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

/* --- Light Mode (Default) --- */
:root {
  --bg-base: #f2f2f7;
  --glass-bg: rgba(255, 255, 255, 0.72);
  --glass-bg-heavy: rgba(255, 255, 255, 0.85);
  --glass-border: rgba(0, 0, 0, 0.08);
  --text-primary: #1c1c1e;
  --text-secondary: #3c3c43;
  --text-muted: #8e8e93;
  --accent: #007AFF;
  --accent-hover: #0062cc;
  --accent-light: rgba(0, 122, 255, 0.12);
  --error: #FF3B30;
  --error-bg: rgba(255, 59, 48, 0.1);
  --success: #34C759;
  --success-bg: rgba(52, 199, 89, 0.1);
  --glass-shadow: 0 2px 16px rgba(0, 0, 0, 0.08);
  --glass-shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.12);
  --orb-1: rgba(0, 122, 255, 0.15);
  --orb-2: rgba(88, 86, 214, 0.12);
}

/* --- Dark Mode --- */
[data-theme="dark"] {
  --bg-base: #000000;
  --glass-bg: rgba(44, 44, 46, 0.65);
  --glass-bg-heavy: rgba(44, 44, 46, 0.82);
  --glass-border: rgba(255, 255, 255, 0.12);
  --text-primary: #ffffff;
  --text-secondary: #ebebf5;
  --text-muted: #8e8e93;
  --accent: #0A84FF;
  --accent-hover: #409cff;
  --accent-light: rgba(10, 132, 255, 0.15);
  --error: #FF453A;
  --error-bg: rgba(255, 69, 58, 0.15);
  --success: #30D158;
  --success-bg: rgba(48, 209, 88, 0.15);
  --glass-shadow: 0 2px 16px rgba(0, 0, 0, 0.3);
  --glass-shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.4);
  --orb-1: rgba(10, 132, 255, 0.12);
  --orb-2: rgba(94, 92, 230, 0.10);
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
  background-color: var(--bg-base);
  color: var(--text-primary);
  height: 100vh;
  overflow: hidden;
  position: relative;
}

/* Gradient mesh background */
body::before {
  content: '';
  position: fixed;
  top: -20%;
  left: -10%;
  width: 60%;
  height: 60%;
  background: radial-gradient(circle, var(--orb-1) 0%, transparent 70%);
  animation: orb-float-1 20s ease-in-out infinite;
  pointer-events: none;
  z-index: 0;
}

body::after {
  content: '';
  position: fixed;
  bottom: -20%;
  right: -10%;
  width: 50%;
  height: 50%;
  background: radial-gradient(circle, var(--orb-2) 0%, transparent 70%);
  animation: orb-float-2 25s ease-in-out infinite;
  pointer-events: none;
  z-index: 0;
}

@keyframes orb-float-1 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(10%, 15%) scale(1.1); }
  66% { transform: translate(-5%, -10%) scale(0.95); }
}

@keyframes orb-float-2 {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33% { transform: translate(-15%, -10%) scale(1.05); }
  66% { transform: translate(10%, 5%) scale(1.1); }
}

.app {
  display: flex;
  height: 100vh;
  position: relative;
  z-index: 1;
}

/* Sidebar */
.sidebar {
  width: 260px;
  background: var(--glass-bg);
  backdrop-filter: blur(24px) saturate(180%);
  -webkit-backdrop-filter: blur(24px) saturate(180%);
  display: flex;
  flex-direction: column;
  padding: 10px;
  border-right: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
  transition: transform 0.3s ease;
}

.sidebar.hidden {
  transform: translateX(-100%);
  position: absolute;
}

.new-chat-btn {
  width: 100%;
  padding: 12px;
  background-color: transparent;
  border: 1px solid var(--glass-border);
  border-radius: 14px;
  color: var(--text-primary);
  cursor: pointer;
  font-size: 14px;
  margin-bottom: 10px;
  transition: background-color 0.2s;
}

.new-chat-btn:hover {
  background-color: var(--accent-light);
  color: var(--accent);
}

.conversations-list {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.conversation-item {
  padding: 12px;
  border-radius: 14px;
  cursor: pointer;
  font-size: 14px;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: background-color 0.2s;
  color: var(--text-secondary);
}

.conversation-item:hover {
  background-color: var(--accent-light);
}

.conversation-item.active {
  background-color: var(--accent-light);
  color: var(--accent);
}

.conversation-item .title {
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
}

.conversation-item .delete-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px 8px;
  border-radius: 8px;
}

.conversation-item:hover .delete-btn {
  display: block;
}

.conversation-item .delete-btn:hover {
  background-color: var(--error-bg);
  color: var(--error);
}

.settings-btn {
  width: 100%;
  padding: 12px;
  background-color: transparent;
  border: 1px solid var(--glass-border);
  border-radius: 14px;
  color: var(--text-primary);
  cursor: pointer;
  font-size: 14px;
  margin-top: 10px;
  transition: background-color 0.2s;
}

.settings-btn:hover {
  background-color: var(--accent-light);
  color: var(--accent);
}

/* Chat Area */
.chat-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.chat-header {
  padding: 16px 20px;
  border-bottom: 1px solid var(--glass-border);
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--glass-bg);
  backdrop-filter: blur(24px) saturate(180%);
  -webkit-backdrop-filter: blur(24px) saturate(180%);
}

.chat-header h1 {
  font-size: 16px;
  font-weight: 500;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  color: var(--text-primary);
}

.menu-toggle {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 20px;
  cursor: pointer;
  padding: 4px 8px;
}

/* Theme Toggle */
.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: 10px;
  border: 1px solid var(--glass-border);
  background: var(--glass-bg);
  backdrop-filter: blur(12px) saturate(150%);
  -webkit-backdrop-filter: blur(12px) saturate(150%);
  cursor: pointer;
  transition: all 0.2s;
  color: var(--text-muted);
  margin-left: auto;
  margin-right: 8px;
}

.theme-toggle:hover {
  background: var(--glass-bg-heavy);
  color: var(--accent);
}

.theme-toggle svg { width: 18px; height: 18px; }
.theme-toggle .icon-sun { display: none; }
.theme-toggle .icon-moon { display: block; }
[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
[data-theme="dark"] .theme-toggle .icon-moon { display: none; }

.messages {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.welcome-message {
  text-align: center;
  padding: 40px 20px;
  color: var(--text-secondary);
}

.welcome-message h2 {
  margin-bottom: 10px;
  color: var(--text-primary);
}

.message {
  max-width: 800px;
  margin: 0 auto;
  width: 100%;
  padding: 16px 20px;
  border-radius: 20px;
  line-height: 1.6;
}

.message.user {
  background: var(--glass-bg);
  backdrop-filter: blur(12px) saturate(150%);
  -webkit-backdrop-filter: blur(12px) saturate(150%);
  border: 1px solid var(--glass-border);
  margin-left: auto;
  max-width: 70%;
}

.message.assistant {
  background-color: transparent;
}

.message-role {
  font-size: 12px;
  font-weight: 600;
  margin-bottom: 8px;
  color: var(--text-muted);
  text-transform: uppercase;
}

.message-content {
  white-space: pre-wrap;
  word-wrap: break-word;
}

.message.streaming .message-content::after {
  content: '';
  display: inline-block;
  width: 2px;
  height: 1em;
  background-color: var(--accent);
  margin-left: 2px;
  vertical-align: text-bottom;
  animation: blink 0.7s infinite;
}

@keyframes blink {
  0%, 50% { opacity: 1; }
  51%, 100% { opacity: 0; }
}

.message-content code {
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--glass-border);
  padding: 2px 6px;
  border-radius: 6px;
  font-family: 'Menlo', 'Monaco', 'Courier New', monospace;
  font-size: 14px;
}

.message-content pre {
  background: var(--glass-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  border: 1px solid var(--glass-border);
  padding: 16px;
  border-radius: 16px;
  overflow-x: auto;
  margin: 10px 0;
}

.message-content pre code {
  background: none;
  border: none;
  padding: 0;
}

.typing-indicator {
  display: flex;
  gap: 4px;
  padding: 10px;
}

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

.typing-indicator span:nth-child(1) { animation-delay: 0s; }
.typing-indicator span:nth-child(2) { animation-delay: 0.2s; }
.typing-indicator span:nth-child(3) { animation-delay: 0.4s; }

@keyframes bounce {
  0%, 60%, 100% { transform: translateY(0); }
  30% { transform: translateY(-4px); }
}

/* Input Area */
.input-area {
  padding: 20px;
  display: flex;
  gap: 12px;
  max-width: 800px;
  margin: 0 auto;
  width: 100%;
}

#messageInput {
  flex: 1;
  padding: 14px 16px;
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  background: var(--glass-bg);
  backdrop-filter: blur(12px) saturate(150%);
  -webkit-backdrop-filter: blur(12px) saturate(150%);
  color: var(--text-primary);
  font-size: 15px;
  resize: none;
  font-family: inherit;
  max-height: 200px;
  overflow-y: auto;
}

#messageInput:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
}

#messageInput::placeholder {
  color: var(--text-muted);
}

.send-btn {
  padding: 14px 24px;
  background-color: var(--accent);
  border: none;
  border-radius: 16px;
  color: white;
  font-size: 15px;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.2s, transform 0.15s;
  box-shadow: 0 2px 8px rgba(0, 122, 255, 0.25);
}

.send-btn:hover {
  background-color: var(--accent-hover);
  transform: translateY(-1px);
}

.send-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
}

/* Modal */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.4);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  justify-content: center;
  align-items: center;
  z-index: 1000;
}

.modal.active {
  display: flex;
}

.modal-content {
  background: var(--glass-bg-heavy);
  backdrop-filter: blur(40px) saturate(200%);
  -webkit-backdrop-filter: blur(40px) saturate(200%);
  border: 1px solid var(--glass-border);
  border-radius: 24px;
  width: 90%;
  max-width: 500px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--glass-shadow-lg);
}

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

.modal-header h2 {
  font-size: 18px;
  color: var(--text-primary);
}

.close-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 24px;
  cursor: pointer;
}

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

.modal-body {
  padding: 20px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  margin-bottom: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--text-secondary);
}

.form-group input,
.form-group select {
  width: 100%;
  padding: 12px;
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  color: var(--text-primary);
  font-size: 14px;
}

.form-group input:focus,
.form-group select:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
}

.form-group small {
  display: block;
  margin-top: 6px;
  color: var(--text-muted);
  font-size: 12px;
}

.save-btn {
  width: 100%;
  padding: 12px;
  background-color: var(--accent);
  border: none;
  border-radius: 14px;
  color: white;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: background-color 0.2s;
  box-shadow: 0 2px 8px rgba(0, 122, 255, 0.25);
}

.save-btn:hover {
  background-color: var(--accent-hover);
}

/* MCP Servers */
.mcp-servers-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-bottom: 12px;
}

.mcp-server-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 12px;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  font-size: 13px;
}

.mcp-server-item .server-info {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

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

.mcp-server-item .server-url {
  font-size: 11px;
  color: var(--text-muted);
}

.mcp-server-item .remove-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  padding: 4px 8px;
  font-size: 16px;
  border-radius: 8px;
}

.mcp-server-item .remove-btn:hover {
  background-color: var(--error-bg);
  color: var(--error);
}

.mcp-server-add {
  display: flex;
  gap: 8px;
  margin-bottom: 8px;
}

.mcp-server-add input {
  flex: 1;
  padding: 8px 10px;
  border: 1px solid var(--glass-border);
  border-radius: 10px;
  background: var(--glass-bg);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  color: var(--text-primary);
  font-size: 13px;
}

.mcp-server-add input:focus {
  outline: none;
  border-color: var(--accent);
}

.add-btn {
  padding: 8px 16px;
  background-color: var(--accent);
  border: none;
  border-radius: 10px;
  color: white;
  font-size: 13px;
  cursor: pointer;
  transition: background-color 0.2s;
}

.add-btn:hover {
  background-color: var(--accent-hover);
}

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

/* MCP Validation */
.mcp-validation-status {
  margin: 8px 0;
  padding: 8px 12px;
  border-radius: 12px;
  font-size: 13px;
  display: none;
}

.mcp-validation-status.loading {
  display: block;
  background: var(--glass-bg);
  color: var(--text-muted);
}

.mcp-validation-status.success {
  display: block;
  background-color: var(--success-bg);
  color: var(--success);
}

.mcp-validation-status.error {
  display: block;
  background-color: var(--error-bg);
  color: var(--error);
}

/* MCP Server Tools */
.mcp-server-tools {
  margin-top: 8px;
  padding: 8px;
  background: var(--glass-bg);
  border: 1px solid var(--glass-border);
  border-radius: 10px;
}

.mcp-server-tools-header {
  font-size: 11px;
  color: var(--text-muted);
  margin-bottom: 6px;
  text-transform: uppercase;
}

.mcp-tool-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 4px 0;
  font-size: 12px;
}

.mcp-tool-item input[type="checkbox"] {
  width: 14px;
  height: 14px;
  accent-color: var(--accent);
}

.mcp-tool-item label {
  flex: 1;
  cursor: pointer;
}

.mcp-tool-item .tool-name {
  color: var(--text-primary);
}

.mcp-tool-item .tool-description {
  color: var(--text-muted);
  font-size: 11px;
  display: block;
  margin-top: 2px;
}

.error-message {
  background-color: var(--error-bg);
  border: 1px solid var(--error);
  color: var(--error);
  padding: 12px 16px;
  border-radius: 14px;
  margin-bottom: 10px;
}

/* User Info in Header */
.user-info {
  display: flex;
  align-items: center;
  gap: 12px;
}

#userName {
  font-size: 14px;
  color: var(--text-muted);
}

.logout-btn {
  padding: 8px 16px;
  background-color: transparent;
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  color: var(--text-primary);
  cursor: pointer;
  font-size: 13px;
  transition: background-color 0.2s;
}

.logout-btn:hover {
  background-color: var(--accent-light);
  color: var(--accent);
}

/* Login Overlay */
.login-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: var(--bg-base);
  justify-content: center;
  align-items: center;
  z-index: 2000;
}

.login-overlay.active {
  display: flex;
}

.login-content {
  text-align: center;
  padding: 40px;
  background: var(--glass-bg);
  backdrop-filter: blur(24px) saturate(180%);
  -webkit-backdrop-filter: blur(24px) saturate(180%);
  border: 1px solid var(--glass-border);
  border-radius: 24px;
  box-shadow: var(--glass-shadow-lg);
}

.login-content h2 {
  margin-bottom: 16px;
  color: var(--text-primary);
}

.login-content p {
  margin-bottom: 24px;
  color: var(--text-secondary);
}

.login-btn {
  display: inline-block;
  padding: 14px 32px;
  background-color: var(--accent);
  color: white;
  text-decoration: none;
  border-radius: 14px;
  font-size: 16px;
  font-weight: 500;
  transition: background-color 0.2s;
  box-shadow: 0 2px 8px rgba(0, 122, 255, 0.25);
}

.login-btn:hover {
  background-color: var(--accent-hover);
}

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

::-webkit-scrollbar-track {
  background: transparent;
}

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

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

/* Responsive */
@media (max-width: 768px) {
  .sidebar {
    position: fixed;
    left: 0;
    top: 0;
    height: 100%;
    z-index: 100;
    transform: translateX(-100%);
  }

  .sidebar.visible {
    transform: translateX(0);
  }

  .menu-toggle {
    display: block;
  }

  .message.user {
    max-width: 85%;
  }

  .user-info {
    gap: 8px;
  }

  #userName {
    display: none;
  }
}