:root {
  --bg: #0a0a0f;
  --panel: #12121e;
  --panel-2: #1a1a2a;
  --border: #1a1a2e;
  --border-strong: #2a2a3e;
  --fg: #c8c8d0;
  --muted: #666680;
  --faint: #444;
  --accent: #d4a054;
  --branch: #5a9bf5;
  --star: #b96a6a;
  --hidden-bg: #1f1a2a;
  --serif: 'Iowan Old Style', Charter, Georgia, Palatino, serif;
  --mono: 'SF Mono', 'Fira Code', Consolas, monospace;
}

[data-theme="light"] {
  --bg: #faf8f3;
  --panel: #ffffff;
  --panel-2: #f3efe5;
  --border: #e5e1d8;
  --border-strong: #c9bfa8;
  --fg: #1a1a1a;
  --muted: #6b6b6b;
  --faint: #a8a49c;
  --accent: #8b6f47;
  --branch: #2a6aa8;
  --star: #a03e3e;
  --hidden-bg: #f3efe5;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

body {
  background: var(--bg);
  color: var(--fg);
  font-family: var(--mono);
  height: 100vh;
  overflow: hidden;
}

#app {
  display: grid;
  grid-template-columns: 260px 1fr;
  grid-template-rows: auto 1fr auto;
  height: 100vh;
}

/* ── Header ─────────────────────────────────── */

header {
  grid-column: 1 / -1;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 16px;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
  flex-wrap: wrap;
}

header h1 {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--accent);
  letter-spacing: 0.02em;
}

.subtitle {
  font-size: 0.7rem;
  color: var(--muted);
  font-style: italic;
}

.header-actions {
  margin-left: auto;
  display: flex;
  gap: 6px;
  align-items: center;
}

button, .file-upload {
  background: var(--panel);
  border: 1px solid var(--border-strong);
  color: var(--muted);
  font-family: inherit;
  font-size: 0.7rem;
  padding: 4px 10px;
  border-radius: 3px;
  cursor: pointer;
  transition: border-color 0.12s, color 0.12s, background 0.12s;
  display: inline-block;
}

button:hover, .file-upload:hover { border-color: var(--accent); color: var(--accent); }
button.active {
  background: var(--accent);
  border-color: var(--accent);
  color: var(--bg);
  font-weight: 500;
}
button.active:hover { background: var(--accent); color: var(--bg); }
.file-upload input { display: none; }

#btn-theme { font-size: 0.9rem; padding: 2px 10px; min-width: 28px; }

/* ── Block list ─────────────────────────────── */

#block-list {
  grid-column: 1;
  border-right: 1px solid var(--border);
  background: var(--panel);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.block-list-header {
  display: flex;
  align-items: center;
  padding: 8px 12px;
  border-bottom: 1px solid var(--border);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--muted);
}

.block-list-header button { margin-left: auto; padding: 2px 8px; font-size: 0.65rem; }

#block-list-items { flex: 1; overflow-y: auto; }

.block-item {
  padding: 10px 12px 10px 9px;
  border-bottom: 1px solid var(--border);
  border-left: 3px solid transparent;
  cursor: pointer;
  transition: background 0.1s, border-color 0.1s;
}

.block-item:hover { background: var(--panel-2); }
.block-item.current { background: var(--panel-2); border-left-color: var(--accent); }

.block-item-id {
  font-size: 0.75rem;
  font-weight: 500;
  color: var(--branch);
  margin-bottom: 3px;
  display: flex;
  align-items: center;
  gap: 4px;
}

.block-item.current .block-item-id { color: var(--accent); }

.block-item-actions { margin-left: auto; display: flex; gap: 2px; opacity: 0.4; }
.block-item:hover .block-item-actions { opacity: 1; }

.item-btn {
  border: none;
  background: transparent;
  color: var(--muted);
  padding: 0 4px;
  cursor: pointer;
  font-size: 0.75rem;
}
.item-btn:hover { color: var(--accent); border-color: transparent; }
.item-btn.del:hover { color: var(--star); }

.block-item-preview {
  font-size: 0.68rem;
  color: var(--muted);
  line-height: 1.4;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.block-list-footer {
  padding: 8px 12px;
  border-top: 1px solid var(--border);
}

#filename-input {
  width: 100%;
  background: var(--bg);
  border: 1px solid var(--border-strong);
  color: var(--fg);
  font-family: inherit;
  font-size: 0.7rem;
  padding: 4px 8px;
  border-radius: 3px;
  outline: none;
}

#filename-input:focus { border-color: var(--accent); }

.empty-list {
  padding: 16px;
  color: var(--muted);
  font-style: italic;
  font-size: 0.7rem;
  text-align: center;
  line-height: 1.5;
}

/* ── Viewer ─────────────────────────────────── */

#viewer {
  grid-column: 2;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--bg);
}

.view-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
  flex-wrap: wrap;
}

.view-tabs { display: flex; gap: 4px; }

.view-controls { display: flex; gap: 4px; align-items: center; }
.view-controls[hidden] { display: none; }

.walk-label {
  font-size: 0.62rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-right: 2px;
}

.walk-btn { padding: 3px 8px; font-size: 0.65rem; }

.slice-bar {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 14px;
  border-bottom: 1px solid var(--border);
  background: var(--panel-2);
  flex-wrap: wrap;
  min-height: 32px;
}

.slice-chips {
  display: flex;
  gap: 4px;
  flex-wrap: wrap;
  flex: 1;
}

.slice-chip {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 2px 4px 2px 7px;
  font-size: 0.62rem;
  background: var(--panel);
  border: 1px solid var(--border-strong);
  border-radius: 3px;
  cursor: pointer;
  color: var(--fg);
}

.slice-chip:hover { border-color: var(--accent); }
.slice-chip.active { border-color: var(--accent); background: var(--bg); }
.slice-chip .slice-kill {
  padding: 0 4px;
  color: var(--muted);
  cursor: pointer;
  border-radius: 2px;
}
.slice-chip .slice-kill:hover { color: var(--star); background: var(--panel-2); }

.slice-hint {
  font-size: 0.6rem;
  color: var(--muted);
  font-style: italic;
}

#view-body {
  flex: 1;
  overflow: auto;
  min-height: 0;
}

.empty-state {
  padding: 48px 32px;
  color: var(--muted);
  font-style: italic;
  text-align: center;
  font-size: 0.85rem;
  line-height: 1.6;
}

/* ── Document view ──────────────────────────── */

.doc-view {
  padding: 24px 32px 48px;
  font-family: var(--serif);
  font-size: 15px;
  line-height: 1.6;
  color: var(--fg);
  max-width: 900px;
}

.doc-view.markdown {
  font-family: var(--mono);
  white-space: pre-wrap;
  font-size: 0.75rem;
  line-height: 1.5;
  padding: 16px;
  max-width: none;
}

.doc-view .node { margin: 0 0 16px; }
.doc-view .node-heading { display: flex; align-items: baseline; gap: 10px; margin: 0 0 4px; flex-wrap: wrap; }
.doc-view .addr {
  font-family: var(--mono);
  font-size: 0.72em;
  color: var(--muted);
  background: var(--panel-2);
  padding: 2px 6px;
  border-radius: 2px;
  white-space: nowrap;
}
.doc-view .sem { color: var(--fg); }
.doc-view .sem-empty { color: var(--muted); font-style: italic; font-size: 0.9em; }

.doc-view h1.node-heading { margin: 0 0 12px; }
.doc-view h2.node-heading { margin: 18px 0 6px; padding-top: 8px; border-top: 1px solid var(--border); }
.doc-view h1.node-heading:first-child,
.doc-view h2.node-heading:first-child { border-top: none; padding-top: 0; margin-top: 0; }

.doc-view h1.node-heading .sem { font-size: 1.35rem; font-weight: 600; letter-spacing: -0.015em; }
.doc-view h2.node-heading .sem { font-size: 1.1rem; font-weight: 600; }
.doc-view h3.node-heading .sem { font-size: 0.98rem; font-weight: 600; color: var(--accent); }
.doc-view h4.node-heading .sem { font-size: 0.92rem; font-weight: 600; color: var(--accent); }
.doc-view h5.node-heading .sem,
.doc-view h6.node-heading .sem { font-size: 0.88rem; font-weight: 600; color: var(--muted); }

.doc-view .children {
  margin-left: 14px;
  padding-left: 14px;
  border-left: 1px dotted var(--border-strong);
}

.doc-view .hidden {
  background: var(--hidden-bg);
  border: 1px solid var(--border-strong);
  border-radius: 4px;
  padding: 10px 14px;
  margin: 6px 0 10px;
  font-size: 0.92em;
}

.doc-view .hidden-label {
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--star);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: 6px;
  display: flex;
  align-items: center;
  gap: 6px;
}
.doc-view .hidden-label::before { content: "✦"; color: var(--star); }

.doc-view .hidden-entry {
  display: flex;
  gap: 10px;
  margin: 3px 0;
  align-items: baseline;
  flex-wrap: wrap;
}
.doc-view .hidden-entry .addr { background: var(--panel); }

.doc-view .ref {
  font-family: var(--mono);
  font-size: 0.9em;
  color: var(--star);
  word-break: break-all;
}
.doc-view .ref::before { content: "→ "; color: var(--muted); }
.doc-view .ref-addr { color: var(--accent); }

.doc-view a.ref-link {
  font-family: var(--mono);
  font-size: 0.9em;
  color: var(--star);
  text-decoration: none;
  border-bottom: 1px dashed var(--star);
  cursor: pointer;
  padding: 0 2px;
}
.doc-view a.ref-link::before { content: "→ "; color: var(--muted); border: none; }
.doc-view a.ref-link:hover { background: var(--panel-2); }
.doc-view a.ref-link.broken { color: var(--faint); border-bottom-color: var(--faint); cursor: not-allowed; }
.doc-view a.ref-link.broken::after { content: " (missing)"; font-size: 0.85em; font-style: italic; }

.doc-view .inline-block {
  margin-top: 6px;
  border-left: 2px solid var(--star);
  padding-left: 10px;
}

/* ── Dir view ───────────────────────────────── */

.dir-view {
  padding: 8px 0;
  font-family: var(--mono);
  font-size: 0.8rem;
  line-height: 1.5;
}

.dir-row {
  display: flex;
  gap: 10px;
  padding: 4px 14px 4px 0;
  cursor: pointer;
  border-bottom: 1px solid transparent;
  transition: background 0.08s, border-color 0.08s;
  align-items: baseline;
}

.dir-row:hover {
  background: var(--panel-2);
  border-bottom-color: var(--border);
}

.dir-row.root {
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  font-weight: 500;
}

.dir-row.hidden {
  background: var(--hidden-bg);
  border-bottom: 1px solid transparent;
}

.dir-row.hidden:hover {
  background: var(--panel-2);
}

.dir-addr {
  color: var(--muted);
  font-size: 0.72rem;
  min-width: 70px;
  flex-shrink: 0;
  padding-top: 1px;
}

.dir-addr.star { color: var(--star); }

.dir-text {
  color: var(--fg);
  flex: 1;
  font-family: var(--serif);
  font-size: 0.88rem;
  overflow: hidden;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  word-break: break-word;
}

.dir-text.empty { color: var(--muted); font-style: italic; }
.dir-text.leaf { color: var(--fg); }
.dir-text.ref {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--star);
}
.dir-text.ref.jump { cursor: pointer; border-bottom: 1px dashed var(--star); }
.dir-text.ref.jump:hover { background: var(--panel-2); }
.dir-text.ref.broken { color: var(--faint); }

/* Dir breadcrumb (in view-controls) */
.dir-breadcrumb {
  display: inline-flex;
  gap: 2px;
  align-items: center;
  font-family: var(--mono);
  font-size: 0.72rem;
}

.dir-breadcrumb .bc-piece {
  color: var(--fg);
  cursor: pointer;
  padding: 1px 3px;
  border-radius: 2px;
}

.dir-breadcrumb .bc-piece:first-child { color: var(--branch); padding: 1px 4px; }
.dir-breadcrumb .bc-piece:hover { background: var(--panel-2); }
.dir-breadcrumb .bc-piece.star { color: var(--star); }
.dir-breadcrumb .bc-sep { color: var(--muted); padding: 0 1px; }
.dir-breadcrumb .bc-number { display: inline-flex; gap: 0; align-items: center; margin-left: 2px; }

/* ── Column view ────────────────────────────── */

.col-view { display: flex; flex-direction: column; height: 100%; }

.col-path {
  font-family: var(--mono);
  font-size: 0.72rem;
  padding: 8px 14px;
  border-bottom: 1px solid var(--border);
  color: var(--muted);
  background: var(--panel);
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.col-path .path-piece {
  color: var(--fg);
  cursor: pointer;
  padding: 1px 3px;
  border-radius: 2px;
}
.col-path .path-piece:hover { background: var(--panel-2); }
.col-path .path-piece.star { color: var(--star); }
.col-path .path-sep { color: var(--muted); padding: 0 1px; }
.col-path .path-root {
  color: var(--branch);
  cursor: pointer;
  padding: 1px 4px;
  border-radius: 2px;
}
.col-path .path-root:hover { background: var(--panel-2); }
.col-path .path-number { display: inline-flex; gap: 0; align-items: center; margin-left: 2px; }

.columns-wrap {
  flex: 1;
  display: flex;
  overflow-x: auto;
  overflow-y: hidden;
  min-height: 0;
}

.column {
  flex-shrink: 0;
  width: 260px;
  border-right: 1px solid var(--border);
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  background: var(--bg);
}

.column.star-col { background: var(--hidden-bg); border-right-color: var(--border-strong); }

.col-header {
  font-family: var(--mono);
  font-size: 0.6rem;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 8px 12px;
  border-bottom: 1px solid var(--border);
  background: var(--panel);
  position: sticky;
  top: 0;
}
.column.star-col .col-header { color: var(--star); }

.cell {
  padding: 10px 12px;
  border-bottom: 1px solid var(--border);
  cursor: pointer;
  display: flex;
  gap: 8px;
  align-items: flex-start;
  font-size: 0.78rem;
  transition: background 0.08s;
}
.cell:hover { background: var(--panel-2); }
.cell.in-path { background: var(--panel-2); }
.cell.selected { background: var(--accent); color: var(--bg); }
.cell.selected .cell-digit { color: var(--bg); opacity: 0.75; }
.cell.selected .marker { color: var(--bg); }
.cell.selected:hover { background: var(--accent); }
.cell.dimmed { opacity: 0.35; }
.cell.highlight { box-shadow: inset 3px 0 0 var(--accent); }
.cell.highlight-ring { box-shadow: inset 3px 0 0 var(--muted); }

.cell-digit {
  font-family: var(--mono);
  font-size: 0.68rem;
  color: var(--branch);
  font-weight: 600;
  min-width: 16px;
  flex-shrink: 0;
  padding-top: 2px;
}

.cell-body { flex: 1; min-width: 0; }

.cell-text {
  line-height: 1.45;
  overflow: hidden;
  display: -webkit-box;
  -webkit-line-clamp: 4;
  -webkit-box-orient: vertical;
  word-break: break-word;
}

.cell-text.empty { color: var(--muted); font-style: italic; font-size: 0.92em; }
.cell.addr-ref .cell-text { color: var(--accent); font-family: var(--mono); }
.cell.ref-leaf .cell-text { font-style: italic; }

.cell-markers {
  display: flex;
  gap: 6px;
  margin-top: 5px;
  font-family: var(--mono);
  font-size: 0.58rem;
  color: var(--muted);
  flex-wrap: wrap;
}

.marker { display: inline-flex; align-items: center; gap: 2px; }
.marker-branch { color: var(--branch); }
.marker-hidden {
  color: var(--star);
  cursor: pointer;
  padding: 1px 5px;
  border-radius: 2px;
  border: 1px solid var(--star);
}
.marker-hidden:hover { background: var(--star); color: var(--bg); }

.marker-jump {
  color: var(--star);
  cursor: pointer;
  padding: 1px 5px;
  border-radius: 2px;
  border: 1px solid var(--star);
}
.marker-jump:hover { background: var(--star); color: var(--bg); }
.marker-broken {
  color: var(--faint);
  border: 1px dashed var(--faint);
  padding: 1px 5px;
  border-radius: 2px;
}

.cell.selected .marker-hidden,
.cell.selected .marker-jump { border-color: var(--bg); color: var(--bg); }
.cell.selected .marker-hidden:hover,
.cell.selected .marker-jump:hover { background: var(--bg); color: var(--accent); }

.col-edit {
  width: 100%;
  background: var(--bg);
  border: 1px solid var(--accent);
  color: var(--fg);
  font-family: inherit;
  font-size: 0.78rem;
  padding: 6px;
  border-radius: 3px;
  resize: vertical;
  outline: none;
  line-height: 1.5;
  min-height: 70px;
}

.col-empty {
  padding: 16px;
  color: var(--muted);
  font-style: italic;
  font-size: 0.72rem;
}

/* ── Status bar ─────────────────────────────── */

#status-bar {
  grid-column: 1 / -1;
  padding: 6px 14px;
  border-top: 1px solid var(--border);
  background: var(--panel);
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 0.68rem;
  color: var(--muted);
}

#status-block { color: var(--accent); font-weight: 500; }
#status-addr { font-family: var(--mono); color: var(--branch); }

/* ── Scrollbar ──────────────────────────────── */

::-webkit-scrollbar { width: 4px; height: 4px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-strong); border-radius: 2px; }