* {
	box-sizing: border-box;
}

body {
	font-family: var(--font-family-system-sans);
	font-size: var(--font-size-medium);
	line-height: var(--line-height-medium);
	color: var(--color-base);
	background-color: var(--background-color-base);
	width: 100vw;
	height: 100vh;
	margin: 0;
	padding: 0;
	overflow: auto hidden;
	accent-color: var(--color-progressive);
	display: grid;
	grid-template-columns: 40ch auto;
	grid-template-areas:
		"header  header"
		"nav     main";
	align-items: start;
	align-content: start;
	transition:
		background-color var(--transition-duration-medium)
		var(--transition-timing-function-system),
		color var(--transition-duration-medium)
		var(--transition-timing-function-system);
}

p,
li,
h1,
h2,
h3,
h4,
h5,
h6 {
	margin: 0;
	padding: 0;
	max-inline-size: 60ch;
}

input,
select,
button {
	font-family: var(--font-family-system-sans);
	font-size: var(--font-size-medium);
	padding: var(--spacing-50) var(--spacing-75);
}

/* ── Header ── */
.header {
	display: grid;
	grid-area: header;
	grid-template-columns: 50px auto 50px;
	gap: var(--spacing-100);
	background-color: var(--background-color-neutral);
	border-bottom: var(--border-width-base) solid var(--border-color-subtle);
	place-items: center stretch;
	height: 3lh;
	width: 100%;
	padding: var(--spacing-50) var(--spacing-75);
	z-index: var(--z-index-toolbar);

	.site-title {
		font-size: var(--font-size-large);
		font-weight: var(--font-weight-bold);
		color: var(--color-emphasized);
	}

	.logo {
		background-image: url("./logo.svg");
		background-repeat: no-repeat;
		background-size: 48px;
		background-position: center left;
		width: 50px;
		height: 50px;
	}
}

/* ── Nav sidebar ── */
.nav {
	grid-area: nav;
	background-color: var(--background-color-base);
	border-inline-end: var(--border-width-base) solid var(--border-color-subtle);
	display: grid;
	align-items: start;
	align-content: start;
	gap: var(--spacing-50);
	max-height: 100vh;
	overflow: hidden auto;
	padding: var(--spacing-100);

	> * {
		display: block;
	}

	h4 {
		margin: 0;
		padding: var(--spacing-50) 0 0;
		font-size: var(--font-size-small);
		font-weight: var(--font-weight-semibold);
		color: var(--color-subtle);
		text-transform: uppercase;
		letter-spacing: 0.06em;
	}

	ul {
		list-style: none;
		padding: 0;
		margin: 0;

		li {
			margin: 0;
			padding: var(--spacing-25) var(--spacing-100);
		}
	}

	a {
		text-decoration: none;
		text-wrap: nowrap;
		color: var(--color-base);
		font-weight: var(--font-weight-normal);
		transition: color var(--transition-duration-base)
			var(--transition-timing-function-system);

		&:hover {
			color: var(--color-progressive--hover);
		}

		&:visited {
			color: var(--color-base);
		}
	}

	a.active {
		font-weight: var(--font-weight-bold);
		color: var(--color-progressive);
	}
}

/* ── Main content area ── */
main {
	grid-area: main;
	height: auto;
	width: 100%;
	overflow: hidden auto;
	max-height: 100vh;
	padding-bottom: 10ch;
}

article {
	padding: var(--spacing-50);
	margin: var(--spacing-50) var(--spacing-100);
	overflow: hidden auto;
	max-width: 100%;

	> * {
		margin: var(--spacing-100) 0;
	}

	h2,
	h3 {
		color: var(--color-emphasized);
		font-weight: var(--font-weight-bold);
	}

	h3 {
		font-size: var(--font-size-x-large);
		line-height: var(--line-height-x-large);
	}

	h4 {
		font-size: var(--font-size-medium);
		font-weight: var(--font-weight-semibold);
		color: var(--color-base);
	}

	a {
		color: var(--color-progressive);
		text-decoration: none;

		&:hover {
			text-decoration: underline;
		}

		&:visited {
			color: var(--color-visited);
		}
	}

	code {
		font-family: var(--font-family-monospace);
		font-size: var(--font-size-small);
		background-color: var(--background-color-neutral);
		border: var(--border-width-base) solid var(--border-color-subtle);
		border-radius: var(--border-radius-base);
		padding: 0.1em 0.35em;
	}

	pre code {
		background: none;
		border: none;
		padding: 0;
		font-size: inherit;
	}

	ul {
		padding-inline-start: var(--spacing-150);

		li {
			max-inline-size: 60ch;
		}
	}
}

/* ── In-article table of contents ── */
.article-nav {
	h2 {
		font-size: var(--font-size-small);
		font-weight: var(--font-weight-semibold);
		color: var(--color-subtle);
		text-transform: uppercase;
		letter-spacing: 0.06em;
	}

	ul {
		list-style: none;
		padding: 0;
		margin: 0;

		li {
			margin: 0;
			padding: var(--spacing-25) var(--spacing-50);
		}
	}

	a {
		text-decoration: none;
		text-wrap: nowrap;
		font-size: var(--font-size-small);
		color: var(--color-progressive);

		&:visited {
			color: var(--color-progressive);
		}
	}
}

/* ── Subheading ── */
.subheading {
	color: var(--color-subtle);
	font-weight: var(--font-weight-normal);
}

/* ── Example blocks ── */
.example {
	display: grid;
	grid-template-columns: 1fr;
	grid-template-rows: auto;
	gap: var(--spacing-50);
	overflow: hidden;
	max-inline-size: min(100vw, 1000px);
	border: var(--border-width-base) solid var(--border-color-subtle);
	border-radius: var(--border-radius-base);
	padding: var(--spacing-75);
	background-color: var(--background-color-neutral-subtle);

	.rendering {
		resize: both;
		overflow: auto;
	}
}

/* ── Utility layout helpers ── */
.flex {
	display: flex;
	gap: var(--spacing-100);
}

.grid {
	display: grid;
}

/* ── Buttons ── */
button {
	background-color: var(--background-color-progressive);
	color: var(--color-inverted);
	border: var(--border-width-base) solid var(--border-color-progressive);
	border-radius: var(--border-radius-base);
	font-weight: var(--font-weight-semibold);
	cursor: pointer;
	transition:
		background-color var(--transition-duration-base)
		var(--transition-timing-function-system),
		border-color var(--transition-duration-base)
		var(--transition-timing-function-system);

	&:hover {
		background-color: var(--background-color-progressive--hover);
		border-color: var(--border-color-progressive--hover);
	}

	&:active {
		background-color: var(--background-color-progressive--active);
		border-color: var(--border-color-progressive--active);
	}

	&:focus-visible {
		outline: var(--border-width-thick) solid
			var(--outline-color-progressive--focus);
		outline-offset: 2px;
	}
}

/* ── Form inputs & selects ── */
input[type="text"],
input[type="search"],
select {
	background-color: var(--background-color-base);
	color: var(--color-base);
	border: var(--border-width-base) solid var(--border-color-input);
	border-radius: var(--border-radius-base);

	&:hover {
		border-color: var(--border-color-input--hover);
	}

	&:focus {
		outline: none;
		border-color: var(--border-color-input--focus);
		box-shadow: inset 0 0 0 1px var(--border-color-input--focus);
	}
}

/* ── Footer ── */
.footer {
	padding: var(--spacing-100);
	border-top: var(--border-width-base) solid var(--border-color-subtle);
	background-color: var(--background-color-neutral);
	width: 100%;
	z-index: var(--z-index-above-content);
}

/* ── Mobile hamburger menu ── */
.hamburger {
	display: none;
	justify-self: end;
	margin: var(--spacing-100);
	width: 30px;
	height: 30px;
	cursor: pointer;

	span {
		display: block;
		width: 100%;
		height: 3px;
		background-color: var(--color-base);
		margin-bottom: 5px !important;
		transition: var(--transition-duration-base);
	}
}

#menu-toggle:checked {
	+ .hamburger span:nth-child(1) {
		transform: rotate(45deg) translate(5px, 5px);
	}

	+ .hamburger span:nth-child(2) {
		opacity: 0;
	}

	+ .hamburger span:nth-child(3) {
		transform: rotate(-45deg) translate(7px, -7px);
	}
}

@media (width <= 100ch) {
	body {
		grid-template-areas:
			"header"
			"main";
		grid-template-columns: auto;

		&:has(#menu-toggle:checked) {
			overflow: hidden;

			.nav {
				height: 100%;
				right: 0;
				left: 0;
				top: 72px;
				z-index: var(--z-index-overlay);
			}
		}
	}

	main {
		grid-template-columns: 1fr;
	}

	article {
		margin: 0;
		padding: var(--spacing-50);
	}

	.example {
		grid-template-columns: 1fr;

		code {
			border: none;
		}
	}

	.header {
		position: sticky;
		top: 0;
		z-index: var(--z-index-overlay);
	}

	.nav {
		position: fixed;
		right: 0;
		left: 100vw;
		transition: var(--transition-duration-base);
		padding: var(--spacing-200);
		background-color: var(--background-color-base);
	}

	.hamburger {
		display: block;
	}
}

@view-transition {
	navigation: auto;
}