/* ==========================================================================
   navbar.css — Sticky glass navigation + mobile drawer
   Levii Portal · Layout Base / Phase 2
   ========================================================================== */

.site-nav {
  position: sticky;
  top: 0;
  z-index: var(--z-nav);
  width: 100%;
}

.site-nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  height: var(--nav-height);
  margin-block: 0.6rem;
  padding-inline: var(--space-md);
  border-radius: var(--radius-pill);
  background: var(--nav-bg);
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(180%);
  backdrop-filter: blur(var(--glass-blur)) saturate(180%);
  border: 1px solid var(--glass-border);
  transition: box-shadow var(--dur-base) var(--ease-out), background var(--dur-base) var(--ease-out);
}

/* Elevated shadow once the page is scrolled (toggled in navigation.js). */
.site-nav.is-scrolled .site-nav__inner {
  box-shadow: var(--shadow-lg);
}

/* ---- Brand ------------------------------------------------------------ */
.nav-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  font-family: var(--font-display);
  font-weight: 800;
  font-size: var(--text-lg);
  letter-spacing: -0.02em;
  color: var(--text);
}
.nav-brand:hover {
  color: var(--text);
}
.nav-brand__mark {
  height: 32px;
  width: auto; /* wordmark logo — keep intrinsic 2.36:1 ratio */
  flex: none;
}

/* ---- Menu (desktop: links + actions inline) -------------------------- */
.nav-menu {
  display: flex;
  align-items: center;
  gap: var(--space-md);
}

/* ---- Primary links --------------------------------------------------- */
.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-2xs);
  list-style: none;
}
.nav-links a {
  display: inline-block;
  padding: 0.5rem 0.85rem;
  border-radius: var(--radius-pill);
  color: var(--text-secondary);
  font-size: var(--text-sm);
  font-weight: 550;
  transition: color var(--dur-fast) var(--ease-out), background var(--dur-fast) var(--ease-out);
}
.nav-links a:hover,
.nav-links a[aria-current='page'] {
  color: var(--text);
  background: var(--surface-2);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-2xs);
}

/* ---- Theme toggle ----------------------------------------------------- */
.theme-toggle {
  display: inline-grid;
  place-items: center;
  width: 40px;
  height: 40px;
  border-radius: var(--radius-pill);
  color: var(--text-secondary);
  border: 1px solid transparent;
  transition: background var(--dur-fast) var(--ease-out), color var(--dur-fast) var(--ease-out);
}
.theme-toggle:hover {
  background: var(--surface-2);
  color: var(--text);
}
.theme-toggle svg {
  width: 20px;
  height: 20px;
}
.theme-toggle .icon-sun {
  display: none;
}
[data-theme='dark'] .theme-toggle .icon-sun {
  display: block;
}
[data-theme='dark'] .theme-toggle .icon-moon {
  display: none;
}

/* ---- Mobile hamburger ------------------------------------------------- */
.nav-burger {
  display: none;
  width: 42px;
  height: 42px;
  border-radius: var(--radius-pill);
  place-items: center;
  color: var(--text);
}
.nav-burger span,
.nav-burger span::before,
.nav-burger span::after {
  content: '';
  display: block;
  width: 20px;
  height: 2px;
  background: currentColor;
  border-radius: 2px;
  transition: transform var(--dur-base) var(--ease-out), opacity var(--dur-fast) var(--ease-out);
}
.nav-burger span::before {
  transform: translateY(-6px);
}
.nav-burger span::after {
  transform: translateY(4px); /* offset from the ::before flow */
}
.nav-burger[aria-expanded='true'] span {
  background: transparent;
}
.nav-burger[aria-expanded='true'] span::before {
  transform: translateY(0) rotate(45deg);
}
.nav-burger[aria-expanded='true'] span::after {
  transform: translateY(-2px) rotate(-45deg);
}

/* ---- Responsive: drawer ---------------------------------------------- */
@media (max-width: 900px) {
  .nav-burger {
    display: grid;
  }
  .nav-menu {
    position: fixed;
    inset: calc(var(--nav-height) + 1.2rem) var(--gutter) auto var(--gutter);
    flex-direction: column;
    align-items: stretch;
    gap: var(--space-xs);
    padding: var(--space-md);
    border-radius: var(--radius-xl);
    /* Near-opaque so hero content never bleeds through the open drawer. */
    background: color-mix(in srgb, var(--bg-elevated) 95%, transparent);
    -webkit-backdrop-filter: blur(24px) saturate(180%);
    backdrop-filter: blur(24px) saturate(180%);
    border: 1px solid var(--border-strong);
    box-shadow: var(--shadow-xl);
    transform-origin: top;
    transform: translateY(-12px) scale(0.98);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--dur-base) var(--ease-out),
      transform var(--dur-base) var(--ease-out), visibility var(--dur-base);
  }
  .nav-menu.is-open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0) scale(1);
  }
  .nav-links {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
  }
  .nav-links a {
    padding: 0.85rem 1rem;
    font-size: var(--text-base);
  }
  .nav-menu .nav-actions {
    margin-top: var(--space-xs);
    flex-direction: column;
    align-items: stretch;
  }
  .nav-menu .btn {
    justify-content: center;
  }
}