.about-dialog {
  width: min(620px, calc(100vw - 32px));
  /* Grow to fit available height instead of a hard 680px cap, so the explainer
     does not force a scroll when the viewport has the room. Content still bounds
     the height, so the shorter kind/source dialogs stay compact. */
  max-height: calc(100dvh - 48px);
  padding: 0;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  color: var(--text);
  box-shadow: 0 18px 60px rgba(24, 33, 28, 0.28);
}

[data-theme="dark"] .about-dialog {
  box-shadow: 0 18px 60px rgba(0, 0, 0, 0.58);
}

.about-dialog::backdrop {
  background: rgba(24, 33, 28, 0.42);
  backdrop-filter: blur(2px);
}

[data-theme="dark"] .about-dialog::backdrop {
  background: rgba(0, 0, 0, 0.58);
}

.about-dialog-shell {
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  max-height: inherit;
}

.about-dialog-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  padding: 14px 16px 12px;
  border-bottom: 1px solid var(--line);
}

.about-dialog-header p {
  margin-top: 4px;
  color: var(--muted);
  font-size: 12px;
}

.about-dialog-body {
  display: grid;
  gap: 12px;
  overflow: auto;
  padding: 16px;
}

.about-dialog-body p {
  color: var(--text);
  line-height: 1.55;
}

.about-dialog-body a {
  color: var(--focus);
  font-weight: 700;
  text-decoration: none;
}

.about-dialog-body a:hover {
  text-decoration: underline;
}

.source-dialog-subhead {
  margin-top: 2px;
  color: var(--muted);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* About-modal visual explainer: a small stepped carousel of SVG screens that
   shows why scraping merge-mined chains recovers Bitcoin stales. */
.about-explainer {
  gap: 14px;
}

.about-lede {
  margin: 0;
  color: var(--text);
  line-height: 1.55;
}

.explainer {
  display: grid;
  gap: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
}

.explainer-screens {
  margin: 0;
  padding: 0;
  list-style: none;
}

.explainer-screen {
  display: grid;
  gap: 10px;
}

.explainer-screen[hidden] {
  display: none;
}

.explainer-screen.is-entering {
  animation: explainer-fade 0.18s ease;
}

@keyframes explainer-fade {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

.screen-figure {
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.screen-figure svg {
  display: block;
  width: 100%;
  height: auto;
}

.screen-title {
  margin: 0;
  color: var(--text);
  font-size: 14px;
  font-weight: 700;
}

.screen-copy {
  margin: 0;
  color: var(--text);
  line-height: 1.55;
}

/* SVG primitives shared across the four screens. */
.screen-figure .blk {
  stroke-width: 1.6;
}

.screen-figure .blk.k-base {
  fill: var(--surface-alt);
  stroke: var(--line-strong);
}

.screen-figure .blk.k-canonical {
  fill: var(--canonical);
  fill-opacity: 0.16;
  stroke: var(--canonical);
}

.screen-figure .blk.k-stale {
  fill: var(--stale);
  fill-opacity: 0.16;
  stroke: var(--stale);
}

.screen-figure .blk.k-unknown {
  fill: var(--unknown);
  fill-opacity: 0.16;
  stroke: var(--unknown);
}

.screen-figure .blk.k-near {
  fill: var(--near);
  fill-opacity: 0.16;
  stroke: var(--near);
}

.screen-figure .blk.k-orphan-strict {
  fill: var(--orphan-strict);
  fill-opacity: 0.16;
  stroke: var(--orphan-strict);
}

.screen-figure .blk.k-orphan-weak {
  fill: var(--orphan-weak);
  fill-opacity: 0.16;
  stroke: var(--orphan-weak);
}

.screen-figure .blk.k-dropped {
  fill: var(--surface-alt);
  fill-opacity: 0.5;
  stroke: var(--line);
  stroke-width: 1.4;
  stroke-dasharray: 5 4;
}

.screen-figure .edge {
  fill: none;
  stroke-width: 1.6;
}

.screen-figure .edge.e-base {
  stroke: var(--line-strong);
}

.screen-figure .edge.e-canonical {
  stroke: var(--canonical);
}

.screen-figure .edge.e-stale {
  stroke: var(--stale);
}

.screen-figure .edge.e-unknown {
  stroke: var(--unknown);
}

.screen-figure .edge.e-near {
  stroke: var(--near);
}

.screen-figure .edge.e-orphan-strict {
  stroke: var(--orphan-strict);
}

.screen-figure .edge.e-orphan-weak {
  stroke: var(--orphan-weak);
}

.screen-figure .edge.e-dashed {
  stroke-dasharray: 5 4;
}

.screen-figure .head {
  stroke: none;
}

.screen-figure .head.h-base {
  fill: var(--line-strong);
}

.screen-figure .head.h-canonical {
  fill: var(--canonical);
}

.screen-figure .head.h-stale {
  fill: var(--stale);
}

.screen-figure .head.h-unknown {
  fill: var(--unknown);
}

.screen-figure .head.h-near {
  fill: var(--near);
}

.screen-figure .mm-t {
  fill: var(--text);
  font-size: 12px;
  font-weight: 700;
}

.screen-figure .mm-t.mm-faded {
  fill: var(--muted);
}

.screen-figure .mm-s {
  fill: var(--text);
  font-size: 10px;
  font-weight: 700;
}

.screen-figure .mm-cap {
  fill: var(--muted);
  font-size: 9.5px;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.screen-figure .mm-cap.c-stale {
  fill: var(--stale);
}

.screen-figure .mm-cap.c-canonical {
  fill: var(--canonical);
}

.screen-figure .mm-lane {
  fill: var(--muted);
  font-size: 11px;
  font-weight: 700;
}

.explainer-controls {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.explainer-dots {
  display: flex;
  align-items: center;
  gap: 8px;
}

.explainer-dot {
  width: 9px;
  height: 9px;
  padding: 0;
  border: 1.5px solid var(--line-strong);
  border-radius: 50%;
  background: transparent;
  cursor: pointer;
  transition: background 0.12s ease, border-color 0.12s ease;
}

.explainer-dot[aria-current="true"] {
  background: var(--focus);
  border-color: var(--focus);
}

.about-credit {
  display: grid;
  gap: 6px;
  padding-top: 12px;
  border-top: 1px solid var(--line);
}

.about-credit p {
  margin: 0;
  color: var(--text);
  line-height: 1.55;
}

.about-credit-kicker {
  color: var(--muted);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.05em;
  text-transform: uppercase;
}

.about-credit-impl {
  color: var(--muted);
  font-size: 13px;
}

.about-credit-by {
  color: var(--muted);
  font-size: 13px;
}

@media (prefers-reduced-motion: reduce) {
  .explainer-screen.is-entering {
    animation: none;
  }

  .explainer-dot {
    transition: none;
  }
}