.tool-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 24px;
}
.tool-header {
  text-align: center;
  margin-bottom: 20px;
}
.tool-header h1 {
  font-size: 32px;
  font-weight: 800;
  color: var(--color-heading);
  margin-bottom: 8px;
}
.tool-header .tool-desc {
  font-size: 16px;
  color: var(--color-muted);
  max-width: 700px;
  margin: 0 auto;
  line-height: 1.6;
}

/* ========== Mode Tabs ========== */
.mode-tabs {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin-bottom: 16px;
}
.mode-tab {
  padding: 10px 24px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-bg-card);
  color: var(--color-text);
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
  transition: all 0.2s;
}
.mode-tab:hover {
  border-color: var(--color-primary);
  color: var(--color-primary);
}
.mode-tab.active {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}
.mode-tab.auto-tab {
  border-color: #f59e0b;
  color: #f59e0b;
}
.mode-tab.auto-tab.active {
  background: #f59e0b;
  color: #fff;
  border-color: #f59e0b;
}

/* ========== Options Bar ========== */
.options-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  align-items: center;
  justify-content: center;
  margin-bottom: 16px;
  padding: 12px 16px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 10px;
}
.options-bar label {
  font-size: 13px;
  font-weight: 600;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: 6px;
}
.options-bar select {
  padding: 5px 10px;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  font-size: 13px;
  background: #fff;
  color: var(--color-text);
  cursor: pointer;
}
.options-bar input[type="checkbox"] {
  width: 16px;
  height: 16px;
  cursor: pointer;
}
.options-bar .badge-sm {
  display: inline-block;
  background: var(--color-primary);
  color: #fff;
  font-size: 11px;
  font-weight: 700;
  padding: 2px 8px;
  border-radius: 10px;
  margin-left: 6px;
}

/* ========== Editor Area ========== */
.tool-editor {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  margin-bottom: 16px;
}
.editor-panel {
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  overflow: hidden;
}
.editor-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  background: var(--color-bg-card);
  border-bottom: 1px solid var(--color-border);
}
.editor-panel-header h3 {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-heading);
}
.editor-panel-header .panel-actions {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}
.panel-btn {
  padding: 5px 11px;
  font-size: 12px;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background: #fff;
  color: var(--color-text);
  cursor: pointer;
  transition: all 0.2s;
  white-space: nowrap;
}
.panel-btn:hover {
  background: var(--color-bg-hover);
  border-color: var(--color-primary);
}
.panel-btn.primary {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}
.panel-btn.primary:hover {
  opacity: 0.9;
}
.editor-panel textarea {
  width: 100%;
  height: 320px;
  padding: 16px;
  border: none;
  font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
  font-size: 14px;
  line-height: 1.6;
  resize: vertical;
  background: #1e1e2e;
  color: #cdd6f4;
  box-sizing: border-box;
}
.editor-panel textarea:focus {
  outline: none;
}
.editor-panel textarea.output-area {
  background: #1e1e2e;
  color: #cdd6f4;
}
.editor-panel textarea.output-area:disabled {
  opacity: 1;
  cursor: default;
}

/* ========== Quick Insert Bar ========== */
.quick-insert-bar {
  margin-bottom: 16px;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  overflow: hidden;
}
.quick-insert-header {
  display: flex;
  align-items: center;
  padding: 10px 16px;
  background: var(--color-bg-card);
  border-bottom: 1px solid var(--color-border);
  gap: 8px;
}
.quick-insert-header span {
  font-size: 13px;
  font-weight: 600;
  color: var(--color-heading);
}
.quick-insert-tabs {
  display: flex;
  gap: 4px;
  margin-left: auto;
}
.qi-tab {
  padding: 4px 12px;
  font-size: 12px;
  border: 1px solid var(--color-border);
  border-radius: 6px;
  background: #fff;
  color: var(--color-text);
  cursor: pointer;
  transition: all 0.2s;
}
.qi-tab.active {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}
.qi-tab:hover:not(.active) {
  border-color: var(--color-primary);
}
.quick-insert-body {
  padding: 12px 16px;
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  min-height: 40px;
}
.qi-btn {
  padding: 4px 10px;
  font-size: 13px;
  font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
  border: 1px solid var(--color-border);
  border-radius: 5px;
  background: #fff;
  color: var(--color-text);
  cursor: pointer;
  transition: all 0.2s;
}
.qi-btn:hover {
  background: var(--color-primary);
  color: #fff;
  border-color: var(--color-primary);
}
.qi-btn .qi-desc {
  font-size: 10px;
  color: var(--color-muted);
  margin-left: 4px;
  font-family: sans-serif;
}
.qi-btn:hover .qi-desc {
  color: rgba(255,255,255,0.7);
}

/* ========== Visual Preview ========== */
.preview-section {
  margin-bottom: 16px;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  overflow: hidden;
}
.preview-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  background: var(--color-bg-card);
  border-bottom: 1px solid var(--color-border);
}
.preview-header h3 {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-heading);
}
.preview-toggle {
  font-size: 12px;
  color: var(--color-primary);
  cursor: pointer;
  user-select: none;
}
.preview-body {
  padding: 20px;
  min-height: 60px;
  border: 2px dashed var(--color-border);
  margin: 12px;
  border-radius: 8px;
  background: #fff;
  word-break: break-word;
  line-height: 1.6;
  font-size: 14px;
}
.preview-body.hidden {
  display: none;
}
.preview-placeholder {
  color: var(--color-muted);
  font-size: 13px;
  text-align: center;
}

/* ========== Stats Bar ========== */
.stats-bar {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-bottom: 20px;
  padding: 10px 16px;
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 10px;
  justify-content: center;
}
.stat-item {
  font-size: 13px;
  color: var(--color-text);
  display: flex;
  align-items: center;
  gap: 4px;
}
.stat-item .stat-label {
  color: var(--color-muted);
  font-weight: 500;
}
.stat-item .stat-value {
  font-weight: 700;
  font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
}
.badge-ratio {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 10px;
  font-size: 12px;
  font-weight: 700;
  color: #fff;
}
.badge-ratio.shrink { background: #22c55e; }
.badge-ratio.grow { background: #3b82f6; }
.badge-ratio.unchanged { background: #f59e0b; }

/* ========== Type Mode Badge ========== */
.mode-badge {
  display: inline-block;
  padding: 3px 10px;
  border-radius: 6px;
  font-size: 12px;
  font-weight: 700;
  margin-left: 8px;
}
.mode-badge.encode { background: #dbeafe; color: #1d4ed8; }
.mode-badge.decode { background: #fef3c7; color: #b45309; }

/* ========== Entity Reference Table ========== */
.entity-ref-section {
  margin-bottom: 24px;
  background: #fff;
  border: 1px solid var(--color-border);
  border-radius: 12px;
  overflow: hidden;
}
.entity-ref-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  background: var(--color-bg-card);
  border-bottom: 1px solid var(--color-border);
  cursor: pointer;
  user-select: none;
}
.entity-ref-header h3 {
  font-size: 15px;
  font-weight: 600;
  color: var(--color-heading);
}
.entity-ref-header .ref-toggle {
  font-size: 13px;
  color: var(--color-primary);
  transition: transform 0.2s;
}
.entity-ref-header .ref-toggle.open {
  transform: rotate(180deg);
}
.entity-ref-body {
  padding: 0;
  max-height: 0;
  overflow: hidden;
  transition: max-height 0.3s ease;
}
.entity-ref-body.open {
  max-height: 3000px;
}
.entity-ref-category {
  padding: 0;
}
.entity-ref-category h4 {
  font-size: 13px;
  font-weight: 700;
  color: var(--color-heading);
  padding: 10px 16px;
  margin: 0;
  background: var(--color-bg-card);
  border-bottom: 1px solid var(--color-border);
  border-top: 1px solid var(--color-border);
}
.entity-ref-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(140px, 1fr));
  gap: 6px;
  padding: 12px 16px;
}
.entity-ref-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 5px 8px;
  border: 1px solid var(--color-border);
  border-radius: 5px;
  cursor: pointer;
  transition: all 0.15s;
  font-size: 13px;
}
.entity-ref-item:hover {
  border-color: var(--color-primary);
  background: var(--color-bg-active);
}
.entity-ref-item .ref-char {
  font-size: 16px;
  min-width: 20px;
  text-align: center;
}
.entity-ref-item .ref-code {
  font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
  font-size: 12px;
  color: var(--color-muted);
}

/* ========== Tool Info ========== */
.tool-info {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: 12px;
  padding: 24px;
  margin-bottom: 24px;
}
.tool-info h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-heading);
  margin-bottom: 12px;
}
.tool-info p {
  font-size: 14px;
  line-height: 1.7;
  color: var(--color-text);
  margin-bottom: 10px;
}
.tool-info ul {
  padding-left: 20px;
  margin-bottom: 10px;
}
.tool-info li {
  font-size: 14px;
  line-height: 1.7;
  color: var(--color-text);
  margin-bottom: 4px;
}
.tool-info code {
  background: #f3f4f6;
  padding: 2px 6px;
  border-radius: 4px;
  font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
  font-size: 13px;
  color: #e11d48;
}
.tool-info .info-table {
  width: 100%;
  border-collapse: collapse;
  margin: 12px 0;
  font-size: 14px;
}
.tool-info .info-table th,
.tool-info .info-table td {
  border: 1px solid var(--color-border);
  padding: 8px 12px;
  text-align: left;
}
.tool-info .info-table th {
  background: var(--color-primary);
  color: #fff;
  font-weight: 600;
}
.tool-info .info-table td {
  background: #fff;
  font-family: 'Consolas', 'Monaco', 'Courier New', monospace;
}

/* ========== Status Message ========== */
#statusMessage {
  margin-bottom: 16px;
}
.error-box, .success-box {
  padding: 12px 16px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  display: none;
}
.error-box {
  background: #fef2f2;
  color: #dc2626;
  border: 1px solid #fecaca;
}
.success-box {
  background: #f0fdf4;
  color: #16a34a;
  border: 1px solid #bbf7d0;
}

/* ========== Responsive ========== */
@media (max-width: 900px) {
  .tool-editor { grid-template-columns: 1fr; }
  .tool-container { padding: 16px; }
  .tool-header h1 { font-size: 24px; }
  .mode-tab { padding: 8px 16px; font-size: 13px; }
  .entity-ref-grid { grid-template-columns: repeat(auto-fill, minmax(120px, 1fr)); }
}
@media (max-width: 600px) {
  .tool-container { padding: 12px; }
  .tool-header h1 { font-size: 20px; }
  .editor-panel textarea { height: 200px; }
  .options-bar { flex-direction: column; align-items: stretch; }
  .mode-tabs { flex-wrap: wrap; }
  .entity-ref-grid { grid-template-columns: repeat(auto-fill, minmax(100px, 1fr)); }
  .quick-insert-tabs { flex-wrap: wrap; }
}