/**
 * <HeaderBar> — top navigation strip used on every authenticated screen.
 *
 * Markup:
 *   <header class="c-header" role="banner">
 *     <a class="c-header__brand" href="/dashboard">e-Financials MCP</a>
 *     <button type="button" class="c-header__hamburger"
 *             aria-expanded="false" aria-controls="header-nav" aria-label="Menu">
 *       <span aria-hidden="true"></span>
 *       <span aria-hidden="true"></span>
 *       <span aria-hidden="true"></span>
 *     </button>
 *     <nav class="c-header__nav" id="header-nav" aria-label="Main">
 *       <a class="c-header__link" href="/dashboard" aria-current="page">Dashboard</a>
 *       <a class="c-header__link" href="/pricing">Pricing</a>
 *     </nav>
 *     <div class="c-header__actions">
 *       <span class="c-header__plan">Pro plan</span>
 *       <!-- LanguageToggle slots in here -->
 *       <button type="button" class="c-header__avatar" aria-label="Account">JL</button>
 *     </div>
 *   </header>
 *
 * Below 640px the nav collapses behind the hamburger; initHeaderBar() wires
 * aria-expanded + outside-click + ESC.
 */

.c-header {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  padding: var(--space-3) var(--space-5);
  background: var(--bg-primary);
  border-bottom: 0.5px solid var(--border-tertiary);
}

.c-header__brand {
  flex: 0 0 auto;
  font-size: var(--font-size-h2);
  font-weight: 500;
  color: var(--text-primary);
  text-decoration: none;
  white-space: nowrap;
}

.c-header__brand:hover,
.c-header__brand:focus-visible {
  text-decoration: underline;
}

.c-header__brand:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: var(--radius-sm);
}

.c-header__nav {
  display: flex;
  align-items: center;
  gap: var(--space-5);
  flex: 1 1 auto;
}

.c-header__link {
  font-size: var(--font-size-small);
  color: var(--text-secondary);
  text-decoration: none;
  padding: var(--space-1) 0;
}

.c-header__link:hover {
  color: var(--text-primary);
}

.c-header__link[aria-current="page"] {
  color: var(--text-primary);
  font-weight: 500;
}

.c-header__link:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: var(--radius-sm);
}

.c-header__actions {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.c-header__plan {
  font-size: var(--font-size-small);
  color: var(--text-secondary);
}

.c-header__avatar {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  font-size: var(--font-size-micro);
  font-weight: 500;
  color: var(--info-text);
  background: var(--info-bg);
  border: none;
  border-radius: var(--radius-pill);
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
}

.c-header__avatar:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.c-header__hamburger {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  align-items: center;
  width: 32px;
  height: 28px;
  padding: 6px 5px;
  background: transparent;
  border: 0.5px solid var(--border-secondary);
  border-radius: var(--radius-sm);
  cursor: pointer;
  -webkit-appearance: none;
  appearance: none;
}

.c-header__hamburger span {
  display: block;
  width: 100%;
  height: 1.5px;
  background: var(--text-primary);
  border-radius: 1px;
}

.c-header__hamburger:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

/* --- Responsive: collapse nav into hamburger below 640px --- */

/* Hide the optional plan / build-meta chips one breakpoint early so the
   dashboard #app-header fits at 640-767px viewports — the row still has
   brand + nav + lang toggle + avatar + Log out, and the chips are extra
   chrome that's only valuable on wider screens. Public headers (no chips)
   are unaffected. */
@media (max-width: 767.98px) {
  .c-header__plan {
    display: none;
  }
}

@media (max-width: 639.98px) {
  .c-header {
    flex-wrap: wrap;
    position: relative;
  }

  .c-header__hamburger {
    display: flex;
    order: 2;
    margin-left: auto;
  }

  .c-header__actions {
    order: 3;
    gap: var(--space-2);
  }

  .c-header__nav {
    order: 4;
    flex-basis: 100%;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding-top: var(--space-3);
    border-top: 0.5px solid var(--border-tertiary);
    margin-top: var(--space-3);
  }

  .c-header__nav[hidden] {
    display: none;
  }

  .c-header__link {
    padding: var(--space-2) 0;
  }
}