/**
 * Site chrome: header, footer, primary structural regions.
 */

/* ---------- Header ---------- */
.site-header {
	position: sticky;
	top: 0;
	z-index: 100;
	background: rgba(10, 11, 18, 0.72);
	backdrop-filter: saturate(160%) blur(12px);
	-webkit-backdrop-filter: saturate(160%) blur(12px);
	border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.site-header__inner {
	display: flex;
	align-items: center;
	justify-content: space-between;
	gap: var(--space-5);
	min-height: var(--header-height);
	transition: min-height var(--transition-base);
}

.site-header.is-scrolled .site-header__inner {
	min-height: 54px;
}

.site-header.is-scrolled {
	background: rgba(10, 11, 18, 0.85);
	box-shadow: var(--shadow-sm);
}

.site-branding {
	display: flex;
	flex-direction: column;
	gap: 1px;
	line-height: 1.2;
}

.site-branding__name {
	font-size: 1.0625rem;
	font-weight: 800;
	letter-spacing: 0.01em;
	color: var(--color-text);
	transition: opacity var(--transition-fast);
}

.site-branding__name:hover {
	opacity: 0.85;
}

.site-branding__tagline {
	font-size: 0.75rem;
	color: var(--color-text-tertiary);
	font-weight: 500;
	letter-spacing: 0.01em;
}

.primary-nav {
	display: flex;
	align-items: center;
	gap: var(--space-6);
}

.primary-nav__menu {
	display: flex;
	align-items: center;
	gap: var(--space-5);
}

.primary-nav__menu a {
	position: relative;
	display: inline-block;
	font-size: var(--fs-sm);
	font-weight: 500;
	color: var(--color-text-secondary);
	padding: var(--space-2) 0;
	transition: color var(--transition-fast);
}

.primary-nav__menu a::after {
	content: "";
	position: absolute;
	left: 0;
	right: 100%;
	bottom: 0;
	height: 2px;
	border-radius: 2px;
	background: var(--gradient-brand);
	transition: right var(--transition-base);
}

.primary-nav__menu a:hover,
.primary-nav__menu a[aria-current="page"] {
	color: var(--color-text);
}

.primary-nav__menu a:hover::after,
.primary-nav__menu a[aria-current="page"]::after {
	right: 0;
}

.site-header__socials {
	display: flex;
	align-items: center;
	gap: var(--space-3);
}

.social-icon {
	display: inline-flex;
	align-items: center;
	justify-content: center;
	width: 32px;
	height: 32px;
	border-radius: var(--radius-md);
	color: var(--color-text-secondary);
	border: 1px solid transparent;
	transition: color var(--transition-fast), background-color var(--transition-fast), border-color var(--transition-fast);
}

.social-icon:hover {
	color: var(--color-text);
	background: rgba(var(--color-accent-rgb), 0.12);
	border-color: rgba(var(--color-accent-rgb), 0.3);
}

.social-icon svg {
	width: 17px;
	height: 17px;
}

.nav-toggle {
	display: none;
	align-items: center;
	justify-content: center;
	width: 40px;
	height: 40px;
	border-radius: var(--radius-md);
	color: var(--color-text);
}

.nav-toggle:hover {
	background: rgba(var(--color-accent-rgb), 0.12);
}

.nav-toggle svg {
	width: 22px;
	height: 22px;
}

@media (max-width: 860px) {
	.nav-toggle {
		display: inline-flex;
	}

	.primary-nav {
		position: fixed;
		inset: var(--header-height) 0 0 0;
		flex-direction: column;
		align-items: stretch;
		justify-content: flex-start;
		gap: 0;
		padding: var(--space-5);
		background: var(--color-bg);
		border-top: 1px solid var(--color-border);
		transform: translateY(-8px);
		opacity: 0;
		visibility: hidden;
		pointer-events: none;
		transition: opacity var(--transition-base), transform var(--transition-base), visibility var(--transition-base);
	}

	.primary-nav.is-open {
		opacity: 1;
		transform: translateY(0);
		visibility: visible;
		pointer-events: auto;
	}

	.primary-nav__menu {
		flex-direction: column;
		align-items: stretch;
		gap: 0;
	}

	.primary-nav__menu a {
		padding: var(--space-4) 0;
		border-bottom: 1px solid var(--color-border);
		font-size: var(--fs-md);
	}

	.site-header__socials {
		margin-top: var(--space-5);
		padding-top: var(--space-5);
		border-top: 1px solid var(--color-border);
	}
}

/* ---------- Reading progress (injected by main.js on article pages) ---------- */
.reading-progress {
	position: fixed;
	top: 0;
	left: 0;
	right: 0;
	height: 2px;
	z-index: 101;
	background: transparent;
	pointer-events: none;
}

.reading-progress__bar {
	display: block;
	height: 100%;
	width: 0%;
	background: var(--gradient-brand);
}

/* ---------- Footer ---------- */
.site-footer {
	position: relative;
	border-top: 1px solid rgba(255, 255, 255, 0.06);
	margin-top: var(--space-9);
	padding-block: var(--space-7);
}

.site-footer::before {
	content: "";
	position: absolute;
	top: -1px;
	left: 0;
	width: 160px;
	max-width: 40%;
	height: 1px;
	background: var(--gradient-brand);
	opacity: 0.6;
}

.site-footer__inner {
	display: flex;
	flex-wrap: wrap;
	align-items: flex-start;
	justify-content: space-between;
	gap: var(--space-6);
}

.site-footer__brand {
	max-width: 320px;
}

.site-footer__brand .site-branding__name {
	font-size: 1rem;
}

.site-footer__brand p {
	margin-top: var(--space-3);
	color: var(--color-text-tertiary);
	font-size: var(--fs-sm);
	line-height: var(--lh-relaxed);
}

.site-footer__links {
	display: flex;
	flex-wrap: wrap;
	gap: var(--space-7);
}

.site-footer__col h2 {
	font-size: 0.75rem;
	text-transform: uppercase;
	letter-spacing: 0.08em;
	color: var(--color-text-tertiary);
	margin-bottom: var(--space-3);
}

.site-footer__col ul {
	display: flex;
	flex-direction: column;
	gap: var(--space-2);
}

.site-footer__col a {
	font-size: var(--fs-sm);
	color: var(--color-text-secondary);
	transition: color var(--transition-fast);
}

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

.site-footer__bottom {
	margin-top: var(--space-7);
	padding-top: var(--space-5);
	border-top: 1px solid var(--color-border);
	font-size: 0.8125rem;
	color: var(--color-text-tertiary);
}

/* ---------- Page sections ---------- */
.section {
	padding-block: var(--space-8);
}

.section--tight {
	padding-block: var(--space-7);
}

.section-header {
	display: flex;
	align-items: baseline;
	justify-content: space-between;
	gap: var(--space-4);
	margin-bottom: var(--space-6);
}

.section-header__title {
	position: relative;
	display: inline-flex;
	align-items: center;
	gap: var(--space-3);
	font-size: var(--fs-xl);
	font-weight: 800;
	letter-spacing: -0.01em;
}

.section-header__title::before {
	content: "";
	display: inline-block;
	width: 3px;
	height: 1.1em;
	border-radius: 2px;
	background: var(--gradient-brand);
}

.section-header__link {
	font-size: var(--fs-sm);
	font-weight: 500;
	color: var(--color-accent);
	white-space: nowrap;
}

.section-header__link:hover {
	color: var(--color-accent-strong);
}

.eyebrow {
	display: inline-block;
	font-size: 0.75rem;
	font-weight: 700;
	text-transform: uppercase;
	letter-spacing: 0.08em;
	background: var(--gradient-brand);
	background-clip: text;
	-webkit-background-clip: text;
	-webkit-text-fill-color: transparent;
	margin-bottom: var(--space-3);
}