/* ==========================================================================
   abcBIM — learn.css
   Learn archive (/learn/, /learn/topic/{term}/) and single lesson.
   Reuses base.css components (.page-hero, .tabs, .lesson-feature, .lesson-grid,
   .lesson-card, .lesson-list, .lesson-item, .media-frame, .watch-pill,
   .section-head, .empty-state, .btn). Only .learn-* rules live here.
   ========================================================================== */

/* ---------- Archive ---------- */
.learn-archive {
	padding-bottom: var(--section-y);
}

/* Featured lesson: stacked below 900px, wide two-column above. */
.learn-featured {
	margin-top: 40px;
}

/* Larger title on the archive (base.css sizes .lesson-feature__heading; the link inherits). */
.learn-featured .lesson-feature__heading {
	font-size: clamp(28px, 3vw, 42px);
	line-height: 1.1;
}

@media (min-width: 900px) {
	/*
	 * Media on the left (~60%) spanning every row; the text column sits in the
	 * middle rows, with the two 1fr rows taking up the remaining height so the
	 * text is vertically centred against the 16:9 frame.
	 */
	.learn-featured .lesson-feature {
		display: grid;
		grid-template-columns: minmax(0, 3fr) minmax(0, 2fr);
		grid-template-rows: 1fr auto auto auto auto 1fr;
		column-gap: clamp(32px, 4vw, 64px);
		row-gap: 0;
	}

	.learn-featured .lesson-feature__media {
		grid-column: 1;
		grid-row: 1 / 7;
		align-self: center;
	}

	.learn-featured .lesson-feature__meta {
		grid-column: 2;
		grid-row: 2;
		margin-top: 0;
	}

	.learn-featured .lesson-feature__heading {
		grid-column: 2;
		grid-row: 3;
		margin-top: 16px;
	}

	.learn-featured .lesson-feature__excerpt {
		grid-column: 2;
		grid-row: 4;
		margin-top: 16px;
		font-size: 17px;
	}

	.learn-featured .lesson-feature > .text-link {
		grid-column: 2;
		grid-row: 5;
		justify-self: start;
		margin-top: 22px;
	}
}

.learn-grid {
	margin-top: 40px;
}

.learn-featured + .learn-grid {
	margin-top: 56px;
	padding-top: 56px;
	border-top: 1px solid var(--c-rule);
}

.learn-empty {
	margin-top: 8px;
}

/* ---------- Single lesson ---------- */
.learn-single {
	padding-top: clamp(28px, 4vw, 56px);
	padding-bottom: var(--section-y-tight);
}

.learn-single__meta {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	gap: 6px 12px;
	margin-top: clamp(28px, 4vw, 44px);
	font-family: var(--f-mono);
	font-size: 11.5px;
	letter-spacing: 0.08em;
	text-transform: uppercase;
	color: var(--c-muted);
}

.learn-single__meta > * + *::before {
	content: "·";
	margin-right: 12px;
	color: var(--c-muted);
}

.learn-single__topic {
	color: var(--c-green);
}

a.learn-single__topic:hover {
	color: var(--c-ink);
}

.learn-single__title {
	max-width: 900px;
	margin-top: 18px;
	font-family: var(--f-serif);
	font-weight: 400;
	font-size: clamp(38px, 4.6vw, 64px);
	line-height: 1.04;
	letter-spacing: -0.02em;
	text-wrap: balance;
}

.learn-single__dek {
	max-width: 720px;
	margin-top: 22px;
}

.learn-single__media {
	margin-top: clamp(32px, 4vw, 56px);
}

.learn-single__body {
	margin-top: clamp(40px, 5vw, 56px);
}

.learn-single__content {
	min-width: 0;
	max-width: 720px;
	margin-inline: 0;
}

.learn-single__pages {
	margin-top: 32px;
	font-weight: 600;
}

/* "Discuss this in the community" card */
.learn-aside {
	max-width: 720px;
	margin-top: 48px;
	padding: 24px;
	background: var(--c-paper);
	border: 1px solid var(--c-rule);
	border-radius: var(--radius);
}

.learn-aside__title {
	margin-top: 12px;
	font-family: var(--f-serif);
	font-weight: 400;
	font-size: 22px;
	line-height: 1.2;
	letter-spacing: -0.01em;
	text-wrap: balance;
}

.learn-aside__copy {
	margin-top: 10px;
	font-size: 15px;
	line-height: 1.55;
	color: var(--c-slate);
}

.learn-aside__btn {
	margin-top: 20px;
}

.learn-aside__note {
	margin-top: 12px;
	font-family: var(--f-mono);
	font-size: 12px;
	color: var(--c-muted);
}

@media (min-width: 1024px) {
	.learn-single__body {
		display: grid;
		grid-template-columns: minmax(0, 720px) minmax(260px, 320px);
		justify-content: space-between;
		align-items: start;
		gap: 64px;
	}

	.learn-aside {
		position: sticky;
		top: calc(var(--header-h) + 32px);
		margin-top: 0;
	}

	.admin-bar .learn-aside {
		top: calc(var(--header-h) + 64px);
	}
}

/* Related lessons */
.learn-more {
	padding-bottom: var(--section-y-tight);
}

.learn-more > .section-head {
	padding-top: 32px;
	border-top: 1px solid var(--c-ink);
}

.learn-related {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(min(320px, 100%), 1fr));
	gap: 0 32px;
	margin-top: 32px;
	padding-top: 1px;
}

/* Rule above and below every item; the -1px overlap keeps stacked rules single. */
.learn-related > li {
	margin-top: -1px;
	border-top: 1px solid var(--c-rule);
}