:root {
  color-scheme: dark;
  --bg: #0e1117;
  --bg-panel: #161b22;
  --bg-surface: #0d1117;
  --bg-input: #0a0e14;
  --border: rgba(139, 148, 158, 0.2);
  --border-focus: rgba(110, 140, 255, 0.5);
  --text: #e6edf3;
  --text-muted: #8b949e;
  --text-dim: #6e7681;
  --accent: #4ecdc4;
  --accent-strong: #6e8cff;
  --success: #4ecdc4;
  --error: #ff8a7a;
  --neutral: #8da1c4;
  --radius: 8px;
  --radius-lg: 12px;
  --mono: "IBM Plex Mono", "Fira Code", Consolas, monospace;
  --sans: "Space Grotesk", "Segoe UI", sans-serif;
}

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

html, body {
  height: 100%;
  overflow: hidden;
}

body {
  font-family: var(--sans);
  font-size: 14px;
  color: var(--text);
  background: var(--bg);
}

/* ── App Shell ── */
.app-shell {
  height: 100vh;
  display: flex;
  flex-direction: column;
  gap: 0;
  overflow: hidden;
}

/* ── App Bar ── */
.app-bar {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 16px;
  background: var(--bg-panel);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.app-bar-title {
  font-size: 15px;
  font-weight: 700;
  color: var(--accent);
  white-space: nowrap;
  margin-right: 8px;
}

.app-bar-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text-muted);
  text-decoration: none;
  font-size: 12px;
  line-height: 1;
  white-space: nowrap;
  background: rgba(255, 255, 255, 0.02);
  transition: color 0.15s, border-color 0.15s, background 0.15s;
}

.app-bar-link svg {
  width: 14px;
  height: 14px;
  flex: 0 0 auto;
}

.app-bar-link:hover {
  color: var(--text);
  border-color: var(--border-focus);
  background: rgba(255, 255, 255, 0.05);
}

.app-bar-controls {
  display: flex;
  align-items: center;
  gap: 10px;
  flex: 1;
  min-width: 0;
  flex-wrap: wrap;
}

.control-group {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  color: var(--text-muted);
  white-space: nowrap;
}

.control-group select,
.control-group input[type="number"] {
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font: inherit;
  font-size: 13px;
  padding: 5px 8px;
  outline: none;
  transition: border-color 0.15s;
}

.control-group select:focus,
.control-group input[type="number"]:focus {
  border-color: var(--border-focus);
}

.control-group select {
  max-width: 200px;
  min-width: 120px;
}

.control-group input[type="number"] {
  width: 70px;
}

.control-toggle {
  cursor: pointer;
  gap: 5px;
}

.control-toggle input[type="checkbox"] {
  accent-color: var(--accent-strong);
  margin: 0;
  width: 14px;
  height: 14px;
}

/* ── Status ── */
.status-chip {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: var(--radius);
  background: var(--bg-surface);
  border: 1px solid var(--border);
  font-size: 12px;
  margin-left: auto;
  max-width: 300px;
  min-width: 0;
}

.status-chip[data-tone="neutral"] { color: var(--neutral); }
.status-chip[data-tone="success"] { color: var(--success); }
.status-chip[data-tone="error"] { color: var(--error); }

.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: currentColor;
  flex-shrink: 0;
}

#status {
  margin: 0;
  font-size: 12px;
  line-height: 1.4;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ── Render Button ── */
#render-btn {
  flex-shrink: 0;
  border: none;
  border-radius: var(--radius);
  padding: 7px 16px;
  background: var(--accent);
  color: #0e1117;
  font: inherit;
  font-size: 13px;
  font-weight: 700;
  cursor: pointer;
  transition: background 0.15s, opacity 0.15s;
  white-space: nowrap;
}

#render-btn:hover:not(:disabled) {
  background: #5de0d7;
}

#render-btn:disabled {
  cursor: wait;
  opacity: 0.7;
}

.button-label { display: inline; }
.button-subtle { display: none; }

/* ── Workspace ── */
.workspace {
  flex: 1;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: var(--border);
  min-height: 0;
  overflow: hidden;
}

/* ── Panels ── */
.panel {
  background: var(--bg-panel);
  display: flex;
  flex-direction: column;
  min-height: 0;
  overflow: hidden;
}

/* ── Tab Container ── */
.tab-container {
  display: flex;
  flex-direction: column;
  height: 100%;
  min-height: 0;
  overflow: hidden;
}

.tab-buttons {
  display: flex;
  gap: 2px;
  padding: 6px 8px;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.tab-button {
  border: none;
  border-radius: 6px;
  background: transparent;
  color: var(--text-dim);
  font: inherit;
  font-size: 12px;
  font-weight: 500;
  padding: 5px 12px;
  cursor: pointer;
  transition: color 0.15s, background 0.15s;
}

.tab-button:hover {
  color: var(--text-muted);
  background: rgba(255, 255, 255, 0.04);
}

.tab-button.active {
  color: var(--text);
  background: rgba(110, 140, 255, 0.15);
}

/* ── Tab Content ── */
.tab-content {
  flex: 1;
  position: relative;
  min-height: 0;
  overflow: hidden;
}

.tab-pane {
  display: none;
  position: absolute;
  inset: 0;
}

.tab-pane.active {
  display: flex;
  flex-direction: column;
}

/* ── Editor Panel Overrides ── */
.editor-panel .tab-content {
  position: relative;
}

.editor-panel .tab-pane {
  padding: 0;
}

.editor-section {
  display: flex;
  flex-direction: column;
  height: 100%;
  min-height: 0;
}

textarea {
  flex: 1;
  width: 100%;
  min-height: 0;
  resize: none;
  border: none;
  background: var(--bg-surface);
  color: var(--text);
  padding: 12px;
  font-family: var(--mono);
  font-size: 13px;
  line-height: 1.6;
  outline: none;
}

/* ── CodeMirror ── */
.editor-panel .CodeMirror {
  flex: 1;
  min-height: 0;
  height: 100%;
  border: none;
  border-radius: 0;
  background: var(--bg-surface);
  color: var(--text);
  font-family: var(--mono);
  font-size: 13px;
}

.editor-panel .CodeMirror-scroll {
  padding: 8px 0;
}

.editor-panel .cm-s-darcula.CodeMirror,
.editor-panel .cm-s-darcula .CodeMirror-gutters {
  background: var(--bg-surface);
}

.editor-panel .cm-s-darcula .CodeMirror-gutters {
  border-right: 1px solid var(--border);
}

.editor-panel .cm-s-darcula .CodeMirror-linenumber {
  color: var(--text-dim);
}

.editor-panel .cm-s-darcula .CodeMirror-cursor {
  border-left: 2px solid var(--accent);
}

.editor-panel .cm-s-darcula .CodeMirror-selected {
  background: rgba(110, 140, 255, 0.18) !important;
}

.editor-panel .cm-s-darcula .CodeMirror-activeline-background {
  background: rgba(110, 140, 255, 0.06) !important;
}

/* ── Preview Panel ── */
.preview-panel .tab-pane {
  padding: 0;
}

.preview-frame {
  position: relative;
  height: 100%;
  width: 100%;
  overflow: hidden;
  background: var(--bg-surface);
}

#pdf-viewer,
#html-viewer {
  width: 100%;
  height: 100%;
  border: none;
  background: #eef1f5;
}

.preview-empty {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  gap: 6px;
  padding: 24px;
  color: var(--text-dim);
  font-size: 14px;
}

.preview-frame.has-document .preview-empty {
  display: none;
}

/* ── CKEditor ── */
.ck.ck-editor {
  height: 100%;
}

.ck.ck-editor__main,
.ck.ck-content {
  min-height: 200px;
}

/* ── Debug Panel ── */
.debug-panel {
  border-top: 1px solid var(--border);
  background: var(--bg-panel);
  flex-shrink: 0;
}

.debug-panel summary {
  list-style: none;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  cursor: pointer;
  padding: 8px 16px;
  font-size: 12px;
  font-weight: 500;
  color: var(--text-muted);
  user-select: none;
}

.debug-panel summary::-webkit-details-marker {
  display: none;
}

.debug-panel summary::after {
  content: "▸";
  font-size: 11px;
  transition: transform 0.15s;
}

.debug-panel[open] summary::after {
  transform: rotate(90deg);
}

.debug-controls {
  padding: 8px 16px 12px;
}

.debug-grid {
  display: grid;
  grid-template-columns: 180px 1fr;
  gap: 10px;
}

.debug-card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 10px;
}

.debug-card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  margin-bottom: 8px;
  font-size: 12px;
  color: var(--text-muted);
}

.debug-button-group {
  display: inline-flex;
  gap: 4px;
}

.debug-button-group button {
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--bg-input);
  color: var(--text-muted);
  font: inherit;
  font-size: 11px;
  padding: 3px 8px;
  cursor: pointer;
  transition: color 0.15s, border-color 0.15s;
}

.debug-button-group button:hover {
  color: var(--text);
  border-color: var(--border-focus);
}

.field {
  display: flex;
  flex-direction: column;
  gap: 4px;
  color: var(--text-muted);
  font-size: 12px;
}

.field select {
  width: 100%;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--text);
  font: inherit;
  font-size: 12px;
  padding: 5px 8px;
  outline: none;
}

.field select:focus {
  border-color: var(--border-focus);
}

.checkbox-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  gap: 4px;
}

.checkbox-grid label {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 6px;
  border-radius: 6px;
  color: var(--text-muted);
  font-size: 12px;
  cursor: pointer;
}

.checkbox-grid label:hover {
  background: rgba(255, 255, 255, 0.03);
}

.checkbox-grid input {
  accent-color: var(--accent-strong);
}

/* ── Utility ── */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ── Responsive ── */
@media (max-width: 900px) {
  html, body { overflow: auto; }
  .app-shell { height: auto; min-height: 100vh; }
  .app-bar { flex-wrap: wrap; }
  .app-bar-controls { flex-wrap: wrap; }
  .workspace {
    grid-template-columns: 1fr;
    gap: 0;
    overflow: visible;
  }
  .panel { min-height: 50vh; }
  .debug-grid { grid-template-columns: 1fr; }
}