:root {
  --bg-color: #f7fafc;
  --bg-gradient: linear-gradient(135deg, #f0f4f8 0%, #e2e8f0 100%);
  --surface-color: #ffffff;
  --primary-color: #3b82f6;
  --primary-hover: #2563eb;
  --primary-light: #eff6ff;
  --text-main: #1e293b;
  --text-muted: #64748b;
  --border-color: #e2e8f0;
  --success-color: #10b981;
  --danger-color: #ef4444;
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-full: 9999px;
  --transition-fast: 0.15s ease-in-out;
  --transition-normal: 0.3s ease-in-out;
}

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

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg-gradient);
  background-attachment: fixed;
  color: var(--text-main);
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  overflow: hidden;
}

.app-container {
  width: 100%;
  max-width: 900px;
  height: 95vh;
  margin: auto;
  background-color: var(--surface-color);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

/* Header */
.chat-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
  background-color: var(--surface-color);
  z-index: 10;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.logo-icon {
  width: 28px;
  height: 28px;
  border-radius: var(--radius-md);
  background: linear-gradient(135deg, var(--primary-color), #60a5fa);
  box-shadow: var(--shadow-sm);
}

.logo h1 {
  font-size: 1.25rem;
  font-weight: 600;
  color: var(--text-main);
  letter-spacing: -0.025em;
}

.status {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
  color: var(--text-muted);
  font-weight: 500;
}

.status-indicator {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: var(--text-muted);
  transition: background-color var(--transition-normal);
}

.status-indicator.active {
  background-color: var(--success-color);
  box-shadow: 0 0 0 2px rgba(16, 185, 129, 0.2);
}

/* Main Chat Area */
.chat-main {
  flex: 1;
  overflow-y: auto;
  padding: 1.5rem;
  background-color: var(--bg-color);
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  scroll-behavior: smooth;
}

.messages-container {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.message {
  display: flex;
  gap: 1rem;
  max-width: 85%;
  animation: fadeIn 0.4s ease-out forwards;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.user-message {
  align-self: flex-end;
  flex-direction: row-reverse;
}

.system-message {
  align-self: flex-start;
}

.avatar {
  min-width: 40px;
  height: 40px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 0.875rem;
  flex-shrink: 0;
}

.system-avatar {
  background-color: var(--primary-light);
  color: var(--primary-color);
  border: 1px solid rgba(59, 130, 246, 0.2);
}

.user-avatar {
  background: linear-gradient(135deg, var(--primary-color), #60a5fa);
  color: white;
  box-shadow: var(--shadow-sm);
}

.message-content {
  padding: 1rem;
  border-radius: var(--radius-lg);
  font-size: 0.95rem;
  line-height: 1.5;
  box-shadow: var(--shadow-sm);
}

.system-message .message-content {
  background-color: var(--surface-color);
  border: 1px solid var(--border-color);
  border-top-left-radius: 0;
  color: var(--text-main);
}

.user-message .message-content {
  background-color: var(--primary-color);
  color: white;
  border-top-right-radius: 0;
}

.message-content p {
  margin-bottom: 0.5rem;
}

.message-content p:last-child {
  margin-bottom: 0;
}

.message-content pre {
  background-color: #1e293b;
  color: #f8fafc;
  padding: 1rem;
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin: 0.75rem 0;
  font-size: 0.875rem;
  font-family: monospace;
}

.message-content code {
  background-color: rgba(0, 0, 0, 0.05);
  padding: 0.1rem 0.3rem;
  border-radius: 0.25rem;
  font-family: monospace;
  font-size: 0.875rem;
}

.user-message .message-content code {
  background-color: rgba(255, 255, 255, 0.2);
}

/* Typing Indicator */
.typing-indicator {
  display: flex;
  gap: 0.3rem;
  padding: 0.5rem 1rem;
  background-color: var(--surface-color);
  border-radius: var(--radius-full);
  align-self: flex-start;
  width: fit-content;
  box-shadow: var(--shadow-sm);
  border: 1px solid var(--border-color);
  margin-left: 3.5rem;
}

.typing-indicator span {
  width: 8px;
  height: 8px;
  background-color: var(--primary-color);
  border-radius: 50%;
  animation: typingBounce 1.4s infinite ease-in-out both;
}

.typing-indicator span:nth-child(1) { animation-delay: -0.32s; }
.typing-indicator span:nth-child(2) { animation-delay: -0.16s; }

@keyframes typingBounce {
  0%, 80%, 100% { transform: scale(0); opacity: 0.5; }
  40% { transform: scale(1); opacity: 1; }
}

.hidden {
  display: none !important;
}

/* Footer & Input Area */
.chat-footer {
  background-color: var(--surface-color);
  border-top: 1px solid var(--border-color);
  padding: 1rem 1.5rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
  z-index: 10;
}

.input-area {
  display: flex;
  gap: 1rem;
  align-items: flex-end;
}

.input-area textarea {
  flex: 1;
  padding: 0.875rem 1rem;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  font-family: inherit;
  font-size: 0.95rem;
  resize: none;
  background-color: var(--bg-color);
  color: var(--text-main);
  transition: border-color var(--transition-fast), box-shadow var(--transition-fast);
  max-height: 150px;
  overflow-y: auto;
}

.input-area textarea:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
  background-color: var(--surface-color);
}

.btn-send {
  background-color: var(--primary-color);
  color: white;
  border: none;
  border-radius: var(--radius-md);
  width: 48px;
  height: 48px;
  display: flex;
  justify-content: center;
  align-items: center;
  cursor: pointer;
  transition: background-color var(--transition-fast), transform 0.1s ease;
  flex-shrink: 0;
}

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

.btn-send:active {
  transform: scale(0.95);
}

.btn-send:disabled {
  background-color: var(--text-muted);
  cursor: not-allowed;
  transform: none;
}

/* Approval Panel */
.approval-panel {
  background: linear-gradient(to right, #eff6ff, #f0fdf4);
  border: 1px solid #bfdbfe;
  padding: 1rem;
  border-radius: var(--radius-md);
  animation: slideUp 0.3s ease-out;
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}

.approval-panel p {
  color: #1e40af;
  margin-bottom: 0.75rem;
  font-size: 0.9rem;
}

.approval-actions {
  display: flex;
  gap: 0.75rem;
}

.btn {
  padding: 0.5rem 1rem;
  border-radius: var(--radius-md);
  font-weight: 500;
  font-size: 0.875rem;
  cursor: pointer;
  border: none;
  transition: all var(--transition-fast);
}

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

.btn-success:hover {
  background-color: #059669;
}

.btn-danger {
  background-color: white;
  color: var(--danger-color);
  border: 1px solid #fca5a5;
}

.btn-danger:hover {
  background-color: #fef2f2;
  border-color: var(--danger-color);
}

/* Markdown specific styles in messages */
.message-content h1, .message-content h2, .message-content h3 {
  margin: 1rem 0 0.5rem 0;
  font-weight: 600;
}

.message-content ul, .message-content ol {
  margin-left: 1.5rem;
  margin-bottom: 0.5rem;
}

.message-content li {
  margin-bottom: 0.25rem;
}

.message-event-type {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 0.25rem;
  font-weight: 600;
}

/* Modal Overlay */
.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background-color: rgba(15, 23, 42, 0.6);
  backdrop-filter: blur(4px);
  display: flex;
  justify-content: center;
  align-items: center;
  z-index: 100;
  animation: fadeIn 0.3s ease-out;
}

.modal-content {
  background-color: var(--surface-color);
  width: 90%;
  max-width: 500px;
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: var(--shadow-lg);
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.modal-header {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.5rem;
}

.modal-header h2 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-main);
}

.modal-subtitle {
  color: var(--text-muted);
  font-size: 0.95rem;
  margin-top: -1rem;
}

.form-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.form-group label {
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-main);
}

.form-group input {
  padding: 0.75rem 1rem;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  font-family: inherit;
  font-size: 1rem;
  transition: all var(--transition-fast);
}

.form-group input:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.project-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  max-height: 200px;
  overflow-y: auto;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 0.5rem;
  background-color: var(--bg-color);
}

.project-item {
  padding: 0.75rem;
  border-radius: var(--radius-md);
  cursor: pointer;
  border: 1px solid transparent;
  transition: all var(--transition-fast);
  background-color: var(--surface-color);
}

.project-item:hover {
  background-color: var(--primary-light);
  border-color: #bfdbfe;
}

.project-item.selected {
  background-color: var(--primary-light);
  border-color: var(--primary-color);
  box-shadow: 0 0 0 1px var(--primary-color);
}

.project-item-title {
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text-main);
}

.project-item-sub {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 0.2rem;
}

.loading-text {
  padding: 1rem;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.875rem;
}

.btn-primary {
  background-color: var(--primary-color);
  color: white;
  width: 100%;
  padding: 0.875rem;
  font-size: 1rem;
}

.btn-primary:hover:not(:disabled) {
  background-color: var(--primary-hover);
}

.btn-primary:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.btn-secondary {
  background-color: transparent;
  color: var(--text-main);
  border: 1px solid var(--border-color);
  width: 100%;
  padding: 0.875rem;
  font-size: 1rem;
}

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

.divider {
  display: flex;
  align-items: center;
  text-align: center;
  color: var(--text-muted);
  font-size: 0.875rem;
}

.divider::before,
.divider::after {
  content: '';
  flex: 1;
  border-bottom: 1px solid var(--border-color);
}

.divider::not(:empty)::before {
  margin-right: .5em;
}

.divider::not(:empty)::after {
  margin-left: .5em;
}