/* ==========================================================================
   FEEDER — HEADER / NAV
   ========================================================================== */

.site-header {
  position: fixed;
  inset-inline: 0;
  top: 0;
  z-index: 100;
  height: var(--header-h);
  display: flex;
  align-items: center;
  transition: background var(--dur-fast) ease, border-color var(--dur-fast) ease, height var(--dur-fast) ease;
  border-bottom: 1px solid transparent;
}

.site-header.is-scrolled {
  background: rgba(3, 5, 10, 0.72);
  backdrop-filter: blur(16px) saturate(140%);
  -webkit-backdrop-filter: blur(16px) saturate(140%);
  border-bottom-color: var(--border-subtle);
  height: 72px;
}

.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-6);
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  font-family: var(--font-display);
  font-weight: 700;
  font-size: var(--fs-lg);
  color: var(--text-primary);
  flex-shrink: 0;
}

.brand-mark {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  display: grid;
  place-items: center;
  background: var(--accent-gradient);
  color: var(--bg-950);
}

.brand-mark svg {
  width: 20px;
  height: 20px;
}

.main-nav {
  display: flex;
  align-items: center;
  gap: var(--sp-7);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--sp-6);
}

.nav-links a {
  font-size: var(--fs-sm);
  font-weight: 500;
  color: var(--text-secondary);
  position: relative;
  padding-block: var(--sp-2);
  transition: color var(--dur-fast) ease;
}

.nav-links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background: var(--accent-cyan);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--dur-fast) ease;
}

html[dir="rtl"] .nav-links a::after {
  transform-origin: right;
}

.nav-links a:hover {
  color: var(--text-primary);
}

.nav-links a:hover::after {
  transform: scaleX(1);
}

.header-actions {
  display: flex;
  align-items: center;
  gap: var(--sp-4);
}

.header-actions--mobile-only-lang {
  display: none;
}

/* ---------- Language switcher ---------- */
.lang-switch {
  position: relative;
}

.lang-switch-btn {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--radius-pill);
  border: 1px solid var(--border-subtle);
  font-size: var(--fs-xs);
  font-weight: 600;
  letter-spacing: var(--ls-wide);
  text-transform: uppercase;
  color: var(--text-secondary);
}

.lang-switch-btn:hover {
  color: var(--text-primary);
  border-color: var(--border-strong);
}

.lang-switch-btn svg {
  width: 14px;
  height: 14px;
  transition: transform var(--dur-fast) ease;
}

.lang-switch.is-open .lang-switch-btn svg {
  transform: rotate(180deg);
}

.lang-menu {
  position: absolute;
  top: calc(100% + var(--sp-3));
  inset-inline-end: 0;
  min-width: 168px;
  padding: var(--sp-2);
  border-radius: var(--radius-md);
  background: var(--surface-glass-strong);
  border: 1px solid var(--border-subtle);
  backdrop-filter: blur(20px);
  box-shadow: var(--shadow-md);
  opacity: 0;
  transform: translateY(-8px);
  pointer-events: none;
  transition: opacity var(--dur-fast) ease, transform var(--dur-fast) ease;
}

.lang-switch.is-open .lang-menu {
  opacity: 1;
  transform: translateY(0);
  pointer-events: auto;
}

.lang-menu button {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--sp-3) var(--sp-3);
  border-radius: var(--radius-sm);
  font-size: var(--fs-sm);
  color: var(--text-secondary);
  text-align: start;
}

.lang-menu button:hover {
  background: var(--surface-2);
  color: var(--text-primary);
}

.lang-menu button[aria-current="true"] {
  color: var(--accent-cyan-strong);
}

/* ---------- Mobile toggle ---------- */
.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  border-radius: 50%;
  border: 1px solid var(--border-subtle);
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
}

.nav-toggle span {
  width: 16px;
  height: 1.5px;
  background: var(--text-primary);
  transition: transform var(--dur-fast) ease, opacity var(--dur-fast) ease;
}

/* ---------- Mobile drawer ---------- */
@media (max-width: 960px) {
  .nav-toggle {
    display: inline-flex;
  }

  .main-nav {
    position: fixed;
    inset: 0;
    top: 0;
    flex-direction: column;
    justify-content: center;
    align-items: stretch;
    padding: var(--sp-9) var(--sp-6);
    background: var(--bg-950);
    gap: var(--sp-9);
    transform: translateY(-100%);
    transition: transform var(--dur-normal) cubic-bezier(0.65, 0, 0.35, 1);
    z-index: 90;
  }

  .main-nav.is-open {
    transform: translateY(0);
  }

  .nav-links {
    flex-direction: column;
    align-items: flex-start;
    gap: var(--sp-6);
  }

  .nav-links a {
    font-size: var(--fs-xl);
    font-family: var(--font-display);
  }

  .header-actions {
    flex-wrap: wrap;
  }

  .header-actions--mobile-only-lang {
    display: flex;
  }

  .lang-switch--desktop {
    display: none;
  }
}