/* paperback.dev
 *
 * One stylesheet for the whole site, including the manual pages pandoc builds, which link it
 * after pandoc's own styles so the rules here win.
 *
 * Nothing on the page depends on colour or position to make sense: the markup is plain headings,
 * lists and links, and every interactive part carries its own state. Contrast is at least 4.5:1
 * for body text and 3:1 for large text and borders, in both schemes.
 */

:root {
	--bg: #fbf9f6;
	--surface: #ffffff;
	--surface-alt: #f3efe9;
	--border: #ded7cd;
	--text: #1f2328;
	--muted: #55606d;
	--accent: #0b5ed7;
	--accent-text: #ffffff;
	--focus: #0b5ed7;
	--radius: 10px;
	--measure: 42rem;
	--gutter: 1.25rem;
}

@media (prefers-color-scheme: dark) {
	:root {
		--bg: #12161c;
		--surface: #1a2028;
		--surface-alt: #222a34;
		--border: #333d4a;
		--text: #e6e9ee;
		--muted: #a7b1bf;
		--accent: #7fb2ff;
		--accent-text: #0b1220;
		--focus: #7fb2ff;
	}
}

*, *::before, *::after {
	box-sizing: border-box;
}

html {
	-webkit-text-size-adjust: 100%;
}

body {
	margin: 0;
	background: var(--bg);
	color: var(--text);
	font-family: "Segoe UI", -apple-system, BlinkMacSystemFont, Roboto, "Helvetica Neue", Arial, sans-serif;
	font-size: 1.0625rem;
	line-height: 1.65;
	/* Pandoc's stock template sets these three on body; the site layout wants them off. */
	max-width: none;
	padding: 0;
	hyphens: none;
}

/* Out of the way until it has focus. Never display:none, which would take it out of the tab
 * order along with the pixels. */
.skip-link {
	position: absolute;
	left: -9999px;
	top: 0;
	z-index: 10;
	padding: 0.6rem 1rem;
	background: var(--accent);
	color: var(--accent-text);
	border-radius: 0 0 var(--radius) 0;
}

.skip-link:focus {
	left: 0;
}

a {
	color: var(--accent);
	text-decoration-thickness: 1px;
	text-underline-offset: 0.15em;
}

a:hover {
	text-decoration-thickness: 2px;
}

:focus-visible {
	outline: 3px solid var(--focus);
	outline-offset: 2px;
	border-radius: 3px;
}

.site-header {
	background: var(--surface);
	border-bottom: 1px solid var(--border);
}

.site-header .wrap {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	gap: 0.5rem 1.5rem;
	padding: 0.9rem var(--gutter);
	max-width: 68rem;
	margin: 0 auto;
}

.brand {
	font-size: 1.2rem;
	font-weight: 700;
	color: var(--text);
	text-decoration: none;
	letter-spacing: -0.01em;
}

.brand:hover {
	color: var(--accent);
}

.site-nav ul {
	list-style: none;
	display: flex;
	flex-wrap: wrap;
	gap: 0.25rem 1rem;
	margin: 0;
	padding: 0;
}

.site-nav a {
	display: inline-block;
	padding: 0.2rem 0;
	color: var(--muted);
	text-decoration: none;
	border-bottom: 2px solid transparent;
}

.site-nav a:hover {
	color: var(--accent);
	border-bottom-color: var(--accent);
}

.site-nav [aria-current="page"] {
	color: var(--text);
	font-weight: 600;
	border-bottom-color: var(--accent);
}

main {
	display: block;
	max-width: 68rem;
	margin: 0 auto;
	padding: 2rem var(--gutter) 3rem;
}

main > * {
	max-width: var(--measure);
}

h1, h2, h3, h4, h5, h6 {
	line-height: 1.25;
	letter-spacing: -0.015em;
	margin: 2rem 0 0.6rem;
}

h1 {
	font-size: clamp(2rem, 5vw, 2.7rem);
	margin-top: 0.5rem;
}

h2 {
	font-size: 1.6rem;
	margin-top: 2.6rem;
	padding-bottom: 0.35rem;
	border-bottom: 1px solid var(--border);
}

h3 {
	font-size: 1.25rem;
}

h4 {
	font-size: 1.05rem;
}

p, ul, ol, dl, blockquote, table {
	margin: 0 0 1rem;
}

ul, ol {
	padding-left: 1.4rem;
}

li + li {
	margin-top: 0.25rem;
}

strong {
	font-weight: 650;
}

blockquote {
	margin-left: 0;
	padding: 0.2rem 0 0.2rem 1rem;
	border-left: 4px solid var(--border);
	color: var(--muted);
}

hr {
	border: 0;
	border-top: 1px solid var(--border);
	margin: 2.5rem 0;
}

code, pre, kbd, samp {
	font-family: "Cascadia Mono", Consolas, "SF Mono", Menlo, monospace;
	font-size: 0.9em;
}

code {
	background: var(--surface-alt);
	border-radius: 4px;
	padding: 0.1em 0.35em;
}

pre {
	background: var(--surface-alt);
	border: 1px solid var(--border);
	border-radius: var(--radius);
	padding: 0.9rem 1rem;
	overflow-x: auto;
	line-height: 1.5;
}

pre code {
	background: none;
	padding: 0;
}

kbd {
	background: var(--surface);
	border: 1px solid var(--border);
	border-bottom-width: 2px;
	border-radius: 4px;
	padding: 0.05em 0.4em;
}

table {
	border-collapse: collapse;
	width: 100%;
}

th, td {
	text-align: left;
	padding: 0.5rem 0.7rem;
	border-bottom: 1px solid var(--border);
}

th {
	background: var(--surface-alt);
}

img {
	max-width: 100%;
	height: auto;
}

.hero {
	max-width: none;
	padding: 2.5rem 0 1rem;
}

.hero h1 {
	margin-bottom: 0.5rem;
}

.lede {
	font-size: 1.2rem;
	color: var(--muted);
	max-width: var(--measure);
}

.cta {
	display: flex;
	flex-wrap: wrap;
	gap: 0.75rem;
	margin: 1.5rem 0 0;
	padding: 0;
	list-style: none;
	max-width: none;
}

.cta a {
	display: inline-block;
	padding: 0.6rem 1.2rem;
	border-radius: var(--radius);
	border: 1px solid var(--accent);
	text-decoration: none;
	font-weight: 600;
}

.cta li:first-child a {
	background: var(--accent);
	color: var(--accent-text);
}

.cta li:first-child a:hover {
	filter: brightness(1.1);
}

.cta li + li a {
	color: var(--accent);
	background: var(--surface);
}

.cta li + li a:hover {
	background: var(--surface-alt);
}

/* A grid of cards, each one a heading and a paragraph. It is still a run of headings to a screen
 * reader; the grid is only where the boxes sit. */
.cards {
	display: grid;
	grid-template-columns: repeat(auto-fit, minmax(16rem, 1fr));
	gap: 1rem;
	max-width: none;
	margin: 1.25rem 0 1rem;
}

.card {
	background: var(--surface);
	border: 1px solid var(--border);
	border-radius: var(--radius);
	padding: 1.1rem 1.2rem 1.2rem;
}

.card h3 {
	margin-top: 0;
	font-size: 1.1rem;
}

.card p:last-child, .card ul:last-child {
	margin-bottom: 0;
}

/* Long flat lists of short items, such as formats and languages. */
.columns {
	max-width: none;
	columns: 13rem;
	column-gap: 2rem;
}

.columns li {
	break-inside: avoid;
}

.release {
	background: var(--surface);
	border: 1px solid var(--border);
	border-radius: var(--radius);
	padding: 1.1rem 1.25rem 1.25rem;
	margin: 0 0 1.25rem;
	max-width: var(--measure);
}

.release h3 {
	margin-top: 0;
}

.release .subtitle {
	color: var(--muted);
	margin-top: -0.35rem;
}

.release ul {
	list-style: none;
	padding: 0;
	margin: 0.75rem 0 0;
}

.release li {
	padding: 0.35rem 0;
	border-top: 1px solid var(--border);
	margin-top: 0;
}

.release .count {
	color: var(--muted);
	font-size: 0.9rem;
}

.disclosure {
	font: inherit;
	color: var(--accent);
	background: none;
	border: 0;
	padding: 0.1rem 0;
	text-align: left;
	cursor: pointer;
	text-decoration: underline;
	text-underline-offset: 0.15em;
}

.license {
	max-width: none;
	margin-bottom: 0.4rem;
}

.license-name {
	margin: 0.6rem 0 0.2rem;
	font-size: 1rem;
	font-weight: 600;
}

.license-body pre {
	max-height: 26rem;
	white-space: pre-wrap;
}

details > summary {
	cursor: pointer;
	font-weight: 600;
	padding: 0.3rem 0;
}

.site-footer {
	border-top: 1px solid var(--border);
	background: var(--surface);
	color: var(--muted);
	font-size: 0.95rem;
}

.site-footer .wrap {
	max-width: 68rem;
	margin: 0 auto;
	padding: 1.5rem var(--gutter) 2.5rem;
}

.site-footer p {
	margin: 0 0 0.4rem;
}

#TOC {
	background: var(--surface);
	border: 1px solid var(--border);
	border-radius: var(--radius);
	padding: 1rem 1.25rem;
	margin-bottom: 2rem;
}

#TOC ul:last-child {
	margin-bottom: 0;
}

.language-bar ul {
	list-style: none;
	padding: 0;
	margin: 0 0 1.5rem;
	display: flex;
	flex-wrap: wrap;
	gap: 0.4rem 1rem;
}

.language-bar [aria-current] {
	font-weight: 700;
}

@media (prefers-reduced-motion: reduce) {
	*, *::before, *::after {
		animation-duration: 0.01ms !important;
		transition-duration: 0.01ms !important;
	}
}