.sidebar-menu-button[hidden] { display: none; }
.sidebar-collapse-region { min-height: 0; }

@media (max-width: 900px) {
  .sidebar { overflow: visible; }
  .sidebar-header { display: grid; grid-template-columns: minmax(0, 1fr) auto; align-items: center; gap: 0.6rem; }
  .sidebar-header .brand { min-width: 0; }
  .sidebar-header .sidebar-menu-button { grid-column: 2; grid-row: 1; width: var(--tap-target); min-height: var(--tap-target); border-color: var(--color-border-subtle); }
  .sidebar-quick-actions { grid-column: 1 / -1; grid-row: 2; margin-top: 0; }
  .toolbar-group { min-width: 0; }
  .sidebar-quick-actions :is(.sidebar-search-trigger, .sidebar-top-button, .sidebar-rss-button, .sidebar-language-button) { min-height: var(--tap-target); }
  .sidebar-collapse-region {
    position: absolute;
    top: calc(100% - 1px);
    right: -1px;
    left: -1px;
    max-height: calc(100dvh - 10rem - env(safe-area-inset-top));
    overflow-y: auto;
    border: 1px solid var(--color-border-subtle);
    border-top: 0;
    border-radius: 0 0 var(--radius-medium) var(--radius-medium);
    background: var(--color-surface);
    box-shadow: var(--shadow-elevated);
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    transition: opacity var(--transition-fast), transform var(--transition-normal), visibility 0s;
  }
  .sidebar-collapse-inner { padding: 0.75rem; padding-bottom: max(0.75rem, env(safe-area-inset-bottom)); }
  .sidebar.is-compact .sidebar-collapse-region { opacity: 0; visibility: hidden; transform: translateY(-8px); pointer-events: none; transition: opacity var(--transition-fast), transform var(--transition-normal), visibility 0s var(--transition-normal); }
}

@media (max-width: 390px) {
  .sidebar { padding-inline: 0.6rem; }
  .brand { grid-template-columns: 38px minmax(0, 1fr); gap: 0.55rem; }
  .brand-mark { width: 38px; }
  .brand strong { font-size: 0.9rem; }
  .sidebar-quick-actions { gap: 0.25rem; }
}