:root {
  --primary-color: #1e6bb8;
  --primary-hover: #155592;
  --primary-light: #e8f3fc;
  --success-color: #07c160;
  --warning-color: #faad14;
  --danger-color: #ff4d4f;
  
  --bg-app: #f7f9fa;
  --bg-surface: #ffffff;
  --bg-subtle: #f0f2f5;
  --border-color: #e2e8f0;
  --border-light: #edf2f7;
  
  --text-primary: #1e293b;
  --text-secondary: #64748b;
  --text-muted: #94a3b8;
  
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.08), 0 2px 4px -1px rgba(0, 0, 0, 0.04);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  
  --header-height: 52px;
  --toolbar-height: 40px;
  --statusbar-height: 28px;
  
  --transition-fast: 0.15s ease;
  --transition-normal: 0.25s ease;
  --font-family-system: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

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

body {
  font-family: var(--font-family-system);
  background-color: var(--bg-app);
  color: var(--text-primary);
  line-height: 1.5;
  overflow: hidden;
  height: 100vh;
  width: 100vw;
  user-select: none;
}

/* App Container */
.app-container {
  display: flex;
  flex-direction: column;
  height: 100vh;
  width: 100vw;
  overflow: hidden;
}

/* Top Navigation Header (mdnice style) */
.header-navbar {
  min-height: var(--header-height);
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  z-index: 50;
  flex-shrink: 0;
  box-shadow: 0 1px 3px rgba(0,0,0,0.02);
  overflow-x: auto;
  gap: 16px;
}
.header-navbar::-webkit-scrollbar {
  height: 3px;
}
.header-navbar::-webkit-scrollbar-thumb {
  background: #cbd5e1;
  border-radius: 2px;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 16px;
}

.brand-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 700;
  font-size: 15px;
  color: #1e293b;
  cursor: pointer;
  letter-spacing: -0.3px;
}

.brand-logo .logo-badge {
  background: linear-gradient(135deg, #07c160, #10b981);
  color: white;
  font-size: 11px;
  padding: 2px 7px;
  border-radius: 6px;
  font-weight: 600;
}

.header-nav-btn {
  background: transparent;
  border: 1px solid transparent;
  color: var(--text-secondary);
  padding: 5px 10px;
  font-size: 13px;
  border-radius: 6px;
  cursor: pointer;
  display: inline-flex;
  align-items: center;
  gap: 5px;
  transition: all var(--transition-fast);
}

.header-nav-btn:hover {
  background: var(--bg-subtle);
  color: var(--text-primary);
}

.header-center {
  display: flex;
  align-items: center;
  gap: 12px;
}

.select-group {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 12px;
  color: var(--text-secondary);
}

.custom-select {
  appearance: none;
  background: var(--bg-subtle) url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%2364748b' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E") no-repeat right 8px center;
  border: 1px solid var(--border-color);
  padding: 5px 26px 5px 10px;
  border-radius: 6px;
  font-size: 12px;
  color: var(--text-primary);
  cursor: pointer;
  outline: none;
  transition: border-color var(--transition-fast);
  font-weight: 500;
}

.custom-select:hover, .custom-select:focus {
  border-color: var(--primary-color);
}

.header-toggles {
  display: flex;
  align-items: center;
  gap: 12px;
  border-left: 1px solid var(--border-color);
  padding-left: 12px;
}

.toggle-label {
  display: flex;
  align-items: center;
  gap: 5px;
  font-size: 12px;
  color: var(--text-secondary);
  cursor: pointer;
}

.toggle-checkbox {
  width: 14px;
  height: 14px;
  cursor: pointer;
  accent-color: var(--primary-color);
}

.header-right {
  display: flex;
  align-items: center;
  gap: 12px;
}

.viewport-switch {
  display: flex;
  background: var(--bg-subtle);
  padding: 2px;
  border-radius: 6px;
  border: 1px solid var(--border-color);
}

.viewport-btn {
  background: transparent;
  border: none;
  padding: 4px 8px;
  font-size: 12px;
  color: var(--text-secondary);
  border-radius: 4px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 4px;
  transition: all var(--transition-fast);
}

.viewport-btn.active {
  background: var(--bg-surface);
  color: var(--text-primary);
  font-weight: 600;
  box-shadow: var(--shadow-sm);
}

.btn-darkmode {
  background: var(--bg-subtle);
  border: 1px solid var(--border-color);
  width: 32px;
  height: 32px;
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all var(--transition-fast);
}

.btn-darkmode:hover {
  background: var(--border-color);
  color: var(--text-primary);
}

.compliance-badge {
  display: flex;
  align-items: center;
  gap: 6px;
  background: #f0fdf4;
  border: 1px solid #bbf7d0;
  color: #15803d;
  padding: 4px 10px;
  border-radius: 20px;
  font-size: 11px;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition-fast);
}

.compliance-badge:hover {
  background: #dcfce7;
}

.compliance-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: #22c55e;
  box-shadow: 0 0 0 2px rgba(34, 197, 94, 0.2);
  animation: pulse-dot 2s infinite;
}

@keyframes pulse-dot {
  0% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(34, 197, 94, 0.4); }
  70% { transform: scale(1.05); box-shadow: 0 0 0 6px rgba(34, 197, 94, 0); }
  100% { transform: scale(0.95); box-shadow: 0 0 0 0 rgba(34, 197, 94, 0); }
}

.btn-copy-wechat {
  background: linear-gradient(135deg, #07c160, #059669);
  color: white;
  border: none;
  padding: 6px 16px;
  font-size: 13px;
  font-weight: 600;
  border-radius: 6px;
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 6px;
  box-shadow: 0 2px 6px rgba(7, 193, 96, 0.3);
  transition: all var(--transition-fast);
}

.btn-copy-wechat:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(7, 193, 96, 0.4);
}

.btn-copy-wechat:active {
  transform: translateY(0);
}

/* Secondary Toolbar (Markdown Formatter Toolbar) */
.toolbar-container {
  height: var(--toolbar-height);
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  padding: 0 14px;
  gap: 4px;
  z-index: 40;
  flex-shrink: 0;
  overflow-x: auto;
}

.toolbar-btn {
  background: transparent;
  border: none;
  width: 28px;
  height: 28px;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-secondary);
  font-size: 13px;
  font-weight: 600;
  transition: all var(--transition-fast);
  flex-shrink: 0;
}

.toolbar-btn:hover {
  background: var(--bg-subtle);
  color: var(--text-primary);
}

.toolbar-divider {
  width: 1px;
  height: 18px;
  background: var(--border-color);
  margin: 0 4px;
  flex-shrink: 0;
}

/* Main Split View Area */
.main-split-area {
  display: flex;
  flex: 1;
  height: calc(100vh - var(--header-height) - var(--toolbar-height) - var(--statusbar-height));
  position: relative;
  overflow: hidden;
  background: var(--bg-surface);
}

.editor-pane {
  width: 50%;
  height: 100%;
  display: flex;
  flex-direction: column;
  position: relative;
  background: var(--bg-surface);
  border-right: 1px solid var(--border-color);
  overflow: hidden;
}

.pane-resizer {
  width: 6px;
  height: 100%;
  background: transparent;
  cursor: col-resize;
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  transform: translateX(-50%);
  z-index: 30;
  transition: background var(--transition-fast);
}

.pane-resizer:hover, .pane-resizer.dragging {
  background: rgba(30, 107, 184, 0.4);
}

.preview-pane {
  flex: 1;
  height: 100%;
  display: flex;
  flex-direction: column;
  background: #f4f5f7;
  overflow: hidden;
  position: relative;
}

/* Status Bar */
.statusbar-container {
  height: var(--statusbar-height);
  background: var(--bg-surface);
  border-top: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  font-size: 11px;
  color: var(--text-secondary);
  z-index: 50;
  flex-shrink: 0;
}

.statusbar-left, .statusbar-right {
  display: flex;
  align-items: center;
  gap: 16px;
}

.status-item {
  display: flex;
  align-items: center;
  gap: 4px;
}

/* Toast Message */
.toast-container {
  position: fixed;
  top: 64px;
  left: 50%;
  transform: translateX(-50%) translateY(-20px);
  background: #1e293b;
  color: white;
  padding: 8px 18px;
  border-radius: 8px;
  font-size: 13px;
  font-weight: 500;
  display: flex;
  align-items: center;
  gap: 8px;
  box-shadow: var(--shadow-lg);
  opacity: 0;
  pointer-events: none;
  transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  z-index: 9999;
}

.toast-container.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.toast-icon {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

/* Modal Window */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  backdrop-filter: blur(2px);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 999;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition-normal);
}

.modal-overlay.active {
  opacity: 1;
  pointer-events: auto;
}

.modal-dialog {
  background: var(--bg-surface);
  width: 90%;
  max-width: 520px;
  border-radius: 12px;
  box-shadow: var(--shadow-xl);
  overflow: hidden;
  transform: scale(0.95);
  transition: transform var(--transition-normal);
}

.modal-overlay.active .modal-dialog {
  transform: scale(1);
}

.modal-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-title {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-primary);
}

.modal-close-btn {
  background: transparent;
  border: none;
  cursor: pointer;
  color: var(--text-muted);
  font-size: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 4px;
}

.modal-close-btn:hover {
  background: var(--bg-subtle);
  color: var(--text-primary);
}

.modal-body {
  padding: 20px;
}

.modal-footer {
  padding: 12px 20px;
  border-top: 1px solid var(--border-color);
  background: var(--bg-subtle);
  display: flex;
  justify-content: flex-end;
  gap: 10px;
}

.btn-secondary {
  background: var(--bg-surface);
  border: 1px solid var(--border-color);
  color: var(--text-primary);
  padding: 6px 14px;
  border-radius: 6px;
  font-size: 13px;
  cursor: pointer;
}

.btn-primary {
  background: var(--primary-color);
  border: none;
  color: white;
  padding: 6px 16px;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
}