.c-header {
	position: sticky;
	top: 0;
	z-index: 100;
	background: var(--header-bg);
	border-bottom: 1px solid var(--color-border);
	-webkit-backdrop-filter: saturate(1.4) blur(12px);
	backdrop-filter: saturate(1.4) blur(12px);
}

.c-header__inner {
	display: flex;
	flex-wrap: wrap;
	align-items: center;
	justify-content: space-between;
	min-height: var(--header-height);
}

.c-header__brand {
	display: flex;
	align-items: center;
}

.c-header__logo {
	display: block;
	height: var(--logo-height);
	width: auto;
	filter: var(--logo-filter);
}

/* Mobile: the menu is hidden until the toggle sets aria-expanded */
.c-header__nav {
	display: none;
	flex-basis: 100%;
	padding-bottom: 1rem;
}

.c-header.is-open .c-header__nav {
	display: block;
}

.c-header__toggle {
	display: flex;
	flex-direction: column;
	gap: 0.3rem;
	padding: 0.75rem 0.5rem;
	background: none;
	border: 0;
	cursor: pointer;
}

.c-header__toggle-bar {
	display: block;
	width: 1.5rem;
	height: 2px;
	background: var(--color-text);
	transition: transform 0.2s, opacity 0.2s;
}

.c-header.is-open .c-header__toggle-bar:nth-child(1) {
	transform: translateY(calc(0.3rem + 2px)) rotate(45deg);
}

.c-header.is-open .c-header__toggle-bar:nth-child(2) {
	opacity: 0;
}

.c-header.is-open .c-header__toggle-bar:nth-child(3) {
	transform: translateY(calc(-0.3rem - 2px)) rotate(-45deg);
}

.c-nav {
	display: flex;
	flex-direction: column;
	margin: 0;
	padding: 0;
	list-style: none;
}

.c-nav__sub {
	margin: 0;
	padding-left: 1rem;
	list-style: none;
}

.c-nav__link {
	display: block;
	padding: 0.5rem 0;
	border-bottom: 2px solid transparent;
	color: var(--color-text);
	font-size: 0.95rem;
	font-weight: 500;
	letter-spacing: 0.02em;
	text-decoration: none;
	transition: border-color 0.15s;

	&:hover,
	&:focus-visible {
		border-bottom-color: var(--color-accent);
		color: var(--color-text);
		text-decoration: none;
	}
}

.c-nav__item--current > .c-nav__link,
.c-nav__item--active > .c-nav__link {
	border-bottom-color: var(--color-accent);
}

@media (min-width: 48em) {
	.c-header__toggle {
		display: none;
	}

	.c-header__nav,
	.c-header.is-open .c-header__nav {
		display: block;
		flex-basis: auto;
		padding-bottom: 0;
	}

	.c-nav {
		flex-direction: row;
		gap: 2rem;
	}
}