/*
 * Site header.
 *
 * Sizes:
 *   --bar-height        the nav bar's height (fixed; never changes on scroll)
 *   --logo-h-top        logo height at the top of the page (can hang below the bar, over the hero)
 *   --logo-h-scrolled   logo height once scrolled (fits inside the bar)
 *
 * How it sticks: the header is position: sticky with a negative top equal to the
 * height of the top area (banners + top bar), so that area scrolls away and the nav
 * bar stays pinned. The bar's height never changes, so nothing on the page moves.
 *
 * script.js sets: --topbar-height, --header-pinned (the pinned nav plus sticky banners),
 * --logo-h-top-fit (a smaller top logo when the full one won't fit beside the menu),
 * body.header-overlay (the first section is dark: the nav starts transparent over it; also
 *   matched with :has() so it applies from the first paint, before the script runs),
 * .is-scrolled, .is-collapsed (links don't fit: the menu button shows instead).
 */

:root {
    --bar-bg-scrolled: rgba(0, 0, 0, .75);
    --bar-blur: 20px;
    --bar-height: 72px;
    --logo-h-top: 80px;
    --logo-h-scrolled: 50px;
    --topbar-height: 36px;
    --header-height: var(--bar-height);
}

@media (max-width: 1024px) {
    :root {
        --logo-h-scrolled: 52px;
    }
}

@media (max-width: 600px) {
    :root {
        --bar-height: 60px;
        --logo-h-top: 64px;
        --logo-h-scrolled: 44px;
    }
}

.site-header {
    position: sticky;
    top: calc(-1 * var(--topbar-height));
    z-index: 500;
    color: var(--white);
    pointer-events: none; /* the transparent space under the nav mustn't block clicks */
}

.site-header > * {
    pointer-events: auto;
}

/* Keeps the tall (top-of-page) nav's space, so shrinking it never shifts the page */
.site-header__bar-space {
    height: var(--bar-height);
    pointer-events: none;
}

/* A dark first section slides up under the transparent nav… */
body:is(.header-overlay, :has(.site-main > .is-dark:first-child)) .site-header {
    margin-bottom: calc(-1 * var(--bar-height));
}

/* …and its content starts below the nav, clearing the hanging logo by ~32px
   (the section's own top padding counts toward that). */
body:is(.header-overlay, :has(.site-main > .is-dark:first-child)) .site-main > :first-child {
    --header-clearance: max(var(--bar-height), calc((var(--bar-height) - var(--logo-h-scrolled)) / 2 + var(--logo-h-top-fit, var(--logo-h-top)) + 32px - var(--space-lg)));
}

/* ---------- Banners and top bar ---------- */

.site-header__banner {
    --banner-pad: 10px;
    background: var(--banner-bg, var(--tertiary-600));
    color: var(--banner-text, var(--white));
    font-size: 14px;
    line-height: 1.45;
}

.site-header__banner[hidden],
.site-header__topbar[hidden] {
    display: none;
}

.site-header__banner--small {
    --banner-pad: 6px;
    font-size: 13px;
}

.site-header__banner--large {
    --banner-pad: 16px;
    font-size: 16px;
}

.site-header__banner-inner {
    position: relative;
    display: flex;
    justify-content: center;
    align-items: center;
    padding-block: var(--banner-pad);
}

.site-header__banner:has(.site-header__banner-close) .site-header__banner-inner {
    padding-inline: calc(var(--gutter) + 44px);
}

.site-header__banner-body {
    display: inline-flex;
    align-items: flex-start;
    gap: 10px;
    max-width: 100%;
}

.site-header__banner-icon {
    flex-shrink: 0;
    width: 1.25em;
    height: 1.25em;
    margin-top: .05em;
}

.site-header__banner-text {
    text-align: center;
}

.site-header__banner-text :is(p, li, strong, em) {
    margin: 0;
    color: inherit;
    font-size: inherit;
    line-height: inherit;
}

.site-header__banner-text p + p {
    margin-top: 4px;
}

.site-header__banner-text a {
    color: inherit;
    text-decoration: underline;
    text-underline-offset: 3px;
}

.site-header__banner-close {
    position: absolute;
    top: 50%;
    right: var(--gutter);
    display: grid;
    place-items: center;
    width: 32px;
    height: 32px;
    border-radius: 50%;
    color: inherit;
    transform: translateY(-50%);
}

.site-header__banner-close:hover {
    background: color-mix(in srgb, currentColor 12%, transparent);
}

.site-header__banner-close:focus-visible {
    outline: 2px solid currentColor;
    outline-offset: 2px;
}

.site-header__sticky-banners:empty {
    display: none;
}

.site-header__top {
    font-size: 13px;
    line-height: 1.4;
}

.site-header__topbar-inner {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    align-items: center;
    gap: 6px 32px;
    padding-block: 9px;
}

.site-header__topbar-item {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: inherit;
    text-decoration: none;
}

.site-header__topbar-item:hover {
    color: inherit;
}

.site-header__topbar-item svg {
    flex-shrink: 0;
}

a.site-header__topbar-item:hover span,
.site-header__topbar-email {
    text-decoration: underline;
    text-underline-offset: 3px;
}

.site-header__topbar-email:hover {
    text-decoration-thickness: 2px;
}

@media (max-width: 600px) {
    .site-header__top {
        font-size: 12px;
    }

    .site-header__topbar-inner {
        gap: 4px 20px;
    }
}

/* ---------- Nav bar ---------- */

.site-header__bar {
    position: absolute;
    left: 0;
    right: 0;
    background-color: transparent;
}

/* Transitions only once the page has loaded (.is-ready), so it opens in its scrolled or
   unscrolled state without animating into it */
.site-header.is-ready .site-header__bar {
    transition: background-color .6s ease, backdrop-filter .6s ease, -webkit-backdrop-filter .6s ease;
}

/* Solid black when the first section isn't dark (nothing behind it to show through) */
body:not(:is(.header-overlay, :has(.site-main > .is-dark:first-child))) .site-header__bar,
body.header-drawer-open .site-header__bar {
    background-color: var(--black);
}

/* At the top, over a dark first section: a soft black-to-clear fade behind the bar (and
   the hanging logo), so the menu reads on any hero image. It fades out once scrolled. */
.site-header__bar {
    isolation: isolate;
}

.site-header__bar::before {
    content: '';
    position: absolute;
    z-index: -1;
    top: 0;
    left: 0;
    right: 0;
    height: calc(100% + 96px);
    background: linear-gradient(180deg, color-mix(in srgb, var(--black) 65%, transparent), transparent);
    opacity: 0;
    pointer-events: none;
}

.site-header.is-ready .site-header__bar::before {
    transition: opacity .6s ease;
}

body:is(.header-overlay, :has(.site-main > .is-dark:first-child)):not(.header-drawer-open) .site-header:not(.is-scrolled) .site-header__bar::before {
    opacity: 1;
}

/* Scrolled: translucent black, the page blurred behind */
.site-header.is-scrolled .site-header__bar {
    background-color: var(--bar-bg-scrolled);
    -webkit-backdrop-filter: blur(var(--bar-blur));
    backdrop-filter: blur(var(--bar-blur));
}

@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
    .site-header.is-scrolled .site-header__bar,
    .site-header__drawer {
        background-color: var(--black);
    }
}

/* Logo | menu | buttons: the side columns share the leftover space equally, so the
   menu is centred on the bar itself (it slides left only if the buttons need more). */
.site-header__bar-inner {
    display: grid;
    grid-template-columns: minmax(max-content, 1fr) auto minmax(max-content, 1fr);
    align-items: center;
    column-gap: var(--step-7);
    height: var(--bar-height);
}

/* The logo is pinned at the scrolled logo's top edge and hangs down when larger,
   so it shrinks up into the bar. */
.site-header__brand {
    justify-self: start;
    align-self: start;
    display: flex;
    align-items: flex-start;
    height: var(--bar-height);
    padding-top: calc((var(--bar-height) - var(--logo-h-scrolled)) / 2);
}

.site-header__logo {
    display: block;
    line-height: 0;
}

.site-header__logo img {
    width: auto;
    height: var(--logo-h-top-fit, var(--logo-h-top));
    max-width: none;
}

.site-header.is-ready .site-header__logo img {
    transition: height .3s ease;
}

.site-header.is-scrolled .site-header__bar .site-header__logo img,
body:not(:is(.header-overlay, :has(.site-main > .is-dark:first-child))) .site-header__bar .site-header__logo img {
    height: var(--logo-h-scrolled);
}

.site-header__nav {
    justify-self: center;
}

.site-header__menu {
    display: flex;
    align-items: center;
    gap: 4px var(--step-7);
    margin: 0;
    padding: 0;
    list-style: none;
    white-space: nowrap;
}

.site-header__menu > li {
    position: relative;
    margin: 0;
}

.site-header__menu a {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 0;
    color: var(--white);
    font-size: 15px;
    line-height: 1.2;
    text-decoration: none;
    transition: color .2s ease;
}

.site-header__menu a:hover,
.site-header__menu .current-menu-item > a,
.site-header__menu .current-menu-ancestor > a {
    color: var(--tertiary-200);
    /* a soft black glow behind it, so the gold holds up over light parts of a hero photo */
    text-shadow: 0 0 10px color-mix(in srgb, var(--black) 85%, transparent), 0 0 3px color-mix(in srgb, var(--black) 60%, transparent);
}


.site-header__menu a:focus-visible {
    outline: 2px solid var(--tertiary-200);
    outline-offset: 4px;
    border-radius: 2px;
}

/* One level of dropdown */
.site-header__menu .menu-item-has-children > a::after {
    content: '';
    width: 6px;
    height: 6px;
    margin-top: -3px;
    border-right: 1.5px solid currentColor;
    border-bottom: 1.5px solid currentColor;
    transform: rotate(45deg);
}

.site-header__menu .sub-menu {
    position: absolute;
    top: 100%;
    left: 50%;
    min-width: 200px;
    margin: 0;
    padding: 8px 0;
    list-style: none;
    background: var(--black);
    border: 1px solid color-mix(in srgb, var(--neutral-50) 12%, transparent);
    border-radius: 8px;
    opacity: 0;
    visibility: hidden;
    transform: translate(-50%, 6px);
    transition: opacity .2s ease, transform .2s ease, visibility 0s .2s;
}

.site-header__menu li:hover > .sub-menu,
.site-header__menu li:focus-within > .sub-menu {
    opacity: 1;
    visibility: visible;
    transform: translate(-50%, 0);
    transition: opacity .2s ease, transform .2s ease;
}

.site-header__menu .sub-menu li + li {
    margin-top: 0;
}

.site-header__menu .sub-menu a {
    display: block;
    padding: 8px 16px;
}

.site-header__actions {
    justify-self: end;
    display: flex;
    align-items: center;
    gap: var(--step-4);
}

.site-header__buttons {
    display: flex;
    gap: var(--step-4);
}

/* Outline buttons on the dark bar and drawer (e.g. "Staff portal") */
.site-header :is(.site-header__buttons, .site-header__drawer-buttons) > .btn--outline {
    --btn-text: var(--white);
    --btn-text-hover: var(--white);
    --btn-border: rgba(255, 255, 255, .55);
    --btn-border-hover: var(--white);
    --btn-bg-hover: rgba(255, 255, 255, .1);
}

/* Menu button */
.site-header__toggle {
    display: none;
    position: relative;
    width: 40px;
    height: 40px;
    color: var(--white);
}

.site-header__toggle-icon,
.site-header__toggle-icon::before,
.site-header__toggle-icon::after {
    position: absolute;
    left: 50%;
    width: 22px;
    height: 1.5px;
    margin-left: -11px;
    border-radius: 1px;
    background: currentColor;
}

.site-header__toggle-icon {
    top: 50%;
}

.site-header__toggle-icon::before,
.site-header__toggle-icon::after {
    content: '';
    left: 0;
    margin-left: 0;
}

.site-header__toggle-icon::before { top: -7px; }
.site-header__toggle-icon::after { top: 7px; }

.site-header__toggle:focus-visible {
    outline: 2px solid var(--tertiary-200);
    outline-offset: 2px;
    border-radius: 4px;
}

/* Collapsed: links and buttons hidden (still measurable), the menu button shown.
   script.js decides; under 860px without the script, the same happens anyway. */
.site-header.is-collapsed .site-header__bar-inner {
    grid-template-columns: minmax(max-content, 1fr) auto;
    position: relative;
    overflow-x: clip; /* the hidden links don’t widen the page */
}

.site-header.is-collapsed :is(.site-header__nav, .site-header__buttons) {
    position: absolute;
    visibility: hidden;
    pointer-events: none;
}

.site-header.is-collapsed .site-header__toggle {
    display: block;
}

@media (max-width: 860px) {
    .site-header:not(.is-measured) .site-header__bar-inner {
        grid-template-columns: minmax(max-content, 1fr) auto;
    }

    .site-header:not(.is-measured) :is(.site-header__nav, .site-header__buttons) {
        display: none;
    }

    .site-header:not(.is-measured) .site-header__toggle {
        display: block;
    }
}

/* ---------- Mobile menu drawer ---------- */

.site-header__scrim {
    position: fixed;
    inset: 0;
    z-index: 600;
    background: rgba(0, 0, 0, .6);
    opacity: 0;
    transition: opacity .3s ease;
}

.site-header__drawer {
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    z-index: 610;
    display: flex;
    flex-direction: column;
    width: min(400px, 100%);
    /* Bottom: room under the buttons (more on phones with a home bar) */
    padding: var(--step-6) var(--gutter) calc(var(--step-10) + env(safe-area-inset-bottom, 0px));
    overflow-y: auto;
    overscroll-behavior: contain;
    /* Like the nav bar once scrolled, a little lighter as the overlay behind darkens the page */
    background: rgba(0, 0, 0, .6);
    -webkit-backdrop-filter: blur(var(--bar-blur));
    backdrop-filter: blur(var(--bar-blur));
    transform: translateX(100%);
    transition: transform .3s cubic-bezier(.4, 0, .2, 1);
}

.site-header__scrim.is-open { opacity: 1; }
.site-header__drawer.is-open { transform: none; }

.site-header__drawer[hidden],
.site-header__scrim[hidden] {
    display: none;
}

.site-header__drawer-top {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: var(--step-8);
}

.site-header__logo--drawer img {
    height: 40px;
}

.site-header__drawer-close {
    position: relative;
    width: 40px;
    height: 40px;
    color: var(--white);
}

.site-header__drawer-close::before,
.site-header__drawer-close::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 22px;
    height: 1.5px;
    background: currentColor;
    transform: translate(-50%, -50%) rotate(45deg);
}

.site-header__drawer-close::after {
    transform: translate(-50%, -50%) rotate(-45deg);
}

.site-header__drawer-close:focus-visible {
    outline: 2px solid var(--tertiary-200);
    border-radius: 4px;
}

.site-header__drawer-menu,
.site-header__drawer-menu .sub-menu {
    margin: 0;
    padding: 0;
    list-style: none;
}

.site-header__drawer-menu > li {
    margin: 0;
    border-bottom: 1px solid color-mix(in srgb, var(--neutral-50) 15%, transparent);
}

.site-header__drawer-menu a {
    display: block;
    padding: 16px 0;
    color: var(--white);
    font-size: 20px;
    line-height: 1.3;
    text-decoration: none;
}

.site-header__drawer-menu .sub-menu {
    padding: 0 0 12px 16px;
}

.site-header__drawer-menu .sub-menu a {
    padding: 8px 0;
    font-size: 16px;
    opacity: .8;
}

.site-header__drawer-menu a:hover,
.site-header__drawer-menu .current-menu-item > a {
    color: var(--tertiary-200);
}

.site-header__drawer-menu a:focus-visible {
    outline: 2px solid var(--tertiary-200);
    outline-offset: 2px;
}

.site-header__drawer-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--step-4);
    margin-top: auto;
    padding-top: var(--step-8);
}

.site-header__drawer-buttons > a {
    width: 100%;
}

body.header-drawer-open {
    overflow: hidden;
}

@media (prefers-reduced-motion: reduce) {
    .site-header.is-ready .site-header__bar,
    .site-header.is-ready .site-header__logo img,
    .site-header__drawer,
    .site-header__scrim {
        transition: none;
    }
}