/* Site navigation: one frosted-glass capsule. Logo pill at the start, plain links in the middle,
   the language toggle at the end. Phones swap the links for a menu.

   Motion:
   - links: one highlight pill glides to the hovered link (200ms, strong ease-out); it appears
     in place on first hover and fades when the pointer leaves, so it never flies in from a
     stale position. Hover only on fine pointers.
   - logo: yellow brightens; pressables scale to .97.
   - phone menu: panel scales in from its button (origin-aware) and leaves faster than it came. */

.site-nav {
  --nav-pad: 8px;
  --nav-item-h: var(--tap-min);
  --glass: rgba(24, 26, 31, 0.55);
  --glass-edge: rgba(255, 255, 255, 0.14);
  --nav-text: rgba(255, 255, 255, 0.86);
  position: fixed; z-index: 50;
  top: max(16px, env(safe-area-inset-top));
  left: 50%; translate: -50% 0;
  display: flex; align-items: center; gap: 4px;
  padding: var(--nav-pad);
  border-radius: 999px;
  background: var(--glass);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
          backdrop-filter: blur(18px) saturate(160%);
  box-shadow:
    inset 0 0 0 1px var(--glass-edge),
    inset 0 1px 0 rgba(255, 255, 255, 0.08),
    0 18px 40px -12px rgba(0, 0, 0, 0.55);
  font-family: var(--font);
}
/* no backdrop blur support: fall back to a solid bar so the links stay readable */
@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .site-nav { --glass: rgba(24, 26, 31, 0.94); }
}

/* Logo: the H10 wordmark (traced from the official avatar) on a yellow pill */
.site-nav__logo {
  flex: none; height: var(--nav-item-h);
  display: flex; align-items: center;
  padding-inline: 18px;
  border-radius: 999px;
  background: var(--h10-yellow); color: var(--h10-ink);
  text-decoration: none;
  transition: background-color 150ms ease, transform 160ms var(--ease-out);
  -webkit-tap-highlight-color: transparent;
}
.site-nav__logo .h10-wordmark { height: 17px; width: auto; }
.site-nav__logo:active { transform: scale(0.97); }

/* Links */
.site-nav__links { position: relative; margin-inline: 12px; }
.site-nav__list { position: relative; z-index: 1; display: flex; align-items: center; margin: 0; padding: 0; list-style: none; }
.site-nav__link {
  display: flex; align-items: center;
  height: calc(var(--nav-item-h) - 8px);
  padding-inline: 18px;
  border-radius: 999px;
  color: var(--nav-text); text-decoration: none; white-space: nowrap;
  font-size: 16px; font-weight: 600;
  transition: color 150ms ease, transform 160ms var(--ease-out);
}
.site-nav__link[aria-current="page"] { color: #FFFFFF; }
.site-nav__link:active { transform: scale(0.97); }
.site-nav__glide {
  position: absolute; z-index: 0; top: 50%; left: 0;
  height: calc(var(--nav-item-h) - 8px); margin-top: calc((var(--nav-item-h) - 8px) / -2); width: 0;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.1);
  opacity: 0; pointer-events: none;
  transition: opacity 150ms ease;
}
.site-nav__glide.is-gliding {
  transition: opacity 150ms ease, transform 200ms var(--ease-out), width 200ms var(--ease-out);
}

/* Menu button (phones) */
.site-nav__menu {
  display: none; flex: none;
  width: var(--nav-item-h); aspect-ratio: 1; padding: 0;
  place-items: center;
  border: 0; border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  cursor: pointer; -webkit-tap-highlight-color: transparent;
  transition: background-color 150ms ease, transform 160ms var(--ease-out);
}
.site-nav__menu:active { transform: scale(0.97); }
.site-nav__burger { position: relative; width: 18px; height: 12px; }
.site-nav__burger::before, .site-nav__burger::after {
  content: ""; position: absolute; left: 0; width: 18px; height: 2px; border-radius: 1px;
  background: #FFFFFF;
  transition: transform 200ms var(--ease-out);
}
.site-nav__burger::before { top: 0; }
.site-nav__burger::after { bottom: 0; }
.site-nav__menu[aria-expanded="true"] .site-nav__burger::before { transform: translateY(5px) rotate(45deg); }
.site-nav__menu[aria-expanded="true"] .site-nav__burger::after { transform: translateY(-5px) rotate(-45deg); }

/* Phone menu panel. A sibling of the bar, not a child: a backdrop-filter inside another one
   only blurs the bar, not the page behind it. */
.site-nav-panel {
  position: fixed; z-index: 49;
  top: calc(max(16px, env(safe-area-inset-top)) + var(--tap-min) + 16px + 10px);
  left: 50%; translate: -50% 0;
  width: min(360px, calc(100vw - 32px));
  padding: 8px;
  border-radius: 24px;
  background: rgba(24, 26, 31, 0.72);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
          backdrop-filter: blur(18px) saturate(160%);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.14), 0 18px 40px -12px rgba(0, 0, 0, 0.55);
  transform-origin: top left;              /* the menu button sits at the end: left in RTL */
  opacity: 0; transform: translateY(-6px) scale(0.96); visibility: hidden;
  transition: opacity 150ms ease, transform 150ms var(--ease-out), visibility 0s linear 150ms;
}
.site-nav-panel:dir(ltr) { transform-origin: top right; }
.site-nav-panel[data-open] {
  opacity: 1; transform: none; visibility: visible;
  transition: opacity 200ms ease, transform 200ms var(--ease-out), visibility 0s;
}
.site-nav-panel ul { display: grid; margin: 0; padding: 0; list-style: none; }
.site-nav-panel a {
  display: flex; align-items: center; min-height: 48px; padding-inline: 16px;
  border-radius: 16px;
  color: #FFFFFF; text-decoration: none; font: 600 16px/1.4 var(--font);
}
.site-nav-panel a:active { background: rgba(255, 255, 255, 0.1); }

.site-nav :focus-visible, .site-nav-panel :focus-visible { outline: 2px solid var(--h10-yellow); outline-offset: 2px; }

@media (hover: hover) and (pointer: fine) {
  .site-nav__logo:hover { background: var(--h10-yellow-hover); }
  .site-nav__link:hover { color: #FFFFFF; }
  .site-nav__menu:hover { background: rgba(255, 255, 255, 0.14); }
  .site-nav-panel a:hover { background: rgba(255, 255, 255, 0.1); }
}

@media (max-width: 760px) {
  .site-nav { --nav-pad: 6px; }
  .site-nav__links { display: none; }
  .site-nav__menu { display: grid; }
  .site-nav-panel { top: calc(max(16px, env(safe-area-inset-top)) + var(--tap-min) + 12px + 10px); }
}
@media (min-width: 761px) {
  .site-nav-panel { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  .site-nav__glide.is-gliding { transition: opacity 150ms ease; }
  .site-nav-panel, .site-nav-panel[data-open] { transform: none; }
  .site-nav__burger::before, .site-nav__burger::after { transition: none; }
}

/* Language toggle: the last item in the bar. Two options in a darker inset pill, the current one
   filled yellow; the other is a link to the same page in that language. */
.lang-toggle {
  flex: none;
  display: flex; gap: 2px; padding: 4px;
  border-radius: 999px;
  background: rgba(0, 0, 0, 0.28);
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.08);
}
.lang-toggle__opt {
  display: grid; place-items: center;
  min-width: 40px; height: calc(var(--nav-item-h) - 8px); padding: 0 10px;
  border-radius: 999px;
  color: rgba(255, 255, 255, 0.78); text-decoration: none;
  font: 600 14px/1 var(--font-sf); letter-spacing: 0.02em;
  transition: background-color 150ms ease, color 150ms ease, transform 160ms var(--ease-out);
}
.lang-toggle__opt[lang="ar"] { font-family: var(--font); font-size: 15px; }
.lang-toggle__opt[aria-current="page"] { background: var(--h10-yellow); color: var(--h10-ink); }
a.lang-toggle__opt:active { transform: scale(0.95); }
@media (hover: hover) and (pointer: fine) {
  a.lang-toggle__opt:hover { background: rgba(255, 255, 255, 0.12); color: #FFFFFF; }
}
@media (max-width: 760px) {
  .lang-toggle { margin-inline-start: auto; padding: 3px; }
  .lang-toggle__opt { min-width: 38px; height: calc(var(--nav-item-h) - 6px); font-size: 13px; }
}
@media (prefers-reduced-motion: reduce) {
  .lang-toggle__opt { transition: none; }
}