/* Lightpeak — Header & Navigation */

/* ─────────────────────────────────────────────────────────────
   HEADER  Sticky header with nav
   Mobile-first: simple horizontal nav, no dropdowns yet
   ───────────────────────────────────────────────────────────── */

#header {
  background: var(--lp-bg);
  position: relative;
  top: 0;
  z-index: var(--z-index-sticky);
}

body.header-fixed #header {
  position: sticky;
}

.header__scroll-indicator {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--color-border-light);
  overflow: hidden;
}

.header__scroll-line {
  height: 100%;
  width: 0%;
  background: var(--color-brand-gradient);
  transition: width 50ms linear;
}

.navbar {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-scale-2);
  padding-block: var(--space-scale-2);
}

.navbar-section {
  display: flex;
  align-items: center;
  gap: var(--space-scale-3);
}

.desktop-menu {
  margin-left: auto;
  min-width: 0;
  justify-content: flex-end;
}

.navbar > .logo {
  flex: 0 1 148px;
  min-width: 80px;
}

.navbar > .logo a,
.navbar > .logo img {
  width: 100%;
  height: auto;
}

.nav-cta {
  min-width: 100px;
  padding: var(--space-scale-2) var(--space-scale-3);
  font-size: var(--font-size-small);
  overflow-wrap: anywhere;
}

.logo {
  display: flex;
  align-items: center;
}

.logo img {
  max-height: 40px;
  width: auto;
}

.logo__dark { display: none; }
.logo__light { display: block; }

:root[data-theme='dark'] .logo__light { display: none; }
:root[data-theme='dark'] .logo__dark { display: block; }

#footer .logo__light,
.mobile-menu .logo__light { display: none; }
#footer .logo__dark,
.mobile-menu .logo__dark { display: block; }

.logo.text-logo {
  font-family: var(--font-family-semibold);
  font-size: var(--font-size-heading-h3);
  font-weight: var(--font-weight-semibold);
  color: var(--lp-fg);
}

/* Navigation disclosures: native buttons, page links inside each panel. */
.nav-desktop { display: none; }
.nav-hamburger {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  flex-shrink: 0;
  padding: var(--space-scale-2);
  border: none;
  background: none;
  color: var(--lp-fg);
  cursor: pointer;
}
.nav-hamburger-line {
  width: 24px;
  height: 2px;
  border-top: 2px solid currentColor;
}
.nav-chevron {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  border-right: 1.5px solid currentColor;
  border-bottom: 1.5px solid currentColor;
  transform: rotate(45deg);
  transition: transform var(--motion-duration-fast) var(--motion-easing);
}
[aria-expanded="true"] > .nav-chevron { transform: rotate(225deg); }
.nav-dropdown[hidden], .mobile-nav-children[hidden] { display: none; }

.mobile-menu-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  opacity: 0;
  pointer-events: none;
  z-index: var(--z-index-offcanvas);
  transition: opacity var(--motion-duration-base) var(--motion-easing);
}
.mobile-menu-overlay.is-open { opacity: 1; pointer-events: auto; }
.mobile-menu {
  position: fixed;
  top: 0;
  right: 0;
  width: min(100%, 420px);
  height: 100vh;
  height: 100dvh;
  background: var(--color-surface-dark);
  transform: translateX(100%);
  visibility: hidden;
  z-index: calc(var(--z-index-offcanvas) + 1);
  display: flex;
  flex-direction: column;
  transition: transform var(--motion-duration-base) var(--motion-easing),
              visibility var(--motion-duration-base);
  overflow-y: auto;
  overscroll-behavior-y: contain;
}
.mobile-menu.is-open { transform: translateX(0); visibility: visible; }
.mobile-menu {
  --color-text-link: var(--color-brand-blue);
  --lp-link: var(--color-text-link);
}
.mobile-menu__header {
  position: sticky;
  top: 0;
  z-index: 1;
  display: flex;
  flex-shrink: 0;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-scale-4) var(--space-scale-6);
  border-bottom: 1px solid var(--color-border-dark);
  background: var(--color-surface-dark);
}
.mobile-menu__close {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border: none;
  background: none;
  cursor: pointer;
  color: var(--color-text-on-dark);
}
.mobile-menu__close svg { width: 20px; height: 20px; }
.mobile-menu__nav { flex: 1; padding: var(--space-scale-4) var(--space-scale-6); }
.mobile-nav-list, .mobile-nav-children, .nav-entry__children { list-style: none; margin: 0; padding: 0; }
.mobile-nav-item { border-bottom: 1px solid var(--color-border-dark); }
.mobile-nav-item > a, .mobile-nav-trigger {
  display: flex;
  width: 100%;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-scale-4);
  padding: var(--space-scale-4) 0;
  border: none;
  background: none;
  color: var(--color-text-on-dark);
  font-family: inherit;
  font-size: var(--font-size-body);
  font-weight: var(--font-weight-semibold);
  text-align: left;
  text-decoration: none;
  cursor: pointer;
}
.mobile-nav-item.active > a,
.mobile-nav-item.active > .mobile-nav-trigger,
.mobile-nav-trigger[aria-expanded="true"] { color: var(--color-text-link); }
.mobile-nav-children { padding-bottom: var(--space-scale-4); }
.mobile-nav-children a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-scale-3);
  min-height: 44px;
  padding: var(--space-scale-3);
  border-radius: var(--radius-scale-sm);
  color: var(--color-text-secondary-inverse);
  font-size: var(--font-size-small);
  text-decoration: none;
  text-align: left;
}
.mobile-nav-children a:hover, .mobile-nav-children a:focus-visible,
.mobile-nav-children a[aria-current="page"] {
  color: var(--color-text-on-dark);
  background: var(--color-navy-card);
}
.mobile-nav-children .mobile-nav-overview { color: var(--color-text-accent); }
.mobile-nav-children .nav-entry__arrow { display: none; }
.nav-entry__children { padding-inline-start: var(--space-scale-4); }
.mobile-menu__actions {
  display: flex;
  flex-direction: column;
  gap: var(--space-scale-4);
  padding-block: var(--space-scale-6);
}
.mobile-menu__cta { text-align: center; }
.mobile-menu .langswitch-link { color: var(--color-text-secondary-inverse); }
.mobile-menu .langswitch-link.is-active { color: var(--color-text-link); }

.langswitch {
  display: flex;
  align-items: center;
  gap: var(--space-scale-1);
}

.langswitch-link {
  font-size: var(--font-size-caption);
  font-weight: var(--font-weight-semibold);
  color: var(--color-text-secondary);
  text-decoration: none;
  letter-spacing: 0.05em;
}

.langswitch-link.is-active {
  color: var(--color-text-link);
}

.langswitch-sep {
  color: var(--color-text-secondary);
  opacity: 0.4;
  font-size: var(--font-size-caption);
}

body.mobile-menu-open { overflow: hidden; }

.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: 1px solid var(--lp-border);
  border-radius: var(--radius-scale-sm);
  background: none;
  cursor: pointer;
  color: var(--lp-fg);
  flex-shrink: 0;
}

.theme-toggle:hover {
  border-color: var(--color-brand-primary);
  color: var(--color-text-accent);
}

.theme-toggle__sun { display: block; width: 16px; height: 16px; }
.theme-toggle__moon { display: none; width: 16px; height: 16px; }

:root[data-theme='dark'] .theme-toggle__sun { display: none; }
:root[data-theme='dark'] .theme-toggle__moon { display: block; }
.theme-toggle--footer {
  width: 44px;
  height: 44px;
  border-radius: var(--radius-scale-md);
  border-color: var(--color-navy-border);
  color: var(--color-text-on-dark);
  opacity: 0.85;
  transition: opacity var(--motion-duration-fast) ease, border-color var(--motion-duration-fast) ease;
}

.theme-toggle--footer:hover {
  opacity: 1;
  border-color: var(--color-brand-primary);
}

/* Two-column panels share one alignment beneath the main navigation. */
.navigation, .navigation ul { list-style: none; margin: 0; padding: 0; }
@media (min-width: 1024px) {
  .nav-hamburger { display: none; }
  .nav-desktop { display: flex; align-items: center; gap: var(--space-scale-4); }
  .navigation { display: flex; align-items: center; gap: var(--space-scale-4); }
  .nav-item > a, .nav-trigger {
    display: flex;
    align-items: center;
    gap: var(--space-scale-2);
    min-height: 44px;
    padding: var(--space-scale-2) 0;
    border: none;
    background: none;
    color: var(--lp-fg);
    font-family: inherit;
    font-size: var(--font-size-small);
    font-weight: var(--font-weight-semibold);
    text-decoration: none;
    cursor: pointer;
    white-space: nowrap;
  }
  .nav-item.active > a, .nav-item.active > .nav-trigger,
  .nav-trigger[aria-expanded="true"] { color: var(--color-text-link); }
  .nav-dropdown {
    position: absolute;
    top: 100%;
    right: 0;
    width: min(760px, 100%);
    max-height: calc(100vh - var(--space-scale-24));
    max-height: calc(100dvh - var(--space-scale-24));
    overflow-y: auto;
    overscroll-behavior-y: contain;
    background: var(--color-surface-primary);
    border: 1px solid var(--color-border-light);
    border-radius: var(--radius-scale-lg);
    box-shadow: var(--shadow-level-dropdown);
    padding: var(--space-scale-6);
    z-index: var(--z-index-dropdown);
    text-align: left;
  }
  .nav-dropdown__header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-scale-4);
    padding-bottom: var(--space-scale-4);
    margin-bottom: var(--space-scale-3);
    border-bottom: 1px solid var(--color-border-light);
  }
  .nav-dropdown__title {
    font-size: var(--font-size-body);
    font-weight: var(--font-weight-semibold);
    color: var(--lp-fg);
  }
  .nav-dropdown__overview {
    display: inline-flex;
    align-items: center;
    gap: var(--space-scale-3);
    color: var(--lp-fg);
    font-size: var(--font-size-small);
    text-decoration: none;
  }
  .nav-dropdown__overview:hover { text-decoration: underline; text-underline-offset: 4px; }
  .navigation .nav-dropdown__list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: var(--space-scale-2) var(--space-scale-4);
  }
  .nav-entry {
    display: flex;
    height: 100%;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-scale-3);
    padding: var(--space-scale-3);
    border-radius: var(--radius-scale-md);
    color: var(--lp-fg);
    text-decoration: none;
    transition: background var(--motion-duration-fast) var(--motion-easing);
  }
  .nav-entry:hover, .nav-entry:focus-visible, .nav-entry[aria-current="page"] {
    background: var(--color-surface-secondary);
  }
  .nav-entry__copy { display: flex; flex-direction: column; gap: var(--space-scale-1); }
  .nav-item__label { font-size: var(--font-size-small); line-height: var(--line-height-small); font-weight: var(--font-weight-semibold); }
  .nav-item__desc { font-size: var(--font-size-caption); line-height: var(--line-height-caption); color: var(--color-text-secondary); }
  .nav-entry__arrow { flex-shrink: 0; color: var(--color-text-secondary); }
  .nav-entry:hover .nav-entry__arrow,
  .nav-entry:focus-visible .nav-entry__arrow { color: var(--color-text-accent); }
  .nav-actions { display: flex; align-items: center; gap: var(--space-scale-4); }
  .nav-cta { font-size: var(--font-size-small); padding: var(--space-scale-2) var(--space-scale-4); white-space: nowrap; }
}
@media (min-width: 1440px) {
  .nav-desktop, .navigation { gap: var(--space-scale-6); }
}
@media (prefers-reduced-motion: reduce) {
  .mobile-menu, .mobile-menu-overlay, .nav-chevron, .nav-entry { transition: none; }
}