:root {
  --primary: #2563eb;
  --primary-hover: #1d4ed8;
  --danger: #dc2626;
  --danger-hover: #b91c1c;
  --bg: #ffffff;
  --bg-secondary: #f3f4f6;
  --border: #e5e7eb;
  --text: #111827;
  --text-secondary: #6b7280;
  --user-bg: #dbeafe;
  --assistant-bg: #f3f4f6;
  --shadow: rgba(0, 0, 0, 0.1);
}

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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  color: var(--text);
  background: var(--bg);
  overflow: hidden;
}

.app {
  height: 100vh;
  display: flex;
  flex-direction: column;
}

/* Header */
.header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem;
  background: var(--primary);
  color: white;
  box-shadow: 0 2px 8px var(--shadow);
  z-index: 10;
}

.header h1 {
  font-size: 1.5rem;
  font-weight: 600;
}

.header-actions {
  display: flex;
  gap: 0.5rem;
}

.icon-btn {
  background: rgba(255, 255, 255, 0.2);
  border: none;
  border-radius: 8px;
  padding: 0.5rem;
  cursor: pointer;
  color: white;
  transition: background 0.2s;
  display: flex;
  align-items: center;
  justify-content: center;
}

.icon-btn:hover {
  background: rgba(255, 255, 255, 0.3);
}

/* Main Content */
.main {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.chat-container {
  flex: 1;
  overflow-y: auto;
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.welcome-message {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--text-secondary);
}

.welcome-message h2 {
  color: var(--text);
  margin-bottom: 0.5rem;
}

/* Messages */
.message {
  display: flex;
  animation: slideIn 0.3s ease-out;
}

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

.message-user {
  justify-content: flex-end;
}

.message-content {
  max-width: 80%;
  padding: 0.75rem 1rem;
  border-radius: 12px;
  word-wrap: break-word;
  white-space: pre-wrap;
}

.message-user .message-content {
  background: var(--user-bg);
  color: var(--text);
  border-bottom-right-radius: 4px;
}

.message-assistant .message-content {
  background: var(--assistant-bg);
  color: var(--text);
  border-bottom-left-radius: 4px;
}

/* Input Area */
.input-area {
  border-top: 1px solid var(--border);
  background: var(--bg);
  padding: 1rem;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.mcp-indicator {
  background: var(--bg-secondary);
  padding: 0.5rem;
  border-radius: 6px;
  font-size: 0.875rem;
  color: var(--text-secondary);
}

.input-wrapper {
  display: flex;
  gap: 0.5rem;
  align-items: flex-end;
}

#message-input {
  flex: 1;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.75rem;
  font-family: inherit;
  font-size: 1rem;
  resize: none;
  min-height: 44px;
  max-height: 150px;
  outline: none;
  transition: border-color 0.2s;
}

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

.send-btn {
  background: var(--primary);
  border: none;
  border-radius: 50%;
  width: 44px;
  height: 44px;
  color: white;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.2s;
  flex-shrink: 0;
}

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

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

.model-selector {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.875rem;
}

.model-selector label {
  color: var(--text-secondary);
}

#model-select {
  flex: 1;
  padding: 0.5rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-family: inherit;
  font-size: 0.875rem;
  outline: none;
  cursor: pointer;
}

/* Modal */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  z-index: 1000;
  align-items: center;
  justify-content: center;
  padding: 1rem;
}

.modal-content {
  background: var(--bg);
  border-radius: 12px;
  width: 100%;
  max-width: 600px;
  max-height: 90vh;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.5rem;
  border-bottom: 1px solid var(--border);
}

.modal-header h2 {
  font-size: 1.25rem;
  font-weight: 600;
}

.close-btn {
  background: none;
  border: none;
  font-size: 2rem;
  color: var(--text-secondary);
  cursor: pointer;
  line-height: 1;
  padding: 0;
  width: 32px;
  height: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 4px;
  transition: background 0.2s;
}

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

.modal-body {
  padding: 1.5rem;
  overflow-y: auto;
  flex: 1;
}

/* Settings */
.settings-section {
  margin-bottom: 2rem;
}

.settings-section h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}

.settings-note {
  color: var(--text-secondary);
  font-size: 0.875rem;
  margin-bottom: 1.5rem;
  line-height: 1.5;
}

.form-group {
  margin-bottom: 1.5rem;
  position: relative;
}

.form-group label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
  color: var(--text);
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid var(--border);
  border-radius: 6px;
  font-family: inherit;
  font-size: 1rem;
  outline: none;
  transition: border-color 0.2s;
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--primary);
}

.form-group textarea {
  resize: vertical;
  min-height: 60px;
}

.toggle-visibility {
  position: absolute;
  right: 0.75rem;
  top: 2.5rem;
  background: none;
  border: none;
  color: var(--primary);
  cursor: pointer;
  font-size: 0.875rem;
  font-weight: 500;
  padding: 0.25rem 0.5rem;
}

.toggle-visibility:hover {
  text-decoration: underline;
}

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

.btn {
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 6px;
  font-family: inherit;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s;
}

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

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

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

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

/* MCP Management */
.mcp-section {
  margin-bottom: 2rem;
}

.mcp-section h3 {
  font-size: 1.125rem;
  font-weight: 600;
  margin-bottom: 1rem;
}

.mcp-list {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.empty-state {
  text-align: center;
  color: var(--text-secondary);
  padding: 2rem;
  font-style: italic;
}

.mcp-item {
  background: var(--bg-secondary);
  border-radius: 8px;
  padding: 1rem;
  display: flex;
  gap: 1rem;
  align-items: start;
}

.mcp-info {
  flex: 1;
  min-width: 0;
}

.mcp-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 0.5rem;
}

.mcp-header h4 {
  font-size: 1rem;
  font-weight: 600;
}

.mcp-endpoint {
  font-size: 0.875rem;
  color: var(--text-secondary);
  word-break: break-all;
  font-family: 'Monaco', 'Courier New', monospace;
  margin-bottom: 0.25rem;
}

.mcp-description {
  font-size: 0.875rem;
  color: var(--text-secondary);
  line-height: 1.4;
}

.mcp-api-key-indicator {
  font-size: 0.75rem;
  color: #059669;
  margin-top: 0.25rem;
  font-weight: 500;
}

.btn-delete {
  background: var(--danger);
  border: none;
  border-radius: 6px;
  padding: 0.5rem;
  color: white;
  cursor: pointer;
  transition: background 0.2s;
  flex-shrink: 0;
}

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

/* Toggle Switch */
.switch {
  position: relative;
  display: inline-block;
  width: 44px;
  height: 24px;
}

.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: var(--border);
  transition: 0.3s;
  border-radius: 24px;
}

.slider:before {
  position: absolute;
  content: "";
  height: 18px;
  width: 18px;
  left: 3px;
  bottom: 3px;
  background-color: white;
  transition: 0.3s;
  border-radius: 50%;
}

input:checked + .slider {
  background-color: var(--primary);
}

input:checked + .slider:before {
  transform: translateX(20px);
}

/* Responsive */
@media (max-width: 640px) {
  .header h1 {
    font-size: 1.25rem;
  }
  
  .message-content {
    max-width: 90%;
  }
  
  .modal-content {
    max-width: 100%;
    max-height: 100vh;
    border-radius: 0;
  }
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-secondary);
}

::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--text-secondary);
}