/* Header: brand on the left, nav bubble + settings button on the right. */
.site-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  padding: 0.85rem 1.5rem;
  background: var(--header-bg);
  backdrop-filter: saturate(120%) blur(8px);
  position: sticky;
  top: 0;
  z-index: 10;
}
.site-header .brand {
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: var(--text-lg);
  color: var(--text);
  letter-spacing: -0.02em;
  margin-right: auto;
}
.site-header .brand:hover {
  text-decoration: none;
}

.nav-bubble {
  display: flex;
  gap: 2px;
  padding: 4px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-pill);
  box-shadow: var(--shadow);
}
.nav-bubble a {
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-pill);
  color: var(--muted);
  font-size: var(--text-sm);
  font-weight: 500;
  transition:
    background var(--duration),
    color var(--duration);
}
.nav-bubble a:hover {
  color: var(--text);
  background: var(--surface-2);
  text-decoration: none;
}
.nav-bubble a[aria-current="page"] {
  color: var(--accent);
  background: var(--accent-soft);
  font-weight: 600;
}

/* Round settings button; a status dot flags an AI mentor problem. */
.settings-toggle {
  position: relative;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  padding: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 50%;
  box-shadow: var(--shadow);
  color: var(--muted);
  cursor: pointer;
  transition:
    color var(--duration),
    border-color var(--duration);
}
.settings-toggle:hover {
  color: var(--text);
  border-color: var(--accent);
}
.settings-alert {
  position: absolute;
  top: 1px;
  right: 1px;
}

/* Settings menu (native popover: light dismiss and Escape come for free). */
.settings-menu {
  inset: auto;
  position: fixed;
  top: 4.4rem;
  right: 1.5rem;
  margin: 0;
  min-width: 250px;
  padding: 0.4rem;
  background: var(--surface);
  color: var(--text);
  border: 1px solid var(--card-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
}
.settings-menu hr {
  border: none;
  border-top: 1px solid var(--border);
  margin: 0.35rem 0.5rem;
}
.menu-form {
  margin: 0;
}
.menu-item {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  width: 100%;
  min-height: 44px;
  padding: 0.5rem 0.8rem;
  background: none;
  border: none;
  border-radius: var(--radius-md);
  color: var(--text);
  font-size: var(--text-sm);
  text-align: left;
  cursor: pointer;
}
.menu-item:hover {
  background: var(--surface-2);
}
.menu-item > i,
.menu-item > .fi,
.menu-item > .dot {
  width: 1.1rem;
  text-align: center;
  color: var(--muted);
}
.menu-item > .dot {
  width: 0.6rem;
  margin: 0 0.25rem;
}
.menu-value {
  margin-left: auto;
  font-size: var(--text-xs);
  font-weight: 600;
  color: var(--muted);
}

/* Mobile burger toggle (hidden on desktop) */
.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 4px;
  width: 40px;
  height: 40px;
  padding: 10px 10px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 50%;
  box-shadow: var(--shadow);
  cursor: pointer;
}
.nav-toggle-bar {
  display: block;
  width: 100%;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
  transition:
    transform 0.2s ease,
    opacity 0.2s ease;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(1) {
  transform: translateY(6px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] .nav-toggle-bar:nth-child(3) {
  transform: translateY(-6px) rotate(-45deg);
}

@media (max-width: 720px) {
  .site-header {
    flex-wrap: wrap;
    padding: 0.7rem 1rem;
  }
  .nav-toggle {
    display: flex;
  }
  /* The nav drops below as a card; the burger opens it. */
  .nav-bubble {
    display: none;
    order: 1;
    width: 100%;
    flex-direction: column;
    padding: 0.4rem;
    border-radius: var(--radius-lg);
  }
  .nav-bubble.open {
    display: flex;
  }
  .nav-bubble a {
    padding: 0.65rem 0.9rem;
    border-radius: var(--radius-md);
    font-size: var(--text-base);
  }
  .settings-menu {
    top: 4rem;
    right: 1rem;
  }
}