:root {
  --primary-color: #f97316;
  --primary-hover: #ea580c;
  --secondary-color: #3b82f6;
  --secondary-hover: #2563eb;
  --success-color: #10b981;
  --success-hover: #059669;
  --danger-color: #dc2626;
  --danger-hover: #b91c1c;

  --text-primary: #1a1a1a;
  --text-secondary: #666;
  --text-tertiary: #999;

  --bg-primary: #f5f5f5;
  --bg-secondary: white;
  --bg-tertiary: #f9f9f9;
  --bg-hover: #f0f0f0;

  --border-color: #e0e0e0;
  --border-light: #f0f0f0;
  --border-input: #d0d0d0;

  --shadow-sm: 0 2px 4px rgba(0,0,0,0.1);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.15);

  --radius-sm: 3px;
  --radius-md: 6px;
  --radius-lg: 8px;
  --radius-xl: 12px;

  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 12px;
  --spacing-lg: 16px;
  --spacing-xl: 20px;
  --spacing-2xl: 24px;

  --sidebar-width: 360px;
  --sidebar-min: 330px;
  --sidebar-max: 600px;

  --font-xs: 11px;
  --font-sm: 12px;
  --font-md: 14px;
  --font-ml: 17px;
  --font-lg: 18px;
  --font-xl: 20px;
  --font-2xl: 24px;
  --transition: all 0.2s ease;
}

/* Smooth transitions for dark mode */
body {
  transition: background-color 0.3s ease, color 0.3s ease;
}

.sidebar, .main-content, .chat-item, .message, .modal-content, .search-input, .date-input {
  transition: background-color 0.3s ease, border-color 0.3s ease, color 0.3s ease;
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: var(--bg-primary);
  height: 100vh;
  overflow: hidden;
}

/* Layout */
#app {
  display: flex;
  height: 100vh;
}

.sidebar {
  width: var(--sidebar-width);
  min-width: var(--sidebar-min);
  max-width: var(--sidebar-max);
  flex-shrink: 0; /* Prevent flexbox from overriding width */
  background: var(--bg-secondary);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  position: relative;
  overflow-y: auto; /* Ensure scrolling works if content exceeds height */
}

.main-content {
  flex: 1;
  display: flex;
  flex-direction: column;
  background: var(--bg-secondary);
  /* margin: 0px 10px; */
  position: relative; /* Positioning context for loading modal */
  overflow: auto;
}
.chat-view {
  display: contents;
}

/* Buttons */
.btn {
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--font-md);
  font-weight: 500;
  padding: var(--spacing-sm) var(--spacing-lg);
  transition: var(--transition);
}

.btn-primary {
  background: var(--primary-color);
  color: white;
}

.btn-primary:hover {
  background: var(--primary-hover);
}

.btn-secondary {
  background: var(--secondary-color);
  color: white;
}

.btn-secondary:hover {
  background: var(--secondary-hover);
}

.btn-success {
  background: var(--success-color);
  color: white;
}

.btn-success:hover {
  background: var(--success-hover);
}

.btn-danger {
  background: var(--danger-color);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--font-md);
  font-weight: 700;
  padding: var(--spacing-sm) var(--spacing-lg);
  transition: var(--transition);
  color: white;
  flex: 1;
}

.btn-danger:hover {
  background: var(--danger-hover);
}

.btn-ghost {
  background: var(--bg-tertiary);
  color: var(--text-secondary);
}

.btn-ghost:hover {
  background: var(--bg-hover);
}

.btn-icon {
  background: none;
  border: none;
  color: var(--text-tertiary);
  cursor: pointer;
  padding: var(--spacing-xs);
  border-radius: var(--radius-sm);
  font-size: var(--font-sm);
  transition: var(--transition);
}

.btn-icon:hover {
  background: var(--bg-hover);
  color: var(--text-secondary);
}

/* Inputs */
.input {
  padding: var(--spacing-sm) var(--spacing-md);
  border: 1px solid var(--border-input);
  border-radius: var(--radius-md);
  font-size: var(--font-md);
  outline: none;
  transition: var(--transition);
}

.input:focus {
  border-color: var(--primary-color);
}

/* Sidebar Header */
.sidebar-header {
  padding: var(--spacing-xl);
  padding-top: max(var(--spacing-xl), env(safe-area-inset-top)); /* Account for notch/status bar */
  border-bottom: 1px solid var(--border-color);
}

.sidebar-header h1 {
  font-size: var(--font-xl);
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: var(--spacing-sm);
  text-align: center;
}

.header-buttons {
  display: flex;
  gap: var(--spacing-sm);
}

.header-buttons .btn {
  flex: 1;
}

.import-button {
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--font-md);
  font-weight: 500;
  padding: var(--spacing-sm) var(--spacing-lg);
  transition: var(--transition);
  background: var(--primary-color);
  color: white;
  flex: 1;
}

.import-button:hover {
  background: var(--primary-hover);
}

.dark-mode-toggle {
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: 16px;
  padding: 8px 10px;
  background: rgb(240 240 240 / 30%);
  color: #f4f4f5;
  border: 1px solid #d6c9c9;
  transition: all 0.2s ease;
  flex: 0 0 auto;
  margin-right: var(--spacing-sm);
}

.dark-mode-toggle:hover {
  background: #3a3a3b; /* Darker hover for light mode */
  transform: scale(1.05);
}

.manage-tags-button {
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-size: var(--font-md);
  font-weight: 500;
  padding: var(--spacing-sm) var(--spacing-lg);
  transition: var(--transition);
  background: var(--secondary-color);
  color: white;
  flex: 1;
}

.manage-tags-button:hover {
  background: var(--secondary-hover);
}

/* Assistant Filter */
.assistant-filter {
  display: flex;
  gap: var(--spacing-xs);
  padding: var(--spacing-lg) var(--spacing-xl) 0;
  margin-bottom: var(--spacing-lg);
}

.assistant-filter-btn {
  flex: 1;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 1px solid #d1d5db;
  border-radius: var(--radius-md);
  background: var(--bg-secondary);
  color: #6b7280;
  font-size: var(--font-sm);
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  position: relative;
}

.assistant-filter-btn:hover {
  background: #f3f4f6;
  border-color: #9ca3af;
}

.assistant-filter-btn.active {
  background: var(--secondary-color);
  border-color: var(--secondary-color);
  color: white;
}

.assistant-filter-btn[data-assistant="claude"].active {
  background: var(--primary-color);
  border-color: var(--primary-color);
}

.assistant-filter-btn[data-assistant="gpt"].active {
  background: var(--success-color);
  border-color: var(--success-color);
}

/* Count badges for assistant filter buttons */
.count-badge {
  position: absolute;
  top: -8px;
  right: -3px;
  background: #ef4444;
  color: white;
  font-size: 10px;
  font-weight: 600;
  padding: 2px 6px;
  border-radius: 10px;
  line-height: 1;
  min-width: 16px;
  text-align: center;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.2);
}

/* Search */
.search-container {
  padding: 26px var(--spacing-xl);
  border-bottom: 1px solid var(--border-color);
}

.search-input-wrapper {
  position: relative;
}

.search-input {
  width: 100%;
  padding: var(--spacing-sm) 30px var(--spacing-sm) var(--spacing-md);
}

.clear-search-btn {
  position: absolute;
  right: var(--spacing-md);
  top: 50%;
  transform: translateY(-50%);
  display: none;
}

.date-search {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-sm);
}

.date-input {
  flex: 1;
  padding: var(--spacing-md) var(--spacing-sm);
  font-size: var(--font-sm);
}

/* Tag Filters */
.tag-filter-section {
  padding: 0 var(--spacing-xl) var(--spacing-lg);
  border-bottom: 1px solid var(--border-color);
}

.tag-filter-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-md);
}

.tag-filter-header h4 {
  font-size: var(--font-sm);
  font-weight: 600;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.clear-filters-btn {
  background: none;
  border: none;
  color: var(--danger-color);
  cursor: pointer;
  font-size: var(--font-xs);
  font-weight: 500;
  padding: 2px var(--spacing-md);
  border-radius: var(--radius-sm);
  transition: var(--transition);
}

.clear-filters-btn:hover {
  background: #fee2e2;
}

.tag-filters {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-md);
}

.tag-filter {
  background: transparent;
  border: 1px solid;
  border-radius: var(--radius-xl);
  padding: var(--spacing-xs) 10px;
  font-size: var(--font-xs);
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
  font-family: inherit;
}

.tag-filter:hover {
  transform: translateY(-1px);
  box-shadow: var(--shadow-sm);
}

.tag-filter.active {
  transform: none;
  box-shadow: inset 0 1px 2px rgba(0,0,0,0.1);
}

/* Modal */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 1000;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.modal.show {
  opacity: 1;
}

.modal-content {
  background: var(--bg-secondary);
  padding: var(--spacing-2xl);
  border-radius: var(--radius-lg);
  max-width: 400px;
  width: 90%;
  box-shadow: var(--shadow-md);
  transform: scale(0.9);
  transition: transform 0.3s ease;
}

.modal.show .modal-content {
  transform: scale(1);
}

.modal-content h3 {
  margin: 0 0 var(--spacing-md) 0;
  color: var(--text-primary);
  font-size: var(--font-lg);
}

.modal-content p {
  margin: 0 0 var(--spacing-xl) 0;
  color: var(--text-secondary);
  line-height: 1.5;
}

.modal-buttons {
  display: flex;
  gap: var(--spacing-md);
  justify-content: flex-end;

  #cancel-delete, #confirm-delete {
    padding: 6px 6px;
    border-radius: 4px;
    border: 1px solid #ccc;
  }
  #cancel-delete:hover, #confirm-delete:hover {
    padding: 6px 6px;
    border-radius: 4px;
    border: 1px solid #aaa;
    background-color: #aaa;
    color: #fff
  }
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--spacing-xl);
}

.close-btn {
  background: none;
  border: none;
  font-size: var(--font-2xl);
  color: var(--text-secondary);
  cursor: pointer;
  padding: 0;
  width: 30px;
  height: 30px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.close-btn:hover {
  color: var(--text-primary);
}

/* Tag Management */
.tag-create-section {
  margin-bottom: var(--spacing-2xl);
  padding-bottom: var(--spacing-xl);
  border-bottom: 1px solid var(--border-color);
}

.input-group {
  display: flex;
  gap: var(--spacing-md);
  align-items: center;
}

#new-tag-input {
  flex: 1;
  padding: 10px var(--spacing-md);
  border: 1px solid #d1d5db;
  border-radius: var(--radius-md);
  font-size: var(--font-md);
  outline: none;
}

#new-tag-input:focus {
  border-color: var(--secondary-color);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.create-btn {
  padding: 10px var(--spacing-lg);
}

.create-btn:disabled {
  background: #d1d5db;
  cursor: not-allowed;
}

/* Color Selector */
.color-selector {
  margin-top: var(--spacing-md);
}

.color-selector label {
  display: block;
  margin-bottom: var(--spacing-sm);
  font-size: var(--font-sm);
  font-weight: 500;
  color: var(--text-secondary);
}

.color-options {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

.color-option {
  width: 21px;
  height: 21px;
  border: 2px solid transparent;
  border-radius: 50%;
  cursor: pointer;
  transition: all 0.2s ease;
  position: relative;
}

.color-option:hover {
  transform: scale(1.1);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.color-option.selected {
  border-color: var(--text-primary);
  box-shadow: 0 0 0 2px var(--bg-secondary), 0 0 0 4px var(--text-primary);
}

.color-option.selected::after {
  content: '✓';
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: white;
  font-size: 14px;
  font-weight: bold;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.5);
}

/* Tag List Styling */
.tag-actions {
  display: flex;
  gap: var(--spacing-sm);
}

.tag-edit-btn, .tag-save-btn, .tag-cancel-btn {
  padding: 4px 8px;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s ease;
  background: none;
  border: none;
  font-size: var(--font-ml);
}

.tag-edit-btn:hover, .tag-save-btn:hover {
  background: var(--secondary-color);
  color: white;
  border-color: var(--secondary-color);
}

.tag-cancel-btn:hover {
  background: var(--text-secondary);
  color: white;
  border-color: var(--text-secondary);
}

.tag-edit-input {
  width: 100%;
  padding: 8px 12px;
  border: 1px solid var(--secondary-color);
  border-radius: var(--radius-sm);
  font-size: var(--font-sm);
  background: var(--bg-secondary);
  color: var(--text-primary);
  font-weight: 500;
}

.tag-edit-input:focus {
  outline: none;
  box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.2);
}

.tag-edit-layout {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  width: 100%;
}

.tag-edit-colors {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  justify-content: flex-start;
  padding: var(--spacing-xs);
  background: var(--bg-tertiary);
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
}

.tag-edit-colors .color-option {
  width: 24px;
  height: 24px;
  border: 2px solid transparent;
  border-radius: 50%;
  cursor: pointer;
  transition: all 0.2s ease;
  flex-shrink: 0;
}

.tag-edit-colors .color-option:hover {
  transform: scale(1.2);
}

.tag-edit-colors .color-option.selected {
  border-color: var(--text-primary);
  box-shadow: 0 0 0 1px var(--bg-secondary), 0 0 0 2px var(--text-primary);
}

.tags-list {
  max-height: 300px;
  overflow-y: auto;
}

.tag-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-lg);
  margin-bottom: var(--spacing-sm);
  background: var(--bg-secondary);
}

.tag-info {
  display: flex;
  align-items: center;
  gap: var(--spacing-md);
}

.tag-color-dot {
  width: var(--spacing-md);
  height: var(--spacing-md);
  border-radius: 50%;
  border: 1px solid rgba(0,0,0,0.1);
}

.tag-name {
  font-weight: 500;
  color: var(--text-primary);
}

.tag-count {
  font-size: var(--font-sm);
  color: #000;
  background: #f3f4f6;
  padding: 2px var(--spacing-md);
  border-radius: 10px;
}

.tag-delete-btn {
  background: none;
  border: none;
  color: var(--danger-color);
  cursor: pointer;
  padding: var(--spacing-xs) var(--spacing-sm);
  border-radius: var(--spacing-xs);
  font-size: var(--font-ml);
  transition: var(--transition);
}

.tag-delete-btn:hover {
  background: #fee2e2;
}

.conversation-title {
  margin-bottom: var(--spacing-lg);
  padding: var(--spacing-md);
  background: #f8f9fa;
  border-radius: var(--radius-md);
}

.current-tags {
  margin-bottom: var(--spacing-xl);
}

.no-tags {
  color: var(--text-tertiary);
  font-style: italic;
  text-align: center;
  padding: var(--spacing-md);
}

.available-tags h4 {
  margin-bottom: var(--spacing-md);
  color: var(--text-primary);
  font-size: var(--font-md);
  font-weight: 600;
}

.tags-grid {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

/* Resize Handle */
.resize-handle {
  position: absolute;
  top: 0;
  right: -10px; /* Extend into main content for easier grabbing */
  width: 20px; /* Wider for better touch/mouse targeting */
  height: 100%;
  cursor: ew-resize;
  background: transparent;
  z-index: 10;
}

.resize-handle:hover {
  background: rgba(59, 130, 246, 0.3);
}

.resize-handle:active {
  background: rgba(59, 130, 246, 0.5);
}

.resize-handle::before {
  content: '';
  position: absolute;
  top: 50%;
  left: 1px;
  transform: translateY(-50%);
  width: 2px;
  height: 40px;
  background: var(--border-color);
  border-radius: 1px;
  opacity: 0;
  transition: var(--transition);
}

.resize-handle:hover::before {
  opacity: 1;
}

/* Scrollbars */
.chat-list::-webkit-scrollbar,
.chat-messages::-webkit-scrollbar {
  width: 6px;
}

.chat-list::-webkit-scrollbar-track,
.chat-messages::-webkit-scrollbar-track {
  background: transparent;
}

.chat-list::-webkit-scrollbar-thumb,
.chat-messages::-webkit-scrollbar-thumb {
  background: #ccc;
  border-radius: var(--radius-sm);
}

.chat-list::-webkit-scrollbar-thumb:hover,
.chat-messages::-webkit-scrollbar-thumb:hover {
  background: var(--text-tertiary);
}

/* Loading Modal */
.loading-modal {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10000;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease;
}

.loading-modal.visible {
  opacity: 1;
  visibility: visible;
}

.loading-content {
  background: var(--bg-primary);
  padding: var(--spacing-2xl);
  border-radius: var(--radius-lg);
  text-align: center;
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  min-width: 200px;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid var(--bg-secondary);
  border-top: 4px solid var(--primary-color);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin: 0 auto var(--spacing-md);
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.loading-text {
  color: var(--text-primary);
  font-size: var(--font-md);
  font-weight: 500;
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  top: 20px;
  right: 20px;
  z-index: 10001;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
  pointer-events: none;
}

.toast {
  background: var(--bg-primary);
  color: var(--text-primary);
  padding: var(--spacing-md) var(--spacing-lg);
  border-radius: var(--radius-lg);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
  border-left: 4px solid var(--primary-color);
  min-width: 300px;
  max-width: 400px;
  opacity: 0;
  transform: translateX(100%);
  transition: all 0.3s ease;
  pointer-events: auto;
  position: relative;
}

.toast.visible {
  opacity: 1;
  transform: translateX(0);
}

.toast.error {
  border-left-color: #ef4444;
  background: #fef2f2;
  color: #dc2626;
}

.toast.success {
  border-left-color: #10b981;
  background: #f0fdf4;
  color: #059669;
}

.toast.warning {
  border-left-color: #f59e0b;
  background: #fffbeb;
  color: #d97706;
}

.toast-message {
  font-size: var(--font-sm);
  line-height: 1.4;
  margin: 0;
}

.toast-close {
  position: absolute;
  top: 8px;
  right: 8px;
  background: none;
  border: none;
  color: inherit;
  opacity: 0.6;
  cursor: pointer;
  font-size: 16px;
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  transition: opacity 0.2s ease;
}

.toast-close:hover {
  opacity: 1;
  background: rgba(0, 0, 0, 0.1);
}

/* Confirmation Modal */
.confirm-modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 10002;
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.2s ease, visibility 0.2s ease;
}

.confirm-modal.visible {
  opacity: 1;
  visibility: visible;
}

.confirm-content {
  background: var(--bg-primary);
  padding: var(--spacing-2xl);
  border-radius: var(--radius-lg);
  box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
  min-width: 400px;
  max-width: 500px;
  text-align: center;
}

.confirm-message {
  color: var(--text-primary);
  font-size: var(--font-md);
  margin-bottom: var(--spacing-2xl);
  line-height: 1.5;
}

.confirm-buttons {
  display: flex;
  gap: var(--spacing-md);
  justify-content: center;
}

.confirm-btn {
  padding: var(--spacing-sm) var(--spacing-2xl);
  border: none;
  border-radius: var(--radius-md);
  font-size: var(--font-sm);
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
}

.confirm-btn.primary {
  background: #ef4444;
  color: white;
}

.confirm-btn.primary:hover {
  background: #dc2626;
}

.confirm-btn.secondary {
  background: var(--bg-secondary);
  color: var(--text-primary);
  border: 1px solid #d1d5db;
}

.confirm-btn.secondary:hover {
  background: #f3f4f6;
}