/* Site header — colors from CSS variables only */

.header {
	position: fixed;
	top: 0;
	left: 0;
	width: 100%;
	display: flex;
	justify-content: space-between;
	align-items: center;
	padding: 1.25rem var(--arb-gutter);
	z-index: 1000;
	background: transparent;
	border-bottom: 0;
	opacity: 0;
	visibility: hidden;
	transform: translateY(-100%);
	font-family: var(--arb-font);
	transition: background-color 0.35s ease, border-color 0.35s ease, box-shadow 0.35s ease, padding 0.35s ease;
}

.header.is-ready {
	opacity: 1;
	visibility: visible;
	transform: none;
}

.header.is-sticky {
	padding-top: 15px;
    padding-bottom: 15px;
	background: var(--arb-text);
	border-bottom: 1px solid var(--arb-border);
	box-shadow: 0 8px 24px var(--arb-shadow);
}

.header.is-sticky .nav-link {
	font-size: 1rem;
}

.header.is-sticky img.logo__image {
    height: 3rem;
}

.logo {
	display: inline-flex;
	align-items: center;
	font-size: 1.25rem;
	font-weight: 900;
	letter-spacing: -0.02em;
	text-transform: uppercase;
	color: var(--arb-text);
	text-decoration: none;
	line-height: 1;
	transition: color 0.35s ease;
}

.logo:hover,
.logo:focus-visible {
	color: var(--arb-text);
	opacity: 0.9;
}

.header.is-sticky .logo,
.header.is-sticky .logo:hover,
.header.is-sticky .logo:focus-visible {
	color: var(--arb-bg);
}

.logo__image {
	display: block;
	height: 4rem;
	width: auto;
	max-width: 12rem;
	object-fit: contain;
	transition: filter 0.35s ease, height 0.35s;
	filter: brightness(0) invert(1);
}

/* Invert light logos when sticky on light background */
.header.is-sticky .logo__image {
	filter: none;
}

.nav-menu {
	display: flex;
	align-items: center;
}

.nav-menu__list {
	display: flex;
	align-items: center;
	gap: 2.5rem;
	list-style: none;
	margin: 0;
	padding: 0;
}

.header .nav-link {
	color: var(--arb-text) !important;
	text-decoration: none;
	font-size: 1.125rem;
	line-height: 1.5rem;
	font-weight: 600;
	opacity: 0.85;
	transition: opacity 0.3s ease, transform 0.3s ease, color 0.35s ease, font-size 0.35s ease;
}

.header.is-sticky .nav-link {
	color: var(--arb-bg) !important;
}

.header .nav-link:hover,
.header .nav-link:focus-visible,
.header .current-menu-item > .nav-link {
	opacity: 1;
}

.header .nav-link:hover,
.header .nav-link:focus-visible {
	color: var(--arb-bg) !important;
}

.header-actions {
	display: flex;
	align-items: center;
	gap: 1.75rem;
}

.lang-switcher {
	position: relative;
	user-select: none;
}

.lang-switcher__toggle {
	display: inline-flex;
	align-items: center;
	gap: 0.4rem;
	background: none;
	border: none;
	padding: 0.25rem 0;
	font-family: inherit;
	font-size: 0.85rem;
	font-weight: 700;
	color: var(--arb-text);
	cursor: pointer;
	letter-spacing: 0.02em;
	transition: color 0.35s ease;
}

.header.is-sticky .lang-switcher__toggle {
	color: var(--arb-bg);
}

.lang-switcher__toggle:hover,
.lang-switcher__toggle:focus-visible {
	opacity: 0.85;
}

.lang-switcher__chevron {
	display: inline-block;
	width: 0.45rem;
	height: 0.45rem;
	border-right: 1.5px solid currentColor;
	border-bottom: 1.5px solid currentColor;
	transform: rotate(45deg) translateY(-1px);
	transition: transform 0.25s ease;
	opacity: 0.8;
}

.lang-switcher.is-open .lang-switcher__chevron {
	transform: rotate(225deg) translateY(-1px);
}

.lang-switcher__dropdown {
	position: absolute;
	top: calc(100% + 0.6rem);
	right: 0;
	min-width: 4.5rem;
	margin: 0;
	padding: 0.35rem;
	list-style: none;
	background: var(--arb-overlay-solid);
	border: 1px solid var(--arb-border);
	border-radius: 0.5rem;
	backdrop-filter: blur(10px);
	-webkit-backdrop-filter: blur(10px);
	box-shadow: 0 10px 30px var(--arb-shadow-strong);
	z-index: 1001;
}

.header.is-sticky .lang-switcher__dropdown {
	background: var(--arb-text);
	border-color: var(--arb-border-strong);
	box-shadow: 0 10px 30px var(--arb-shadow-strong);
}

.lang-switcher__dropdown[hidden] {
	display: none;
}

.lang-switcher__option {
	display: block;
	padding: 0.45rem 0.75rem;
	color: var(--arb-text-soft);
	text-decoration: none;
	font-size: 0.85rem;
	font-weight: 700;
	border-radius: 0.3rem;
	transition: background-color 0.2s ease, color 0.2s ease;
}

.header.is-sticky .lang-switcher__option {
	color: var(--arb-bg);
}

.lang-switcher__option:hover,
.lang-switcher__option:focus-visible {
	background: var(--arb-text-faint);
	color: var(--arb-text);
}

.header.is-sticky .lang-switcher__option:hover,
.header.is-sticky .lang-switcher__option:focus-visible {
	background: var(--arb-border);
	color: var(--arb-bg);
}

.btn-contact {
	background-color: var(--arb-bg);
	color: var(--arb-text);
	padding: 0.7rem 1.6rem;
	border-radius: 5px;
	text-decoration: none;
	font-size: 0.85rem;
	font-weight: 800;
	letter-spacing: -0.01em;
	transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1), background-color 0.3s ease, color 0.3s ease;
	white-space: nowrap;
}

.header.is-sticky .btn-contact {
	background-color: var(--arb-bg);
	color: var(--arb-text);
}

.btn-contact:hover,
.btn-contact:focus-visible {
	background-color: var(--arb-hover-light);
	color: var(--arb-bg);
	transform: scale(1.04);
}

.header.is-sticky .btn-contact:hover,
.header.is-sticky .btn-contact:focus-visible {
	background-color: var(--arb-hover-dark);
	color: var(--arb-text);
}

@media (max-width: 868px) {
	.nav-menu {
		display: none;
	}
}