/* Diagrams for the cross-language query post.
 *
 * Same contract as diagrams.css and rllvm-substrate.css: nothing here hardcodes
 * a colour. The semantic tokens below are derived from Duckquill's own
 * --fg-color, so both themes follow the site automatically. The one exception
 * is --fx-warn, which still mixes against --fg-color rather than naming a red,
 * so a dark theme dims it the same way it dims everything else. */

.ffi-fig {
	--fx-ink: var(--fg-color);
	--fx-muted: color-mix(in srgb, var(--fg-color) 58%, transparent);
	--fx-rule: color-mix(in srgb, var(--fg-color) 22%, transparent);
	--fx-raised: color-mix(in srgb, var(--fg-color) 6%, transparent);
	--fx-warn: color-mix(in srgb, var(--fg-color) 80%, transparent);

	margin: 2rem 0;
	max-width: 42rem;
	font-family: var(--font-monospace-code);
}

.ffi-fig figcaption {
	max-width: 36rem;
	margin-top: 0.9rem;
	color: var(--fx-muted);
	font-family: var(--font-monospace-code);
	font-size: var(--font-size-x-small);
	line-height: 1.5;
	text-align: left;
}

.ffi-fig figcaption b {
	color: var(--fx-ink);
	font-weight: normal;
}

.ffi-fig .ffi-kicker {
	display: block;
	margin-bottom: 0.45rem;
	color: var(--fx-muted);
	font-size: var(--font-size-x-small);
	text-transform: uppercase;
	letter-spacing: 0.08em;
}

/* A language tag. Three languages, distinguished by weight and border rather
   than by hue, so the figure survives a monochrome print. */
.ffi-lang {
	display: inline-block;
	min-width: 3.4em;
	padding: 0.05rem 0.4rem;
	border: 1px solid var(--fx-rule);
	border-radius: 4px;
	font-size: var(--font-size-x-small);
	text-align: center;
	color: var(--fx-muted);
}

.ffi-lang.is-rust {
	border-style: solid;
	background: var(--fx-raised);
	color: var(--fx-ink);
}

.ffi-lang.is-c {
	border-style: dashed;
}

.ffi-lang.is-cxx {
	border-style: dotted;
}

/* ---------- crossings: one row per call, both lead directions ---------- */

.ffi-crossings {
	display: grid;
	gap: 1.4rem;
}

.ffi-crossings .ffi-group {
	display: grid;
	gap: 0.45rem;
}

.ffi-crossings ol {
	list-style: none;
	margin: 0;
	padding: 0;
	display: grid;
	gap: 0.4rem;
}

.ffi-crossings li {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	gap: 0.4rem;
	padding: 0.5rem 0.7rem;
	border: 1px solid var(--fx-rule);
	border-radius: 8px;
	background: var(--fx-raised);
	font-size: var(--font-size-x-small);
}

.ffi-crossings .ffi-fn {
	color: var(--fx-ink);
}

.ffi-crossings .ffi-arrow {
	color: var(--fx-muted);
}

.ffi-crossings .ffi-where {
	margin-left: auto;
	color: var(--fx-muted);
}

/* ---------- lifetime: two lanes, one value, one dangling read ---------- */

.ffi-life {
	display: grid;
	gap: 0;
	border: 1px solid var(--fx-rule);
	border-radius: 8px;
	overflow: hidden;
}

.ffi-life .ffi-step {
	display: grid;
	grid-template-columns: 4.2rem 1fr 0.9rem;
	align-items: center;
	gap: 0.7rem;
	padding: 0.6rem 0.8rem;
	border-bottom: 1px solid var(--fx-rule);
	font-size: var(--font-size-x-small);
}

.ffi-life .ffi-step:last-child {
	border-bottom: 0;
}

.ffi-life .ffi-side {
	color: var(--fx-muted);
	text-transform: uppercase;
	letter-spacing: 0.06em;
}

.ffi-life .ffi-what {
	color: var(--fx-ink);
}

.ffi-life .ffi-at {
	display: block;
	margin-top: 0.15rem;
	color: var(--fx-muted);
}

/* The bar in the right-hand gutter is the value's lifetime. It is drawn only
   on the steps where the ConnectionId is alive, so the gap below it is the
   whole bug: the pointer outlives the bar. */
.ffi-life .ffi-bar {
	justify-self: center;
	width: 3px;
	height: 100%;
	min-height: 2.1rem;
	border-radius: 2px;
	background: var(--fx-rule);
}

.ffi-life .ffi-step.is-alive .ffi-bar {
	background: var(--fx-ink);
}

.ffi-life .ffi-step.is-dead .ffi-bar {
	background: repeating-linear-gradient(
		to bottom,
		var(--fx-rule) 0 2px,
		transparent 2px 5px
	);
}

/* The return to C. A rule across the whole width, because this is where one
   language's guarantees stop applying. */
.ffi-life .ffi-return {
	display: flex;
	align-items: center;
	gap: 0.7rem;
	padding: 0.45rem 0.8rem;
	border-bottom: 1px solid var(--fx-rule);
	background: var(--fx-raised);
	color: var(--fx-muted);
	font-size: var(--font-size-x-small);
	text-transform: uppercase;
	letter-spacing: 0.08em;
}

.ffi-life .ffi-step.is-fault .ffi-what {
	color: var(--fx-warn);
}

.ffi-life .ffi-step.is-fault .ffi-what::after {
	content: " \2190 reads freed memory";
	color: var(--fx-muted);
	text-transform: none;
	letter-spacing: 0;
}

/* ---------- funnel: how far each step narrows the search ---------- */

.ffi-funnel {
	display: grid;
	gap: 0.5rem;
}

/* The bar and the text never share space: overlaying a label on a partial
   fill puts the fill's edge through a glyph at every width but 100%. */
.ffi-funnel .ffi-rung {
	display: grid;
	grid-template-columns: 3rem 8rem 1fr;
	align-items: center;
	gap: 0.8rem;
	font-size: var(--font-size-x-small);
}

.ffi-funnel .ffi-count {
	text-align: right;
	color: var(--fx-ink);
}

.ffi-funnel .ffi-track {
	height: 0.85rem;
	border: 1px solid var(--fx-rule);
	border-radius: 3px;
	background: var(--fx-raised);
	overflow: hidden;
}

.ffi-funnel .ffi-fill {
	display: block;
	width: var(--w);
	height: 100%;
	background: color-mix(in srgb, var(--fg-color) 30%, transparent);
}

.ffi-funnel .ffi-label {
	color: var(--fx-muted);
}

.ffi-funnel .ffi-label b {
	color: var(--fx-ink);
	font-weight: normal;
}

@media (max-width: 34rem) {
	.ffi-life .ffi-step {
		grid-template-columns: 3.2rem 1fr 0.9rem;
		gap: 0.5rem;
	}

	.ffi-crossings .ffi-where {
		margin-left: 0;
		flex-basis: 100%;
	}

	.ffi-funnel .ffi-rung {
		grid-template-columns: 2.6rem 4.5rem 1fr;
		gap: 0.5rem;
	}
}