/* QERIS shared chrome: header, primary navigation, language switch and page transitions.
   Used unchanged by site pages, registry pages, institution pages and AccessTwin. */

html { scrollbar-gutter: stable; }

/* ---------- Page transitions ----------
   One behaviour for every same-origin navigation (pages and languages): the outgoing
   page is removed at once, the incoming page fades in briefly, and the header is a
   separate, unanimated layer so it never moves or blinks. The canvas carries the page
   colour, so there is no white frame. */
@view-transition {
  navigation: auto;
}

::view-transition-old(root) {
  animation: none;
  opacity: 0;
}

::view-transition-new(root) {
  animation: qeris-page-in var(--dur-page) var(--ease-out) both;
}

@keyframes qeris-page-in {
  from { opacity: 0; }
  to { opacity: 1; }
}

.site-header { view-transition-name: site-header; }

::view-transition-group(site-header) { animation: none; }
::view-transition-old(site-header) { display: none; }
::view-transition-new(site-header) { animation: none; }

@media (prefers-reduced-motion: reduce) {
  ::view-transition-new(root),
  ::view-transition-old(root) {
    animation: none;
  }
}

body::before {
  content: none !important;
  display: none !important;
}

html[data-qeris-localizing] body { visibility: visible !important; }

/* ---------- Header ---------- */

.site-header {
  position: sticky;
  top: 0;
  z-index: var(--z-header);
  height: var(--header-height);
  background: rgba(248, 246, 240, 0.94);
  -webkit-backdrop-filter: blur(16px);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(17, 19, 24, 0.1);
  isolation: isolate;
}

.nav {
  display: flex;
  align-items: center;
  gap: 20px;
  height: var(--header-height);
}

.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  min-width: 0;
  min-height: var(--tap);
  margin-inline-end: auto;
  color: var(--text);
  text-decoration: none;
}

.brand-mark {
  position: relative;
  flex: 0 0 auto;
  width: 30px;
  height: 30px;
  border: 1px solid var(--signal);
  border-radius: 6px;
  background: var(--signal);
}

.brand-mark::before,
.brand-mark::after {
  content: "";
  position: absolute;
  background: #fff;
}

.brand-mark::before { width: 16px; height: 2px; top: 14px; left: 6px; }

.brand-mark::after {
  width: 4px;
  height: 4px;
  top: 13px;
  left: 13px;
  border-radius: 50%;
  box-shadow: -7px 0 0 rgba(255, 255, 255, 0.72), 7px 0 0 rgba(255, 255, 255, 0.72);
}

.brand > span:last-child { min-width: 0; }

.brand strong {
  display: block;
  font-size: 0.98rem;
  line-height: 1.15;
  letter-spacing: var(--ls-brand);
}

.brand small {
  display: block;
  max-width: 260px;
  margin-top: 1px;
  overflow: hidden;
  color: var(--muted);
  font-size: var(--fs-meta);
  line-height: 1.25;
  white-space: nowrap;
  text-overflow: ellipsis;
}

/* Primary navigation */
.site-nav { display: flex; align-items: center; }

.nav-links {
  display: flex;
  align-items: center;
  gap: 4px;
}

.nav-links a {
  position: relative;
  display: inline-flex;
  align-items: center;
  min-height: var(--tap);
  padding: 0 9px;
  border-radius: var(--radius-control);
  color: var(--muted);
  font-size: var(--fs-small);
  font-weight: var(--fw-strong);
  white-space: nowrap;
  text-decoration: none;
}

.nav-links a:hover,
.nav-links a:focus-visible { color: var(--signal-deep); }

.nav-links a[aria-current] { color: var(--text); }

.nav-links a[aria-current]::after {
  content: "";
  position: absolute;
  inset-inline: 9px;
  bottom: 8px;
  height: 2px;
  border-radius: var(--radius-pill);
  background: var(--signal);
}

/* Menu toggle (small screens) */
.nav-toggle {
  display: none;
  align-items: center;
  gap: 8px;
  min-height: var(--tap);
  min-width: var(--tap);
  padding: 0 12px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-control);
  background: rgba(255, 255, 255, 0.72);
  color: var(--text);
  font: inherit;
  font-size: var(--fs-small);
  font-weight: var(--fw-meta);
  cursor: pointer;
}

.nav-toggle:hover { border-color: var(--signal); }

.nav-toggle__bars,
.nav-toggle__bars::before,
.nav-toggle__bars::after {
  display: block;
  width: 16px;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform var(--dur-fast) ease, opacity var(--dur-fast) ease;
}

.nav-toggle__bars { position: relative; }
.nav-toggle__bars::before,
.nav-toggle__bars::after { content: ""; position: absolute; inset-inline-start: 0; }
.nav-toggle__bars::before { top: -5px; }
.nav-toggle__bars::after { top: 5px; }

.nav-toggle[aria-expanded="true"] .nav-toggle__bars { background: transparent; }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::before { transform: translateY(5px) rotate(45deg); }
.nav-toggle[aria-expanded="true"] .nav-toggle__bars::after { transform: translateY(-5px) rotate(-45deg); }

/* ---------- Language switch ---------- */

.lang-switch {
  position: relative;
  flex: 0 0 auto;
}

.lang-switch__btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  min-width: 84px;
  min-height: var(--tap);
  padding: 0 11px;
  border: 1px solid var(--line-strong);
  border-radius: var(--radius-control);
  background: var(--panel);
  color: var(--text);
  font: inherit;
  font-size: var(--fs-small);
  font-weight: var(--fw-meta);
  line-height: 1;
  cursor: pointer;
  transition: border-color var(--dur-fast) ease, box-shadow var(--dur-fast) ease;
}

.lang-switch__btn:hover,
.lang-switch__btn[aria-expanded="true"] {
  border-color: var(--signal);
  box-shadow: 0 0 0 3px var(--signal-soft);
}

.lang-switch__btn svg {
  width: 16px;
  height: 16px;
  flex: 0 0 auto;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.lang-switch__globe { color: var(--signal-deep); }
.lang-switch__code { letter-spacing: 0.04em; }
.lang-switch__chev { transition: transform var(--dur-fast) ease; }
.lang-switch__btn[aria-expanded="true"] .lang-switch__chev { transform: rotate(180deg); }

.lang-switch__menu {
  position: absolute;
  inset-inline-end: 0;
  top: calc(100% + 8px);
  z-index: var(--z-menu);
  min-width: 196px;
  margin: 0;
  padding: 6px;
  list-style: none;
  border: var(--border-strong);
  border-radius: var(--radius-card);
  background: var(--panel);
  box-shadow: var(--shadow-menu);
}

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

.lang-switch__menu a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: var(--tap);
  padding: 0 12px;
  border-radius: var(--radius-control);
  color: var(--text);
  font-size: var(--fs-body);
  font-weight: 550;
  text-decoration: none;
  white-space: nowrap;
}

.lang-switch__menu a:hover,
.lang-switch__menu a:focus-visible { background: var(--signal-soft); color: var(--signal-deep); }

.lang-switch__menu a[aria-current] { font-weight: var(--fw-meta); }

.lang-switch__tag {
  color: var(--muted);
  font-family: var(--font-sans);
  font-size: var(--fs-meta);
  font-weight: var(--fw-meta);
  letter-spacing: 0.06em;
}

.lang-switch__menu a[aria-current] .lang-switch__tag::before {
  content: "✓";
  margin-inline-end: 6px;
  color: var(--signal);
}

/* ---------- Small screens: one compact row, menu panel below the header ---------- */

@media (max-width: 1099px) {
  .nav { gap: 10px; }

  .nav-toggle { display: inline-flex; }

  .nav-links {
    position: absolute;
    inset-inline: calc(-1 * var(--page-padding));
    top: var(--header-height);
    z-index: var(--z-menu);
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    max-height: calc(100vh - var(--header-height));
    max-height: calc(100dvh - var(--header-height));
    overflow-y: auto;
    padding: 8px var(--page-padding) 16px;
    border-bottom: 1px solid rgba(17, 19, 24, 0.12);
    background: #f8f6f0;
    box-shadow: var(--shadow-menu);
  }

  .site-nav[data-open] .nav-links { display: flex; }

  .nav-links a {
    min-height: 48px;
    padding: 0 12px;
    font-size: var(--fs-body);
    color: var(--text);
  }

  .nav-links a[aria-current] { background: var(--signal-soft); }
  .nav-links a[aria-current]::after { inset-inline: 0 auto; top: 12px; bottom: 12px; width: 3px; height: auto; }
}

@media (max-width: 599px) {
  .brand small { display: none; }
  .lang-switch__btn { min-width: 76px; padding: 0 9px; gap: 5px; }
  .nav-toggle { padding: 0 10px; }
}

@media (max-width: 359px) {
  .nav-toggle__label { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  .nav-toggle__bars,
  .nav-toggle__bars::before,
  .nav-toggle__bars::after,
  .lang-switch__chev { transition: none; }
}