  .fd-pulse,
  .fd-boundary,
  .fd-bar-fill,
  .fd-tick,
  .fd-status,
  .fd-link::before,
  .fd-link::after {
    animation: none;
  }

  .fd-tick,
  .fd-status { opacity: 1; }

  .fd-bar-fill { transform: scaleX(0.62); }

  .fd-pulse { opacity: 1; transform: none; }

  .fd-link::after { opacity: 1; transform: none; }
}

@media (forced-colors: active) {
  .fd {
    --fd-surface: Canvas;
    --fd-edge: CanvasText;
    --fd-text: CanvasText;
    --fd-faint: CanvasText;
    --fd-accent: CanvasText;
    --fd-accent-ink: CanvasText;
    --fd-warn: CanvasText;
    --fd-info: CanvasText;
    --fd-tone: CanvasText;
  }

  .fd-svg [data-tone] { --fd-tone: CanvasText; }

  .fd-flow,
  .fd-halo,
  .fd-boundary,
  .fd-wire { stroke: CanvasText; }

  .fd-pulse,
  .fd-bar-fill,
  .fd-tick,
  .fd-idx,
  .fd-boundary-label { fill: CanvasText; }

  .fd-bar { fill: Canvas; stroke: CanvasText; }

  .fd-svg [data-selected="true"] .fd-box {
    fill: Canvas;
    stroke: Highlight;
    stroke-width: 2.4;
  }

  .fd-svg [data-selected="true"] .fd-lane,
  .fd-flow[data-selected="true"] {
    fill: Highlight;
    stroke: Highlight;
  }

  .fd-node {
    background: Canvas;
    color: CanvasText;
    border-color: CanvasText;
  }

  .fd-chip {
    background: Canvas;
    color: CanvasText;
    forced-color-adjust: none;
  }
}