@layer shell {
  .app-shell {
    display: grid;
    grid-template: 64px minmax(0, 1fr) / var(--sidebar) minmax(0, 1fr);
    width: 100vw;
    height: 100dvh;
    background: var(--balaur-surface-page);
  }
  .app-shell.sidebar-closed { --sidebar: 0px; }

  /* The grid/flex display values above override the UA `[hidden]{display:none}`,
     so the hidden app shell and dismissed gate need explicit overrides. */
  .app-shell[hidden] { display: none; }
  #vaultLanding[hidden] { display: none; }

  .vault-landing {
    position: fixed;
    inset: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--balaur-space-4);
    padding: var(--balaur-space-5);
    background: var(--balaur-surface-page);
    color: var(--balaur-content-on-dark);
    text-align: center;
    z-index: 100;
  }
  .vault-landing-wordmark {
    margin: 0;
    color: var(--balaur-action-primary);
    font: 600 var(--balaur-text-xl)/1 var(--balaur-font-display);
    letter-spacing: .04em;
  }
  .vault-landing-hint {
    margin: 0;
    max-width: 34ch;
    color: var(--balaur-content-on-dark-muted);
    font-size: var(--balaur-text-sm);
  }
  .vault-landing #openVaultFolder { margin-block-start: var(--balaur-space-2); }
  #vaultLandingMessage {
    margin: 0;
    min-height: 1.2em;
    max-width: 48ch;
    color: var(--balaur-status-danger);
    font-size: var(--balaur-text-sm);
  }
  @media (prefers-reduced-motion: no-preference) {
    .vault-landing { animation: vault-landing-fade 240ms ease-out; }
  }
  @keyframes vault-landing-fade {
    from { opacity: 0; }
    to { opacity: 1; }
  }

  .topbar {
    grid-column: 1 / -1;
    display: grid;
    grid-template-columns: var(--sidebar) minmax(0, 1fr) auto;
    align-items: center;
    border-block-end: 2px solid var(--balaur-color-outline);
    background: var(--balaur-texture-oak);
    box-shadow: inset 0 1px rgb(255 255 255 / 12%);
    z-index: 20;
  }
  .brand {
    height: 64px;
    padding-inline: 20px;
    display: flex;
    align-items: center;
    gap: 11px;
    border-inline-end: 1px solid var(--balaur-border-default);
    overflow: hidden;
    white-space: nowrap;
  }
  .brand-mark {
    position: relative;
    width: 30px;
    height: 30px;
    flex: 0 0 auto;
    color: var(--balaur-action-primary);
  }
  .brand-coil {
    position: absolute;
    inset: 4px;
    border: 2px solid currentColor;
    border-inline-start-color: transparent;
    border-radius: 50%;
    transform: rotate(-28deg);
  }
  .brand-coil::after {
    content: "";
    position: absolute;
    right: -4px;
    top: -3px;
    width: 8px;
    height: 8px;
    border: 2px solid var(--balaur-color-outline);
    background: var(--balaur-action-assistant);
    transform: rotate(32deg);
  }
  .brand-eye {
    position: absolute;
    right: 7px;
    top: 7px;
    width: 3px;
    height: 3px;
    background: var(--balaur-color-outline);
  }
  .brand strong {
    display: block;
    color: var(--balaur-content-on-dark);
    font: 600 16px/1 var(--balaur-font-display);
    letter-spacing: .04em;
  }
  .brand small {
    display: block;
    margin-block-start: 3px;
    color: var(--balaur-content-on-dark-muted);
    font: 500 8px/1 var(--balaur-font-mono);
    letter-spacing: .13em;
    text-transform: uppercase;
  }
  .view-title {
    display: flex;
    align-items: center;
    gap: 12px;
    min-width: 0;
    padding-inline-start: 18px;
  }
  .canvas-breadcrumbs {
    display: flex;
    align-items: center;
    gap: 4px;
    height: 17px;
    max-width: min(42vw, 520px);
    overflow: hidden;
    white-space: nowrap;
  }
  .canvas-breadcrumbs button {
    max-width: 135px;
    overflow: hidden;
    border: 0;
    padding: 0;
    background: transparent;
    color: var(--balaur-content-on-dark-muted);
    font: 500 8px var(--balaur-font-mono);
    letter-spacing: .08em;
    text-overflow: ellipsis;
    text-transform: uppercase;
    cursor: pointer;
  }
  .canvas-breadcrumbs button:hover { color: var(--balaur-action-primary); }
  .canvas-breadcrumbs button[aria-current="page"] { color: var(--balaur-content-on-dark); cursor: default; }
  .canvas-breadcrumbs span { color: var(--balaur-border-default); }
  #canvasTitle {
    width: min(30vw, 340px);
    border: 0;
    outline: 0;
    padding: 0;
    background: transparent;
    color: var(--balaur-content-on-dark);
    font: 600 15px/1.2 var(--balaur-font-display);
  }
  #canvasTitle:focus-visible {
    outline: 2px solid var(--balaur-border-focus);
    outline-offset: 4px;
  }
  .canvas-title-row {
    display: flex;
    align-items: center;
    gap: 9px;
    min-width: 0;
  }
  .canvas-icon-picker { position: relative; display: inline-flex; flex: 0 0 auto; }
  .canvas-icon-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 30px;
    height: 30px;
    border: 1px solid var(--balaur-border-default);
    border-radius: var(--balaur-radius-control);
    background: var(--balaur-color-soot-900);
    box-shadow: inset 1px 1px rgb(255 255 255 / 8%);
    color: var(--balaur-content-on-dark);
    font-size: 15px;
    line-height: 1;
    cursor: pointer;
    transition: border-color .15s ease, transform .15s ease;
  }
  .canvas-icon-toggle:hover { border-color: var(--balaur-action-primary); transform: translateY(-1px); }
  .canvas-icon-toggle[aria-expanded="true"] { border-color: var(--balaur-action-primary); box-shadow: inset 0 0 0 1px var(--balaur-action-primary); }
  .canvas-icon-panel {
    position: absolute;
    top: calc(100% + 9px);
    inset-inline-start: 0;
    z-index: 40;
    width: 322px;
    max-height: calc(100dvh - 96px);
    overflow-y: auto;
    border: 2px solid var(--balaur-color-outline);
    border-radius: var(--balaur-radius-panel);
    padding: 10px;
    background: var(--balaur-surface-oak-raised);
    box-shadow: inset 1px 1px var(--balaur-border-default), var(--balaur-shadow-overlay);
    scrollbar-width: thin;
    scrollbar-color: var(--balaur-color-leather-800) transparent;
  }
  .canvas-icon-panel[hidden] { display: none; }
  .canvas-icon-head {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-block-end: 9px;
  }
  .canvas-icon-head span {
    color: var(--balaur-content-on-dark-muted);
    font: 500 9px var(--balaur-font-mono);
    letter-spacing: .16em;
    text-transform: uppercase;
  }
  .canvas-icon-reset {
    border: 1px solid var(--balaur-border-default);
    border-radius: var(--balaur-radius-control);
    padding: 3px 8px;
    background: transparent;
    color: var(--balaur-content-on-dark-muted);
    font: 500 9px var(--balaur-font-mono);
    letter-spacing: .06em;
    cursor: pointer;
    transition: color .15s ease, border-color .15s ease;
  }
  .canvas-icon-reset:hover { color: var(--balaur-action-primary); border-color: var(--balaur-action-primary); }
  .canvas-icon-group { margin-block-end: 9px; }
  .canvas-icon-group p {
    margin: 0 0 3px;
    color: var(--balaur-content-on-dark-muted);
    font: 500 8px var(--balaur-font-mono);
    letter-spacing: .13em;
    text-transform: uppercase;
  }
  .canvas-icon-grid {
    display: grid;
    grid-template-columns: repeat(10, minmax(0, 1fr));
    gap: 2px;
  }
  .canvas-icon-grid button {
    display: flex;
    align-items: center;
    justify-content: center;
    height: 28px;
    border: 0;
    border-radius: 1px;
    padding: 0;
    background: transparent;
    font-size: 15px;
    line-height: 1;
    cursor: pointer;
    transition: transform .12s ease, background-color .12s ease;
  }
  .canvas-icon-grid button:hover,
  .canvas-icon-grid button:focus-visible {
    background: var(--balaur-surface-oak);
    transform: scale(1.25);
  }
  .canvas-icon-custom {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-block-start: 10px;
    padding-block-start: 9px;
    border-block-start: 1px solid var(--balaur-border-subtle);
  }
  .canvas-icon-custom span {
    color: var(--balaur-content-on-dark-muted);
    font: 500 8px var(--balaur-font-mono);
    letter-spacing: .13em;
    text-transform: uppercase;
    white-space: nowrap;
  }
  .canvas-icon-custom input {
    width: 100%;
    min-width: 0;
    border: 1px solid var(--balaur-border-default);
    border-radius: var(--balaur-radius-control);
    padding: 5px 8px;
    background: var(--balaur-color-soot-900);
    color: var(--balaur-content-on-dark);
    font-size: 13px;
  }
  .canvas-icon-custom input:focus-visible { outline: 0; border-color: var(--balaur-border-focus); }
  .app-views {
    display: flex;
    align-items: center;
    gap: 2px;
    margin-inline-start: 10px;
    padding: 3px;
    border: 1px solid var(--balaur-color-outline);
    border-radius: var(--balaur-radius-control);
    background: var(--balaur-color-soot-900);
  }
  .app-views button {
    min-height: 30px;
    padding-inline: 10px;
    border: 0;
    border-radius: 1px;
    background: transparent;
    color: var(--balaur-content-on-dark-muted);
    font: 500 9px var(--balaur-font-mono);
    cursor: pointer;
  }
  .app-views button:hover { color: var(--balaur-content-on-dark); }
  .app-views button.active {
    background: var(--balaur-surface-oak-raised);
    color: var(--balaur-action-primary);
  }
  .icon-btn {
    min-width: var(--balaur-target-min);
    min-height: var(--balaur-target-min);
    border: 0;
    background: transparent;
    color: var(--balaur-content-on-dark-muted);
    cursor: pointer;
  }
  .top-actions {
    display: flex;
    align-items: center;
    gap: 8px;
    padding-inline: 18px;
  }
  .save-state {
    margin-inline-end: 8px;
    color: var(--balaur-content-on-dark-muted);
    font: 10px var(--balaur-font-mono);
    white-space: nowrap;
  }
  .save-state i {
    display: inline-block;
    width: 6px;
    height: 6px;
    margin-inline-end: 6px;
    border-radius: 50%;
    background: var(--balaur-status-success);
  }
  .button {
    min-height: var(--balaur-target-min);
    border: 1px solid var(--balaur-border-default);
    border-radius: var(--balaur-radius-control);
    padding: 8px 12px;
    background: var(--balaur-surface-oak-raised);
    box-shadow: inset 1px 1px rgb(255 255 255 / 10%);
    color: var(--balaur-content-on-dark);
    font-size: 11px;
    font-weight: 600;
    cursor: pointer;
  }
  .button:hover { border-color: var(--balaur-action-primary); }
  .button.primary {
    border-color: var(--balaur-color-outline);
    background: var(--balaur-action-primary);
    box-shadow: inset 0 0 0 1px rgb(255 255 255 / 24%);
    color: var(--balaur-content-on-paper);
  }
  .button.primary:hover { background: var(--balaur-surface-parchment-raised); }
  .button.assistant-button {
    border-color: var(--balaur-color-outline);
    background: var(--balaur-surface-oak-raised);
    color: var(--balaur-content-on-dark);
  }

  .sidebar {
    grid-row: 2;
    grid-column: 1;
    display: flex;
    flex-direction: column;
    gap: var(--balaur-space-5);
    overflow: hidden auto;
    border-inline-end: 2px solid var(--balaur-color-outline);
    padding: var(--balaur-space-4) 10px;
    background: var(--balaur-texture-oak);
    color: var(--balaur-content-on-dark);
    scroll-padding-block: var(--balaur-space-4);
    scrollbar-width: thin;
    scrollbar-color: var(--balaur-color-leather-800) transparent;
    z-index: 10;
  }
  .sidebar::-webkit-scrollbar { width: 8px; }
  .sidebar::-webkit-scrollbar-track { background: transparent; }
  .sidebar::-webkit-scrollbar-thumb {
    border: 2px solid var(--balaur-color-oak-900);
    border-radius: 4px;
    background: var(--balaur-color-leather-800);
  }
  .section-heading {
    display: flex;
    align-items: center;
    gap: 6px;
    padding-inline: 5px;
  }
  .section-label {
    display: flex;
    align-items: center;
    gap: 8px;
    flex: 1;
    margin: 0;
    color: var(--balaur-content-on-dark-muted);
    font: 500 9px var(--balaur-font-mono);
    letter-spacing: .16em;
  }
  .section-label::after {
    content: "";
    height: 1px;
    flex: 1;
    background: linear-gradient(90deg, var(--balaur-border-default), transparent);
  }
  .section-actions { display: flex; align-items: center; gap: 4px; }
  .tiny-btn {
    min-width: var(--balaur-target-min);
    min-height: var(--balaur-target-min);
    border: 0;
    background: transparent;
    color: var(--balaur-content-on-dark-muted);
    cursor: pointer;
  }
  .tiny-btn:hover { color: var(--balaur-action-primary); }
  #newCanvas:hover, #newGroup:hover { transform: rotate(90deg); }
  .nav-item {
    position: relative;
    display: flex;
    align-items: center;
    gap: 10px;
    width: 100%;
    min-height: var(--balaur-target-min);
    border: 1px solid transparent;
    border-radius: var(--balaur-radius-control);
    padding: 8px 9px;
    background: transparent;
    color: var(--balaur-content-on-dark-muted);
    font-size: 11px;
    text-align: start;
    cursor: pointer;
  }
  /* Carved recess that carries each row's glyph or library dot. */
  .nav-item > span:first-child {
    display: grid;
    place-items: center;
    width: 24px;
    height: 24px;
    flex: 0 0 auto;
    border-radius: var(--balaur-radius-control);
    background: var(--balaur-color-soot-950);
    box-shadow: inset 0 1px 3px rgb(0 0 0 / 55%), inset 0 -1px 0 rgb(255 255 255 / 7%);
    color: var(--balaur-content-on-dark-muted);
    font: 500 11px var(--balaur-font-mono);
  }
  .nav-item:hover {
    border-color: var(--balaur-border-subtle);
    background: var(--balaur-surface-oak-raised);
    box-shadow: inset 0 1px 0 rgb(255 255 255 / 6%);
    color: var(--balaur-content-on-dark);
    transform: translateX(2px);
  }
  .nav-item:hover > span:first-child {
    color: var(--balaur-content-on-dark);
    box-shadow: inset 0 1px 2px rgb(0 0 0 / 45%), inset 0 -1px 0 rgb(255 255 255 / 12%);
  }
  .nav-item.active {
    border-color: var(--balaur-border-default);
    background:
      linear-gradient(90deg, rgb(242 193 78 / 10%), transparent 55%),
      var(--balaur-surface-oak-raised);
    box-shadow: inset 0 1px 0 rgb(255 255 255 / 8%);
    color: var(--balaur-content-on-dark);
  }
  /* Brass rail marking the active canvas or filter. */
  .nav-item.active::before {
    content: "";
    position: absolute;
    inset-block: 7px;
    inset-inline-start: -1px;
    width: 2px;
    border-radius: 1px;
    background: var(--balaur-action-primary);
    box-shadow: 0 0 8px rgb(242 193 78 / 55%);
  }
  .nav-item.active > span:first-child {
    color: var(--balaur-action-primary);
    box-shadow: inset 0 1px 3px rgb(0 0 0 / 55%), inset 0 0 0 1px rgb(242 193 78 / 28%);
  }
  .nav-item.active b { font-weight: 600; }
  .nav-item em {
    margin-inline-start: auto;
    padding: 2px 7px;
    border-radius: var(--balaur-radius-control);
    background: var(--balaur-color-soot-950);
    box-shadow: inset 0 1px 2px rgb(0 0 0 / 50%);
    color: var(--balaur-content-on-dark-muted);
    font: 10px var(--balaur-font-mono);
    font-style: normal;
  }
  .nav-item.active em { color: var(--balaur-action-primary); }
  .canvas-list-item { padding-inline-start: calc(9px + var(--canvas-depth, 0) * 14px); }
  .canvas-list-item b {
    min-width: 0;
    overflow: hidden;
    font-weight: 500;
    text-overflow: ellipsis;
    white-space: nowrap;
  }
  .canvas-list-item.active b { color: var(--balaur-action-primary); }
  .dot { width: 7px; height: 7px; border-radius: 50%; }
  .red { background: var(--balaur-canvas-red); color: var(--balaur-canvas-red); }
  .green { background: var(--balaur-canvas-green); color: var(--balaur-canvas-green); }
  .orange { background: var(--balaur-canvas-orange); color: var(--balaur-canvas-orange); }
  .purple { background: var(--balaur-canvas-purple); color: var(--balaur-canvas-purple); }
  .nav-item:hover .dot, .nav-item.active .dot { box-shadow: 0 0 7px 1px currentColor; }
  .sidebar-bottom {
    display: flex;
    flex-direction: column;
    gap: 2px;
    margin-block-start: auto;
  }
  .tip {
    display: flex;
    gap: 10px;
    margin-block-end: 8px;
    border: 1px solid var(--balaur-border-subtle);
    border-radius: var(--balaur-radius-panel);
    background: linear-gradient(180deg, var(--balaur-surface-oak-raised), var(--balaur-color-oak-900));
    box-shadow: inset 0 1px 0 rgb(255 255 255 / 7%);
    padding: 10px 12px;
    color: var(--balaur-content-on-dark-muted);
    font-size: 9px;
  }
  .tip > span { color: var(--balaur-action-assistant); font-size: 12px; }
  .tip b { color: var(--balaur-content-on-dark); font-size: 10px; }
  .tip p { margin: 2px 0 0; }
  .storage-state {
    display: flex;
    align-items: center;
    gap: 7px;
    padding: 8px 4px 2px;
    color: var(--balaur-content-on-dark-muted);
    font: 8px var(--balaur-font-mono);
  }
  .storage-state i {
    width: 5px;
    height: 5px;
    flex: 0 0 auto;
    border-radius: 50%;
    background: var(--balaur-action-primary);
    box-shadow: 0 0 6px rgb(242 193 78 / 60%);
  }
  .storage-state span {
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }
  .spec-link {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 4px;
    color: var(--balaur-content-on-dark-muted);
    font: 9px var(--balaur-font-mono);
    text-decoration: none;
  }
  .spec-link:hover { color: var(--balaur-action-primary); }
  .spec-link span { display: inline-block; }

  .familiar-control {
    position: fixed;
    right: 18px;
    bottom: 112px;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    min-height: var(--balaur-target-min);
    border: 2px solid var(--balaur-color-outline);
    background: var(--balaur-surface-oak-raised);
    box-shadow: inset 1px 1px var(--balaur-border-default), 0 0 18px rgb(242 193 78 / 20%);
    color: var(--balaur-content-on-dark);
    z-index: 24;
  }
  .familiar-glyph {
    color: var(--balaur-action-primary);
    font-size: 1.125rem;
  }
}