/* Public Timeline V3 year-index tabs. */
.aa-timeline-controls {
	margin-bottom: clamp(1.25rem, 2.4vw, 1.9rem);
}

.aa-timeline-index {
	--aa-index-tab-height: 33px;
	--aa-index-tab-width: 116px;
	--aa-index-tab-shoulder: 11px;
	max-width: 980px;
	margin: 0 auto;
	padding: .6rem 0 clamp(3rem, 7vw, 5rem);
}

/*
 * This is an index tab, not a folder shell: each year has one tab edge and
 * one rule only. The lower edge stays open so the tab grows out of the rule.
 */
.aa-timeline-index-year {
	margin: 0;
}

.aa-timeline-index-year + .aa-timeline-index-year {
	margin-top: clamp(1rem, 2.2vw, 1.5rem);
}

.aa-timeline-index-toggle {
	display: grid;
	grid-template-columns: var(--aa-index-tab-width) minmax(1rem, 1fr) auto;
	align-items: center;
	width: 100%;
	min-height: 52px;
	padding: 0;
	border: 0;
	border-radius: 0;
	background: transparent;
	color: var(--aa-text);
	font-family: var(--aa-sans-stack);
	text-align: left;
	cursor: pointer;
}

.aa-timeline-index-toggle:hover {
	background: transparent;
	color: var(--aa-text);
}

.aa-timeline-index-tab {
	position: relative;
	z-index: 1;
	display: flex;
	align-items: center;
	align-self: end;
	width: calc(var(--aa-index-tab-width) + var(--aa-index-tab-shoulder));
	height: var(--aa-index-tab-height);
	margin-bottom: 10px;
	margin-right: calc(var(--aa-index-tab-shoulder) * -1);
	padding: 0 .75rem;
	background: var(--aa-bg);
	border-top: 1px solid var(--aa-line);
	border-left: 1px solid var(--aa-line);
	clip-path: polygon(0 0, calc(100% - var(--aa-index-tab-shoulder)) 0, 100% 100%, 0 100%);
	font-family: var(--aa-display-font);
	font-size: 1.15rem;
	font-weight: 400;
	letter-spacing: -.03em;
	line-height: 1;
	transition: background-color .18s ease, color .18s ease, transform .18s ease;
}

.aa-timeline-index-tab::after {
	position: absolute;
	top: 0;
	right: var(--aa-index-tab-shoulder);
	width: 1px;
	height: calc(var(--aa-index-tab-height) + 1px);
	background: var(--aa-line);
	content: "";
	transform: skewX(19deg);
	transform-origin: top;
}

.aa-timeline-index-rule {
	align-self: end;
	height: 1px;
	margin: 0 0 10px calc(var(--aa-index-tab-shoulder) + 1px);
	background: var(--aa-line);
}

.aa-timeline-index-meta {
	display: flex;
	align-items: center;
	justify-content: flex-end;
	gap: clamp(.6rem, 1.4vw, 1rem);
	padding: 0 0 10px 1rem;
	color: var(--aa-muted);
	font-size: .64rem;
	letter-spacing: .01em;
	line-height: 1.2;
	white-space: nowrap;
}

.aa-timeline-index-action {
	color: var(--aa-text);
	text-decoration: underline;
	text-decoration-thickness: 1px;
	text-underline-offset: .18em;
}

.aa-timeline-index-year.is-open .aa-timeline-index-tab {
	background: var(--aa-text);
	color: var(--aa-paper);
	transform: translateY(-3px);
}

.aa-timeline-index-year.is-open .aa-timeline-index-tab::after,
.aa-timeline-index-year.is-open .aa-timeline-index-rule {
	background: var(--aa-text);
}

.aa-timeline-index-year.is-open .aa-timeline-index-tab {
	border-color: var(--aa-text);
}

.aa-timeline-index-toggle:focus-visible {
	outline: 0;
}

.aa-timeline-index-toggle:focus-visible .aa-timeline-index-tab {
	outline: 2px solid var(--aa-text);
	outline-offset: 3px;
}

.aa-timeline-index-year.is-open .aa-timeline-index-toggle:focus-visible .aa-timeline-index-tab {
	outline-color: var(--aa-paper);
	box-shadow: 0 0 0 4px var(--aa-text);
}

/* The formal Timeline rows appear in open page space; no Lab shell is drawn. */
.aa-timeline-index-panel {
	padding: clamp(1.5rem, 3vw, 2.15rem) 0 clamp(1.75rem, 3.5vw, 2.6rem);
}

.aa-timeline-index-items.aa-timeline-items {
	padding: 0;
}

@media (max-width: 860px) {
	.aa-timeline-index {
		--aa-index-tab-height: 31px;
		--aa-index-tab-width: 96px;
		--aa-index-tab-shoulder: 9px;
		padding-top: .4rem;
	}

	.aa-timeline-index-toggle {
		grid-template-columns: var(--aa-index-tab-width) minmax(1rem, 1fr);
		min-height: 57px;
	}

	.aa-timeline-index-tab,
	.aa-timeline-index-rule {
		margin-bottom: 0;
	}

	.aa-timeline-index-meta {
		grid-column: 1 / -1;
		justify-content: flex-start;
		padding: .7rem 0 0;
		font-size: .67rem;
		white-space: normal;
	}

	.aa-timeline-index-panel {
		padding-top: 1.55rem;
	}
}

@media (prefers-reduced-motion: reduce) {
	.aa-timeline-index-tab {
		transition: none;
	}
}