:root {
  --bg-primary: #f1f5f9;
  --bg-secondary: #ffffff;
  --bg-toolbar: #0f172a;
  --bg-format-bar: #1e293b;
  --text-primary: #334155;
  --text-secondary: #64748b;
  --text-toolbar: #cbd5e1;
  --text-toolbar-hover: #ffffff;
  --accent: #3b82f6;
  --accent-hover: #2563eb;
  --accent-light: #dbeafe;
  --border: #e2e8f0;
  --border-dark: #cbd5e1;
  --success: #10b981;
  --warning: #f59e0b;
  --danger: #ef4444;
  --info: #06b6d4;
  --pane-header: #f8fafc;
  --shadow: 0 1px 3px rgba(0,0,0,0.1);
  --shadow-lg: 0 10px 25px rgba(0,0,0,0.15);
  --radius: 6px;
  --radius-lg: 10px;
}
body.dark-theme {
  --bg-primary: #0f172a;
  --bg-secondary: #1e293b;
  --bg-toolbar: #020617;
  --bg-format-bar: #0f172a;
  --text-primary: #e2e8f0;
  --text-secondary: #94a3b8;
  --text-toolbar: #94a3b8;
  --border: #334155;
  --border-dark: #475569;
  --pane-header: #1e293b;
  --shadow: 0 1px 3px rgba(0,0,0,0.3);
  --shadow-lg: 0 10px 25px rgba(0,0,0,0.4);
  --accent-light: #1e3a5f;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  height: 100vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

/* Toolbar */
.toolbar {
  background: var(--bg-toolbar);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 12px;
  height: 48px;
  gap: 8px;
  z-index: 100;
  flex-shrink: 0;
}
.toolbar-left, .toolbar-center, .toolbar-right { display: flex; align-items: center; gap: 4px; }
.logo {
  display: flex;
  align-items: center;
  gap: 8px;
  color: #60a5fa;
  font-weight: 700;
  font-size: 15px;
  margin-right: 16px;
  user-select: none;
}
.logo i { font-size: 18px; }
.toolbar-group {
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 0 4px;
  border-right: 1px solid #334155;
  margin-right: 4px;
}
.toolbar-group:last-child { border-right: none; margin-right: 0; }
.toolbar button, .toolbar .dropdown > button {
  background: transparent;
  border: none;
  color: var(--text-toolbar);
  padding: 6px 10px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 13px;
  display: flex;
  align-items: center;
  gap: 5px;
  transition: all 0.15s;
  white-space: nowrap;
}
.toolbar button:hover { background: rgba(255,255,255,0.1); color: var(--text-toolbar-hover); }
.toolbar .btn-clear-all { color: #fca5a5; }
.toolbar .btn-clear-all:hover { background: #dc2626; color: #fff; }
.btn-text { font-size: 12px; }
.dropdown { position: relative; }
.dropdown-content {
  display: none;
  position: absolute;
  top: 100%;
  left: 0;
  background: var(--bg-secondary);
  min-width: 200px;
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border);
  z-index: 200;
  overflow: hidden;
  margin-top: 4px;
}
.dropdown-content.show { display: block; }
.dropdown-content a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 16px;
  color: var(--text-primary);
  text-decoration: none;
  font-size: 13px;
  cursor: pointer;
  transition: background 0.15s;
}
.dropdown-content a:hover { background: var(--accent-light); color: var(--accent); }
.dropdown-content a i { width: 16px; text-align: center; color: var(--text-secondary); }
.dropdown-content a:hover i { color: var(--accent); }
.dropdown-content hr { border: none; border-top: 1px solid var(--border); margin: 4px 0; }

/* Format bar */
.format-bar {
  background: var(--bg-format-bar);
  display: flex;
  align-items: center;
  padding: 4px 12px;
  gap: 2px;
  flex-wrap: wrap;
  border-bottom: 1px solid rgba(255,255,255,0.05);
  flex-shrink: 0;
}
.format-bar button {
  background: transparent;
  border: 1px solid transparent;
  color: #94a3b8;
  width: 32px;
  height: 28px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.15s;
  font-family: inherit;
}
.format-bar button:hover { background: rgba(255,255,255,0.1); color: #e2e8f0; border-color: rgba(255,255,255,0.1); }
.format-bar button i { font-size: 13px; }
.format-separator { width: 1px; height: 20px; background: #334155; margin: 0 6px; flex-shrink: 0; }
.format-group { display: flex; align-items: center; gap: 1px; }

/* Find & Replace */
.find-replace-bar {
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border);
  padding: 8px 16px;
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
  flex-shrink: 0;
}
.find-replace-inputs { display: flex; gap: 8px; flex: 1; min-width: 300px; }
.find-input-group {
  display: flex;
  align-items: center;
  gap: 6px;
  background: var(--bg-primary);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 4px 10px;
  flex: 1;
}
.find-input-group i { color: var(--text-secondary); font-size: 12px; }
.find-input-group input {
  border: none;
  background: transparent;
  color: var(--text-primary);
  font-size: 13px;
  outline: none;
  flex: 1;
  min-width: 80px;
}
.find-count { font-size: 11px; color: var(--text-secondary); white-space: nowrap; }
.find-replace-actions { display: flex; align-items: center; gap: 4px; }
.find-replace-actions button {
  background: var(--bg-primary);
  border: 1px solid var(--border);
  color: var(--text-primary);
  padding: 4px 10px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 12px;
  transition: all 0.15s;
}
.find-replace-actions button:hover { border-color: var(--accent); color: var(--accent); }
.find-replace-actions .close-btn { border: none; background: transparent; padding: 4px 6px; }
.checkbox-label { display: flex; align-items: center; gap: 4px; font-size: 12px; color: var(--text-secondary); cursor: pointer; }
.checkbox-label input { cursor: pointer; }

/* Main content */
.main-content {
  display: flex;
  flex: 1;
  overflow: hidden;
  min-height: 0;
}
.editor-pane, .preview-pane {
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.editor-pane { flex: 1 1 50%; }
.preview-pane { flex: 1 1 50%; }
.pane-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6px 12px;
  background: var(--pane-header);
  border-bottom: 1px solid var(--border);
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  flex-shrink: 0;
}
.pane-header span { display: flex; align-items: center; gap: 6px; }
.pane-header button {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 2px 6px;
  border-radius: 3px;
  font-size: 12px;
}
.pane-header button:hover { background: var(--border); color: var(--text-primary); }
.CodeMirror {
  flex: 1;
  height: auto !important;
  font-size: 14px;
  line-height: 1.6;
  font-family: 'Cascadia Code', 'Fira Code', 'JetBrains Mono', 'Consolas', monospace;
  border: none;
}
body:not(.dark-theme) .CodeMirror {
  background: var(--bg-secondary);
}
#previewFrame {
  flex: 1;
  border: none;
  background: #ffffff;
  width: 100%;
}
.resizer {
  width: 5px;
  background: var(--border);
  cursor: col-resize;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: background 0.15s;
  position: relative;
}
.resizer:hover, body.resizing .resizer { background: var(--accent); }
.resizer-handle {
  width: 3px;
  height: 30px;
  border-radius: 2px;
  background: var(--text-secondary);
  opacity: 0.4;
}
.resizer:hover .resizer-handle { opacity: 0; }
body.resizing { cursor: col-resize; user-select: none; }
body.resizing iframe { pointer-events: none; }

/* Status bar */
.status-bar {
  background: var(--accent);
  color: #ffffff;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  height: 24px;
  font-size: 11px;
  flex-shrink: 0;
}
.status-left, .status-right { display: flex; align-items: center; gap: 16px; }

/* Clean panel */
.clean-panel-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  z-index: 300;
}
.clean-panel-overlay.show { display: block; }
.clean-panel {
  position: fixed;
  top: 0;
  right: -420px;
  width: 400px;
  height: 100vh;
  background: var(--bg-secondary);
  z-index: 301;
  display: flex;
  flex-direction: column;
  box-shadow: -5px 0 25px rgba(0,0,0,0.2);
  transition: right 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}
.clean-panel.show { right: 0; }
.clean-panel-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}
.clean-panel-header h3 { font-size: 16px; display: flex; align-items: center; gap: 8px; }
.clean-panel-header button {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 18px;
  padding: 4px;
  border-radius: 4px;
}
.clean-panel-header button:hover { background: var(--border); }
.clean-panel-body {
  flex: 1;
  overflow-y: auto;
  padding: 16px 20px;
}
.clean-section {
  margin-bottom: 20px;
}
.clean-section h4 {
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  gap: 6px;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.clean-section label {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 8px;
  border-radius: 4px;
  cursor: pointer;
  font-size: 13px;
  transition: background 0.15s;
}
.clean-section label:hover { background: var(--accent-light); }
.clean-section label code {
  background: var(--bg-primary);
  padding: 1px 5px;
  border-radius: 3px;
  font-size: 12px;
  color: var(--danger);
}
.clean-section input[type="checkbox"] { accent-color: var(--accent); cursor: pointer; flex-shrink: 0; }
.custom-input-group {
  display: flex;
  gap: 6px;
  margin-top: 8px;
  padding: 0 8px;
}
.custom-input-group input, .custom-input-group select {
  padding: 5px 8px;
  border: 1px solid var(--border);
  border-radius: 4px;
  font-size: 12px;
  background: var(--bg-primary);
  color: var(--text-primary);
  outline: none;
}
.custom-input-group input { flex: 1; }
.custom-input-group input:focus, .custom-input-group select:focus { border-color: var(--accent); }
.clean-panel-footer {
  padding: 16px 20px;
  border-top: 1px solid var(--border);
  flex-shrink: 0;
}
.clean-panel-actions {
  display: flex;
  gap: 8px;
  margin-bottom: 12px;
}
.btn-outline {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-primary);
  padding: 6px 14px;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 12px;
  transition: all 0.15s;
  flex: 1;
}
.btn-outline:hover { border-color: var(--accent); color: var(--accent); }
.btn-primary {
  background: var(--accent);
  border: none;
  color: #ffffff;
  padding: 10px 20px;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: all 0.15s;
}
.btn-primary:hover { background: var(--accent-hover); }

/* Notifications */
.notification {
  position: fixed;
  top: 60px;
  right: 20px;
  padding: 12px 20px;
  border-radius: var(--radius);
  font-size: 13px;
  font-weight: 500;
  z-index: 500;
  display: flex;
  align-items: center;
  gap: 8px;
  transform: translateX(120%);
  transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  box-shadow: var(--shadow-lg);
  color: #ffffff;
}
.notification.show { transform: translateX(0); }
.notification-success { background: var(--success); }
.notification-error { background: var(--danger); }
.notification-warning { background: var(--warning); color: #1e293b; }
.notification-info { background: var(--info); }

/* Scrollbar */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border-dark); border-radius: 4px; }
::-webkit-scrollbar-thumb:hover { background: var(--text-secondary); }

/* Hidden pane */
.pane-hidden { display: none !important; }
.pane-full { flex: 1 1 100% !important; }
.resizer-hidden { display: none !important; }

/* Color picker trigger */
#colorPicker { position: absolute; visibility: hidden; width: 0; height: 0; }

/* Modal dialogs */
.modal-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 400;
  align-items: center;
  justify-content: center;
}
.modal-overlay.show { display: flex; }
.modal {
  background: var(--bg-secondary);
  border-radius: var(--radius-lg);
  width: 460px;
  max-width: 95vw;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: 0 20px 60px rgba(0,0,0,0.3);
  border: 1px solid var(--border);
}
.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
}
.modal-header h3 { font-size: 15px; display: flex; align-items: center; gap: 8px; }
.modal-header button {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 18px;
  padding: 4px;
  border-radius: 4px;
}
.modal-header button:hover { background: var(--border); }
.modal-body { padding: 16px 20px; }
.modal-field { margin-bottom: 14px; }
.modal-field label {
  display: block;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 5px;
  text-transform: uppercase;
  letter-spacing: 0.3px;
}
.modal-field input[type="text"],
.modal-field input[type="number"],
.modal-field input[type="url"],
.modal-field select {
  width: 100%;
  padding: 8px 10px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  font-size: 13px;
  background: var(--bg-primary);
  color: var(--text-primary);
  outline: none;
  font-family: inherit;
}
.modal-field input:focus, .modal-field select:focus { border-color: var(--accent); }
.modal-row { display: flex; gap: 10px; }
.modal-row .modal-field { flex: 1; min-width: 0; }
.modal-check {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 0;
  font-size: 13px;
  cursor: pointer;
}
.modal-check input { accent-color: var(--accent); cursor: pointer; }
.modal-footer {
  padding: 12px 20px 16px;
  display: flex;
  gap: 8px;
  justify-content: flex-end;
}
.modal-footer .btn-cancel {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text-primary);
  padding: 8px 18px;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 13px;
}
.modal-footer .btn-cancel:hover { border-color: var(--text-secondary); }
.modal-footer .btn-insert {
  background: var(--accent);
  border: none;
  color: #fff;
  padding: 8px 20px;
  border-radius: var(--radius);
  cursor: pointer;
  font-size: 13px;
  font-weight: 600;
  display: flex;
  align-items: center;
  gap: 6px;
}
.modal-footer .btn-insert:hover { background: var(--accent-hover); }
.modal-size-group { display: flex; gap: 6px; align-items: center; }
.modal-size-group input[type="number"] { width: 80px; flex: none; }
.modal-size-group select { width: 70px; flex: none; }
.modal-hint { font-size: 11px; color: var(--text-secondary); margin-top: 3px; }
.modal-field-hidden { display: none; }

@media (max-width: 768px) {
  .btn-text { display: none; }
  .toolbar-group { padding: 0 2px; margin-right: 2px; }
  .format-bar { padding: 4px 6px; }
  .clean-panel { width: 100%; right: -100%; }
}