/* --- Error Byte Viewer --- */
  .error-sector {
    width: 18px;
    height: 12px;
    border-radius: 2px;
    cursor: pointer;
    flex-shrink: 0;
    font-size: 7px;
    line-height: 12px;
    text-align: center;
    font-family: "Cascadia Code", "Consolas", monospace;
  }

  .error-sector.ok {
    background: var(--accent);
    opacity: 0.25;
  }

  .error-sector.err {
    background: var(--color-error);
    color: var(--bg);
  }

  .error-sector.no-data {
    background: var(--border);
    opacity: 0.3;
  }

  /* --- File Viewer --- */
  /* --- Separator Editor --- */
  .sep-editor-layout {
    display: flex; flex-direction: column; height: 100%; overflow: hidden;
  }
  .sep-editor-list {
    margin-bottom: 12px;
    overflow-y: auto; flex: 1; min-height: 0;
  }
  .sep-editor-form {
    flex-shrink: 0; padding-top: 8px; border-top: 1px solid var(--border);
  }
  .modal-body:has(.sep-editor-layout) { overflow-y: hidden; display: flex; flex-direction: column; }

  .sep-editor-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 4px 0;
    border-bottom: 1px solid var(--border);
  }

  .sep-editor-preview {
    font-family: 'C64 Pro Mono', monospace;
    font-size: 13px;
    flex: 1;
    white-space: pre;
  }

  .sep-editor-btn {
    padding: 2px 8px;
    font-size: 12px;
    font-family: inherit;
    border: 1px solid var(--border);
    border-radius: 3px;
    background: var(--bg);
    color: var(--text);
    cursor: pointer;
  }

  .sep-editor-btn:hover {
    background: var(--hover);
  }

  .sep-editor-btn.danger:hover {
    background: var(--color-error);
    color: var(--bg);
    border-color: var(--color-error);
  }

  .sep-editor-input {
    font-family: 'C64 Pro Mono', monospace;
    font-size: 14px;
    width: 100%;
    background: var(--bg);
    border: 1px solid var(--accent);
    border-radius: 3px;
    padding: 4px 8px;
    color: var(--text);
    outline: none;
  }

  .hex-nav-field {
    cursor: pointer;
    padding: 2px 4px;
    border-radius: 3px;
    background: var(--bg);
    border: 1px solid var(--border);
    min-width: 3ch;
    display: inline-block;
    text-align: center;
  }

  .hex-nav-field:hover {
    border-color: var(--accent);
    color: var(--accent);
  }

  .hex-nav-field .hex-input {
    width: 3ch;
    font-size: inherit;
  }

  .hex-nav-group {
    display: inline-flex;
    align-items: center;
    gap: 2px;
  }

  .hex-nav-arrows {
    display: inline-flex;
    flex-direction: column;
    gap: 1px;
  }

  .hex-nav-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 14px;
    height: 10px;
    border: 1px solid var(--border);
    border-radius: 2px;
    cursor: pointer;
    font-size: 7px;
    color: var(--text-muted);
    background: var(--bg);
    line-height: 1;
  }

  .hex-nav-btn:hover {
    background: var(--accent);
    color: var(--bg);
    border-color: var(--accent);
  }

  .hex-byte.editing {
    background: var(--bg);
    outline: 1px solid var(--accent);
    border-radius: 2px;
    color: var(--accent);
  }

  .hex-byte.modified {
    color: var(--color-dir);
  }

  .hex-highlight {
    background: rgba(184,199,111,0.3);
    border-radius: 2px;
    outline: 1px solid var(--c64-highlight);
  }

  .hex-ascii {
    color: var(--accent);
    font-family: 'C64 Pro Mono', monospace;
  }

  .hex-separator {
    width: 1px;
    background: var(--border);
    margin: 0 8px;
    flex-shrink: 0;
  }

  /* ── Compare modal ───────────────────────────────────────────────────
     Tabbed layout: pinned tab bar + scrollable content area. Mirrors the
     bam-tab pattern. */
  .cmp-layout {
    display: flex;
    flex-direction: column;
    flex: 1;
    min-height: 0;
    overflow: hidden;
  }
  .modal-body:has(.cmp-layout) {
    overflow-y: hidden;
    display: flex;
    flex-direction: column;
  }
  .cmp-tabs {
    display: flex;
    gap: 0;
    margin-bottom: 10px;
    border-bottom: 1px solid var(--border);
    flex-shrink: 0;
  }
  .cmp-tab {
    padding: 5px 14px;
    font-size: 12px;
    cursor: pointer;
    color: var(--text-muted);
    border-bottom: 2px solid transparent;
    transition: color 0.15s, border-color 0.15s;
  }
  .cmp-tab:hover { color: var(--text); }
  .cmp-tab.active {
    color: var(--accent);
    border-bottom-color: var(--accent);
  }
  .cmp-tab-scroll {
    overflow-y: auto;
    flex: 1;
    min-height: 0;
  }
  .cmp-summary {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
    margin-bottom: 14px;
  }
  .cmp-summary-card {
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 8px 10px;
    font-size: 12px;
  }
  .cmp-summary-card .cmp-summary-num {
    font-size: 18px;
    font-weight: bold;
    line-height: 1.1;
    color: var(--text);
  }
  .cmp-summary-card .cmp-summary-label {
    color: var(--text-muted);
    margin-top: 2px;
  }
  .cmp-summary-card.cmp-c-identical .cmp-summary-num { color: var(--color-recover); }
  .cmp-summary-card.cmp-c-differ    .cmp-summary-num { color: var(--color-warn); }
  .cmp-summary-card.cmp-c-only-a    .cmp-summary-num { color: var(--color-error); }
  .cmp-summary-card.cmp-c-only-b    .cmp-summary-num { color: var(--accent); }

  .cmp-section-title {
    font-weight: bold;
    margin: 12px 0 6px;
    color: var(--text);
  }
  .cmp-section-title .cmp-section-count {
    color: var(--text-muted);
    font-weight: normal;
    font-size: 12px;
    margin-left: 6px;
  }

  .cmp-table {
    width: 100%;
    border-collapse: collapse;
    font-size: 12px;
    table-layout: fixed;
  }
  .cmp-table th, .cmp-table td {
    padding: 3px 8px;
    text-align: left;
    border-bottom: 1px solid var(--border);
    overflow: hidden;
    text-overflow: ellipsis;
  }
  .cmp-table th {
    color: var(--text-muted);
    font-weight: normal;
    font-size: 11px;
  }
  .cmp-table tr.cmp-section-row td {
    font-weight: bold;
    padding-top: 12px;
    padding-bottom: 4px;
    color: var(--text);
    background: var(--hover);
    border-bottom: 1px solid var(--border);
  }
  .cmp-table tr.cmp-section-row:first-child td {
    padding-top: 4px;
  }
  .cmp-table td.cmp-marker, .cmp-marker {
    text-align: center;
    font-size: 11px;
    overflow: visible;
    text-overflow: clip;
    padding-left: 4px;
    padding-right: 4px;
  }
  .cmp-table td.cmp-fname,
  .cmp-petscii {
    font-family: 'C64 Pro Mono', monospace;
    white-space: nowrap;
  }
  .cmp-marker-eq      { color: var(--color-recover); }
  .cmp-marker-ne      { color: var(--color-warn); }
  .cmp-marker-only-a  { color: var(--color-error); }
  .cmp-marker-only-b  { color: var(--accent); }

  .cmp-legend {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
    padding: 8px 10px;
    margin-bottom: 8px;
    font-size: 11px;
    color: var(--text-muted);
    background: var(--hover);
    border-radius: 4px;
  }
  .cmp-legend-item {
    display: inline-flex;
    align-items: center;
    gap: 6px;
  }
  .cmp-legend-item .cmp-marker {
    display: inline-block;
    min-width: 16px;
  }

  /* Side-by-side directory listing (Directory tab) */
  .cmp-side-by-side {
    display: grid;
    grid-template-columns: 1fr 20px 1fr;
    gap: 0 8px;
    font-size: 12px;
  }
  .cmp-side-col {
    display: flex;
    flex-direction: column;
  }
  .cmp-side-header {
    font-weight: bold;
    padding: 6px 8px;
    background: var(--hover);
    border-radius: 3px;
    margin-bottom: 4px;
  }
  .cmp-side-row {
    display: flex;
    gap: 6px;
    padding: 2px 8px;
    align-items: baseline;
  }
  .cmp-side-row.cmp-r-eq   { background: transparent; }
  .cmp-side-row.cmp-r-ne   { background: rgba(255, 200, 0, 0.08); }
  .cmp-side-row.cmp-r-only-a, .cmp-side-row.cmp-r-only-b { background: rgba(255, 100, 100, 0.08); }
  .cmp-side-row .cmp-side-blocks {
    width: 36px;
    text-align: right;
    color: var(--text-muted);
    flex-shrink: 0;
  }
  .cmp-side-row .cmp-side-name {
    flex: 1;
    font-family: 'C64 Pro Mono', monospace;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }
  .cmp-side-row .cmp-side-type {
    width: 32px;
    color: var(--text-muted);
    flex-shrink: 0;
  }
  .cmp-side-row.cmp-r-empty {
    visibility: hidden;
  }
  .cmp-side-mid {
    text-align: center;
    color: var(--text-muted);
    font-size: 11px;
    padding-top: 2px;
  }

  /* Sectors tab */
  .cmp-sector-legend {
    display: flex;
    flex-wrap: wrap;
    gap: 14px;
    padding: 6px 10px;
    margin-bottom: 8px;
    font-size: 11px;
    color: var(--text-muted);
    background: var(--hover);
    border-radius: 4px;
  }
  .cmp-sector-legend .cmp-legend-box {
    width: 12px;
    height: 8px;
    border-radius: 2px;
    display: inline-block;
  }
  .cmp-sec-eq { background: var(--border); opacity: 0.7; }
  .cmp-sec-ne { background: var(--color-warn); }

  .cmp-sector-map {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 8px;
    overflow: auto;
    max-height: 50vh;
  }

  .cmp-sector-hex {
    margin-top: 14px;
  }
  .cmp-sector-hex:empty {
    display: none;
  }
  .cmp-sector-hex-header {
    font-weight: bold;
    margin-bottom: 8px;
    font-size: 13px;
  }
  /* Wraps the standard .hex-editor in a panel so it visually anchors as
     a drill-down beneath the sector map. */
  .cmp-hex-editor {
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 4px;
    padding: 6px 8px;
    overflow-x: auto;
  }
  /* A/B side label sits to the left of the standard offset column. */
  .cmp-hex-row .cmp-hex-side {
    width: 1.5ch;
    color: var(--text-muted);
    text-align: right;
    padding-right: 6px;
    font-family: "Cascadia Code", "Consolas", monospace;
    flex-shrink: 0;
  }
  /* Pair groups: keep A and B visually together, separate row-pairs
     with a faint divider. */
  .cmp-hex-row + .cmp-hex-row {
    /* even-numbered (B) rows get no divider; odd row-pairs are separated */
  }
  .cmp-hex-row:nth-of-type(even) {
    border-bottom: 1px dotted var(--border);
    padding-bottom: 1px;
    margin-bottom: 1px;
  }
  /* Highlight a differing byte / PETSCII char. Use the warn token so
     the diff colour matches the marker icons and sector-map cells. */
  .cmp-hex-editor .hex-byte.cmp-hex-diff,
  .cmp-hex-editor .hex-char.cmp-hex-diff {
    background: var(--color-warn);
    color: var(--bg);
    border-radius: 2px;
  }
  /* Override the existing hex-byte:hover so a diff stays visible while
     hovering — the warn highlight is the more important signal. */
  .cmp-hex-editor .hex-byte.cmp-hex-diff:hover {
    background: var(--color-warn);
    color: var(--bg);
  }

  /* ── File Chains viewer ──────────────────────────────────────────────
     One card per file, with a header strip (type badge, filename, file
     structure, sector count) and a body listing each chain category as
     a row of T:S chips connected by →. GEOS VLIR files get separate
     rows for the info block, VLIR index, and each record chain — so
     the per-record structure is visible at a glance. */
  .fchain-list {
    display: flex;
    flex-direction: column;
    gap: 10px;
  }

  .fchain-summary {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 8px 12px;
    margin-bottom: 4px;
    font-size: 12px;
    color: var(--text-muted);
    background: var(--hover);
    border-radius: 4px;
  }
  .fchain-summary b { color: var(--text); }
  .fchain-summary-sep { color: var(--border); }

  .fchain-card {
    border: 1px solid var(--border);
    border-radius: 4px;
    overflow: hidden;
  }
  .fchain-header {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 12px;
    background: var(--hover);
    border-bottom: 1px solid var(--border);
  }
  .fchain-name {
    flex: 1;
    font-family: 'C64 Pro Mono', monospace;
    font-size: 13px;
    color: var(--text);
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }
  .fchain-struct {
    font-size: 11px;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
  }
  .fchain-count {
    font-size: 11px;
    color: var(--text-muted);
  }
  .fchain-badge {
    padding: 2px 7px;
    border-radius: 3px;
    font-size: 10px;
    font-weight: bold;
    font-family: "Cascadia Code", "Consolas", monospace;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    flex-shrink: 0;
  }
  .fchain-badge-type {
    background: var(--accent);
    color: var(--bg);
  }
  .fchain-badge-type.fchain-badge-geos {
    background: var(--color-warn-gold);
    color: var(--bg);
  }
  .fchain-badge-type.fchain-badge-geos-seq {
    background: var(--color-warn);
    color: var(--bg);
  }
  .fchain-badge-type.fchain-badge-rel {
    background: var(--color-warn);
    color: var(--bg);
  }

  .fchain-body {
    padding: 8px 12px;
    display: flex;
    flex-direction: column;
    gap: 4px;
  }
  .fchain-row {
    display: flex;
    align-items: baseline;
    gap: 10px;
    flex-wrap: wrap;
  }
  .fchain-row-label {
    flex-shrink: 0;
    width: 110px;
    font-size: 11px;
    font-weight: bold;
    color: var(--text-muted);
  }
  .fchain-label-main      { color: var(--text); }
  .fchain-label-info      { color: var(--color-warn-gold); }
  .fchain-label-index     { color: var(--color-warn-gold); }
  .fchain-label-record    { color: var(--accent); }
  .fchain-label-record-empty { color: var(--text-muted); font-weight: normal; }
  .fchain-label-side      { color: var(--color-warn); }

  .fchain-row-sectors {
    display: flex;
    flex-wrap: wrap;
    gap: 3px;
    align-items: center;
    flex: 1;
    min-width: 0;
  }

  .fchain-chip {
    font-family: "Cascadia Code", "Consolas", monospace;
    font-size: 11px;
    padding: 1px 6px;
    border-radius: 3px;
    background: var(--bg);
    border: 1px solid var(--border);
    color: var(--text);
    white-space: nowrap;
  }
  .fchain-chip-main   { border-color: color-mix(in srgb, var(--accent) 60%, var(--border)); }
  .fchain-chip-info   { border-color: color-mix(in srgb, var(--color-warn-gold) 60%, var(--border)); color: var(--color-warn-gold); }
  .fchain-chip-index  { border-color: color-mix(in srgb, var(--color-warn-gold) 60%, var(--border)); color: var(--color-warn-gold); }
  .fchain-chip-record { border-color: color-mix(in srgb, var(--accent) 60%, var(--border)); }
  .fchain-chip-side   { border-color: color-mix(in srgb, var(--color-warn) 60%, var(--border)); color: var(--color-warn); }

  .fchain-arrow {
    color: var(--text-muted);
    font-size: 9px;
    opacity: 0.7;
  }

  .fchain-empty-note {
    font-size: 11px;
    color: var(--text-muted);
    font-style: italic;
  }

  .fchain-loop {
    font-size: 11px;
    color: var(--color-error);
    font-weight: bold;
    margin-left: 6px;
  }