header,
footer {
	font-family: var(--displayFont);
	padding: 0.75rem 1.5rem;
}

:where(header, footer) a {
	text-decoration: none;
}

:where(header, footer) nav ul {
	list-style-type: none;
	display: flex;
	flex-wrap: wrap;
	justify-content: center;
	gap: 0 2rem;
	padding: 0;
	margin: 0;
}

:where(header, footer) nav li {
	margin: 0;
}

:where(header, footer) svg {
	fill: currentColor;
}

/**
 * Header — a sticky, translucent bar over the paper, like graypaper.com's.
 */
header {
	position: sticky;
	top: 0;
	z-index: 50;
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: 1rem;
	min-height: var(--header-height);
	background: rgba(0, 0, 0, 0.13);
	backdrop-filter: blur(4px);
	-webkit-backdrop-filter: blur(4px);
	border-bottom: 1px solid var(--rule-soft);
	font-size: 0.75rem;
	letter-spacing: 0.01em;
}

.site-title {
	font-family: var(--displayFont);
	font-size: 0.8125rem;
	font-weight: 500;
	line-height: 1;
	letter-spacing: 0.04em;
	color: var(--ink-strong);
	margin: 0;
	white-space: nowrap;
}

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

header .main-nav {
	display: none;
}

header .main-nav a {
	color: var(--accent);
}

header .main-nav a:hover {
	color: var(--ink-strong);
	text-decoration: underline;
	text-decoration-thickness: 1px;
	text-underline-offset: 0.25em;
}

header .main-nav a.active {
	color: var(--ink-strong);
	font-weight: 500;
}

/* Mobile: the nav becomes a full-screen overlay */
.main-nav {
	position: fixed;
	z-index: 2;
	top: 0;
	left: 0;
	transform: translateX(-100vw);
	visibility: hidden;
	width: 100%;
	height: 100vh;
	pointer-events: none;
	opacity: 0;
	display: flex;
	justify-content: center;
	align-items: center;
	background: var(--paper-sunk);
	background-image: url('/images/paper-texture.svg');
	background-size: 300px 300px;
	color: var(--ink);
	transition: all 0.25s cubic-bezier(0.785, 0.135, 0.15, 0.86);
}

.main-nav.open {
	transform: translateX(0);
	opacity: 1;
	pointer-events: unset;
	visibility: unset;
}

.main-nav.open li {
	--delay: 0.1s;
	opacity: 0;
	animation: slide_in_left 0.2s cubic-bezier(0.215, 0.61, 0.355, 1) forwards;
}

.main-nav a {
	color: inherit;
	font-size: 1rem;
	letter-spacing: 0.02em;
}

.main-nav.open ul {
	flex-direction: column;
	gap: 1.5rem;
}

.main-nav li:nth-of-type(1) {
	animation-delay: calc(var(--delay) * 1);
}

.main-nav li:nth-of-type(2) {
	animation-delay: calc(var(--delay) * 2);
}

.main-nav li:nth-of-type(3) {
	animation-delay: calc(var(--delay) * 3);
}

.main-nav li:nth-of-type(4) {
	animation-delay: calc(var(--delay) * 4);
}

.main-nav li:nth-of-type(5) {
	animation-delay: calc(var(--delay) * 5);
}

.main-nav li:nth-of-type(6) {
	animation-delay: calc(var(--delay) * 6);
}

.main-nav li:nth-of-type(7) {
	animation-delay: calc(var(--delay) * 7);
}

.main-nav li:nth-of-type(8) {
	animation-delay: calc(var(--delay) * 8);
}

.menu-button {
	margin: 0;
	background: transparent !important;
	color: var(--ink-muted);
	padding: 0;
	border: 0;
	width: 1.5rem;
	height: 1.5rem;
	display: flex;
	align-items: center;
	justify-content: center;
}

/* The starter's SVGs carry only a viewBox, so give them an explicit size */
.menu-button svg {
	width: 1.125rem;
	height: 1.125rem;
}

.menu-button:hover {
	color: var(--ink-strong);
}

@media (min-width: 40rem) {
	header {
		justify-content: space-between;
		padding: 0.75rem 2rem;
	}

	header .main-nav {
		display: block;
		position: static;
		opacity: 1;
		transform: none;
		height: auto;
		width: auto;
		background: none;
		pointer-events: unset;
		visibility: unset;
		color: inherit;
	}

	.menu-button {
		display: none;
	}
}

/* Footer */
footer {
	display: flex;
	flex-wrap: wrap;
	align-items: baseline;
	justify-content: space-between;
	gap: 1rem 2rem;
	padding: 1.5rem;
	border-top: 1px solid var(--rule);
	font-size: 0.6875rem;
	letter-spacing: 0.04em;
	color: var(--ink-faint);
}

footer nav a {
	text-transform: uppercase;
	letter-spacing: 0.06em;
}

footer nav ul {
	justify-content: flex-start;
	gap: 0 1.25rem;
}

footer a {
	color: var(--ink-muted);
}

footer a:hover {
	color: var(--accent);
}

footer p {
	margin: 0;
	font-size: inherit;
}

.skip-to-content-link {
	position: absolute;
	top: -6rem;
	left: 0;
	padding: 0.5em;
	opacity: 0;
	display: flex;
	justify-content: center;
	align-items: center;
	height: 3rem;
	background: var(--paper-sunk);
	color: var(--ink);
}

.skip-to-content-link:focus {
	transform: translateY(6rem);
	opacity: 1;
	z-index: 11;
}