/* Reset & Base */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  /* ChatGPT-inspired colors */
  --bg-primary: #212121;
  --bg-secondary: #171717;
  --bg-tertiary: #2f2f2f;
  --bg-hover: #3a3a3a;
  --bg-active: #424242;
  
  --text-primary: #ececec;
  --text-secondary: #b4b4b4;
  --text-tertiary: #8e8e8e;
  
  --border-color: #3a3a3a;
  --accent: #10a37f;
  --accent-hover: #0d8a6c;
  
  --message-user-bg: #2f2f2f;
  --message-assistant-bg: transparent;
  
  --sidebar-width: 260px;
  --header-height: 56px;
  
  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  
  --radius-sm: 6px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 24px;
}

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.5;
  overflow: hidden;
}

/* App Layout */
.app {
  display: flex;
  height: 100vh;
  width: 100vw;
}

/* Sidebar */
.sidebar {
  width: var(--sidebar-width);
  background: var(--bg-secondary);
  display: flex;
  flex-direction: column;
  border-right: 1px solid var(--border-color);
  transition: transform 0.3s ease;
}

.sidebar-header {
  padding: 12px;
}

.new-chat-btn {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 14px;
  background: transparent;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s ease, border-color 0.15s ease;
}

.new-chat-btn:hover {
  background: var(--bg-tertiary);
  border-color: var(--text-tertiary);
}

.sidebar-section {
  flex: 1;
  overflow-y: auto;
  padding: 0 12px;
}

.sidebar-label {
  display: block;
  padding: 12px 8px 8px;
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-tertiary);
}

.pinned-chats {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.chat-item {
  display: flex;
  align-items: center;
  gap: 10px;
  width: 100%;
  padding: 10px 12px;
  background: transparent;
  border: none;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  font-size: 14px;
  text-align: left;
  cursor: pointer;
  transition: background 0.15s ease, color 0.15s ease;
}

.chat-item:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

.chat-item.active {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

.chat-item svg {
  flex-shrink: 0;
  opacity: 0.7;
}

.chat-item span {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.sidebar-footer {
  padding: 12px;
  border-top: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
  gap: 12px;
}

/* AI Stats Badge */
.ai-stats {
  background: linear-gradient(135deg, rgba(16, 163, 127, 0.08) 0%, rgba(16, 163, 127, 0.03) 100%);
  border: 1px solid rgba(16, 163, 127, 0.2);
  border-radius: var(--radius-md);
  padding: 10px 12px;
  cursor: default;
  transition: border-color 0.2s ease, background 0.2s ease;
}

.ai-stats:hover {
  border-color: rgba(16, 163, 127, 0.4);
  background: linear-gradient(135deg, rgba(16, 163, 127, 0.12) 0%, rgba(16, 163, 127, 0.05) 100%);
}

.ai-stats-header {
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 8px;
}

.ai-icon {
  font-size: 12px;
  animation: pulse 2s infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.ai-total {
  font-size: 13px;
  font-weight: 600;
  color: var(--accent);
  letter-spacing: -0.01em;
}

.ai-year {
  font-size: 10px;
  color: var(--text-tertiary);
  margin-left: auto;
  padding: 2px 6px;
  background: var(--bg-tertiary);
  border-radius: 4px;
}

.ai-models {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.ai-model {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 11px;
}

.model-name {
  color: var(--text-tertiary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
  max-width: 140px;
}

.model-count {
  color: var(--text-secondary);
  font-variant-numeric: tabular-nums;
  font-weight: 500;
}

.social-links {
  display: flex;
  gap: 8px;
  justify-content: center;
}

.social-links a {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  transition: background 0.15s ease, color 0.15s ease;
}

.social-links a:hover {
  background: var(--bg-tertiary);
  color: var(--text-primary);
}

.book-call-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 16px;
  background: var(--accent);
  border: none;
  border-radius: var(--radius-sm);
  color: white;
  font-size: 14px;
  font-weight: 500;
  text-decoration: none;
  cursor: pointer;
  transition: background 0.15s ease;
}

.book-call-btn:hover {
  background: var(--accent-hover);
}

/* Main Chat Area */
.chat-main {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
  background: var(--bg-primary);
}

.chat-header {
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 16px;
  border-bottom: 1px solid var(--border-color);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  cursor: pointer;
  padding: 8px;
  margin: -8px;
}

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

.header-spacer {
  width: 40px;
}

/* Chat Messages */
.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 24px 0;
}

.message {
  padding: 16px 24px;
  max-width: 768px;
  margin: 0 auto;
  animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(8px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.message-wrapper {
  display: flex;
  gap: 16px;
  align-items: flex-start;
}

.message-avatar {
  width: 32px;
  height: 32px;
  border-radius: var(--radius-sm);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-size: 14px;
  font-weight: 600;
}

.message.user .message-avatar {
  background: linear-gradient(135deg, #5436da 0%, #7c3aed 100%);
  color: white;
}

.message.assistant .message-avatar {
  background: var(--accent);
  color: white;
}

.message-content {
  flex: 1;
  min-width: 0;
}

.message-author {
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 4px;
  color: var(--text-primary);
}

.message-text {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-primary);
}

.message-text p {
  margin-bottom: 12px;
}

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

.message-text strong {
  font-weight: 600;
}

.message-text a {
  color: var(--accent);
  text-decoration: none;
}

.message-text a:hover {
  text-decoration: underline;
}

.message-text ul, .message-text ol {
  margin: 12px 0;
  padding-left: 24px;
}

.message-text li {
  margin-bottom: 6px;
}

.message-text code {
  background: var(--bg-tertiary);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: 'SF Mono', Monaco, monospace;
  font-size: 13px;
}

/* Quick Actions (suggestion chips) */
.quick-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 16px;
}

.quick-action {
  padding: 8px 14px;
  background: transparent;
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  color: var(--text-secondary);
  font-size: 13px;
  cursor: pointer;
  transition: all 0.15s ease;
}

.quick-action:hover {
  background: var(--bg-tertiary);
  border-color: var(--text-tertiary);
  color: var(--text-primary);
}

/* Welcome Screen */
.welcome-screen {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 24px;
  text-align: center;
  max-width: 600px;
  margin: 0 auto;
}

.welcome-avatar {
  width: 80px;
  height: 80px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--accent) 0%, #0d8a6c 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 24px;
  font-size: 32px;
}

.welcome-title {
  font-size: 28px;
  font-weight: 600;
  margin-bottom: 12px;
  color: var(--text-primary);
}

.welcome-subtitle {
  font-size: 16px;
  color: var(--text-secondary);
  margin-bottom: 32px;
  max-width: 400px;
}

.welcome-suggestions {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 12px;
  width: 100%;
  max-width: 500px;
}

.suggestion-card {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-md);
  padding: 16px;
  text-align: left;
  cursor: pointer;
  transition: all 0.15s ease;
}

.suggestion-card:hover {
  background: var(--bg-tertiary);
  border-color: var(--text-tertiary);
}

.suggestion-card h3 {
  font-size: 14px;
  font-weight: 500;
  color: var(--text-primary);
  margin-bottom: 4px;
}

.suggestion-card p {
  font-size: 13px;
  color: var(--text-tertiary);
}

/* Chat Input */
.chat-input-container {
  padding: 16px 24px 24px;
  max-width: 768px;
  margin: 0 auto;
  width: 100%;
}

.chat-input-wrapper {
  display: flex;
  align-items: flex-end;
  gap: 8px;
  background: var(--bg-tertiary);
  border: 1px solid var(--border-color);
  border-radius: var(--radius-xl);
  padding: 8px 8px 8px 16px;
  transition: border-color 0.15s ease;
}

.chat-input-wrapper:focus-within {
  border-color: var(--text-tertiary);
}

.chat-input-wrapper textarea {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 15px;
  line-height: 1.5;
  resize: none;
  max-height: 200px;
  padding: 8px 0;
}

.chat-input-wrapper textarea::placeholder {
  color: var(--text-tertiary);
}

.send-btn {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--text-primary);
  border: none;
  color: var(--bg-primary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: opacity 0.15s ease, transform 0.15s ease;
}

.send-btn:hover {
  opacity: 0.9;
}

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

.send-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.input-disclaimer {
  font-size: 12px;
  color: var(--text-tertiary);
  text-align: center;
  margin-top: 8px;
}

/* Typing indicator */
.typing-indicator {
  display: flex;
  gap: 4px;
  padding: 8px 0;
}

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

.typing-dot:nth-child(1) { animation-delay: -0.32s; }
.typing-dot:nth-child(2) { animation-delay: -0.16s; }
.typing-dot:nth-child(3) { animation-delay: 0; }

@keyframes typingBounce {
  0%, 80%, 100% {
    transform: scale(0.6);
    opacity: 0.4;
  }
  40% {
    transform: scale(1);
    opacity: 1;
  }
}

/* Mobile Responsive */
@media (max-width: 768px) {
  .sidebar {
    position: fixed;
    left: 0;
    top: 0;
    bottom: 0;
    z-index: 100;
    transform: translateX(-100%);
  }
  
  .sidebar.open {
    transform: translateX(0);
  }
  
  .mobile-menu-btn {
    display: flex;
  }
  
  .chat-header {
    justify-content: flex-start;
    gap: 12px;
  }
  
  .header-spacer {
    display: none;
  }
  
  .message {
    padding: 12px 16px;
  }
  
  .chat-input-container {
    padding: 12px 16px 16px;
  }
  
  .welcome-suggestions {
    grid-template-columns: 1fr;
  }
}

/* Sidebar overlay for mobile */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.5);
  z-index: 99;
}

.sidebar-overlay.visible {
  display: block;
}

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

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

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

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

/* Selection */
::selection {
  background: var(--accent);
  color: white;
}