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

:root {
  --primary-color: #667eea;
  --secondary-color: #764ba2;
  --bg-color: #0f0f1e;
  --surface-color: #1a1a2e;
  --text-color: #e0e0e0;
  --text-secondary: #a0a0a0;
  --border-color: #2d2d44;
  --success-color: #10b981;
  --danger-color: #ef4444;
  --user-msg-bg: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --assistant-msg-bg: #252539;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Oxygen",
    "Ubuntu", "Cantarell", sans-serif;
  background: var(--bg-color);
  color: var(--text-color);
  height: 100vh;
  overflow: hidden;
}

.screen {
  width: 100%;
  height: 100vh;
}

.hidden {
  display: none !important;
}

/* Login Screen */
.login-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  height: 100vh;
  background: linear-gradient(
    135deg,
    var(--primary-color) 0%,
    var(--secondary-color) 100%
  );
}

.login-container h1 {
  font-size: 3rem;
  margin-bottom: 0.5rem;
  color: white;
}

.subtitle {
  font-size: 1.2rem;
  color: rgba(255, 255, 255, 0.9);
  margin-bottom: 3rem;
}

.google-btn {
  display: flex;
  align-items: center;
  gap: 12px;
  background: white;
  color: #333;
  padding: 12px 24px;
  border: none;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.google-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
}

/* Main App Container */
.app-container {
  display: flex;
  height: 100vh;
}

/* Sidebar */
.sidebar {
  width: 280px;
  background: var(--surface-color);
  border-right: 1px solid var(--border-color);
  display: flex;
  flex-direction: column;
}

.sidebar-header {
  padding: 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.sidebar-header h2 {
  font-size: 1.5rem;
  margin-bottom: 1rem;
  background: linear-gradient(
    135deg,
    var(--primary-color) 0%,
    var(--secondary-color) 100%
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.new-chat-btn {
  width: 100%;
  padding: 10px;
  background: linear-gradient(
    135deg,
    var(--primary-color) 0%,
    var(--secondary-color) 100%
  );
  color: white;
  border: none;
  border-radius: 8px;
  font-size: 0.95rem;
  font-weight: 500;
  cursor: pointer;
  transition: opacity 0.2s;
}

.new-chat-btn:hover {
  opacity: 0.9;
}

.model-selector {
  padding: 1rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.model-selector label {
  display: block;
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 0.5rem;
}

.model-helper-text {
  margin-top: 0.5rem;
  font-size: 0.75rem;
  color: var(--text-secondary);
  opacity: 0.7;
}

.model-select-list {
  background: transparent;
  max-height: 280px;
  overflow-y: auto;
  margin-top: 0.5rem;
}

.model-select-list::-webkit-scrollbar {
  width: 6px;
}

.model-select-list::-webkit-scrollbar-track {
  background: transparent;
}

.model-select-list::-webkit-scrollbar-thumb {
  background: var(--border-color);
  border-radius: 3px;
}

.model-select-list::-webkit-scrollbar-thumb:hover {
  background: var(--text-secondary);
}

.model-group {
  margin-bottom: 0.75rem;
}

.model-group:last-child {
  margin-bottom: 0;
}

.model-group-label {
  font-size: 0.7rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 1px;
  padding: 0 0.25rem 0.35rem;
  font-weight: 600;
  opacity: 0.7;
}

.model-item {
  display: flex;
  align-items: center;
  padding: 0.4rem 0.5rem;
  cursor: pointer;
  transition: all 0.15s ease;
  border-radius: 6px;
  margin-bottom: 2px;
}

.model-item:hover {
  background: rgba(102, 126, 234, 0.08);
  transform: translateX(2px);
}

.model-item input[type="checkbox"] {
  margin: 0;
  margin-right: 0.65rem;
  cursor: pointer;
  width: 17px;
  height: 17px;
  accent-color: var(--primary-color);
  flex-shrink: 0;
}

.model-item label {
  cursor: pointer;
  font-size: 0.88rem;
  flex: 1;
  user-select: none;
  font-weight: 400;
  color: var(--text-color);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.capability-icons {
  display: inline-flex;
  gap: 4px;
  margin-left: auto;
  opacity: 0.5;
}

.capability-icons .cap-icon {
  width: 14px;
  height: 14px;
  display: inline-flex;
  align-items: center;
}

.capability-icons .cap-icon svg {
  width: 14px;
  height: 14px;
  stroke: currentColor;
  stroke-width: 2;
  fill: none;
}

.model-item:hover .capability-icons {
  opacity: 0.8;
}

.custom-badge {
  display: inline-block;
  padding: 0.15rem 0.4rem;
  background: rgba(102, 126, 234, 0.2);
  border: 1px solid rgba(102, 126, 234, 0.4);
  border-radius: 4px;
  color: var(--primary-color);
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

/* Chat History */
.chat-history {
  flex: 1;
  overflow-y: auto;
  padding: 1rem 1.5rem;
}

.chat-history h3 {
  font-size: 0.85rem;
  color: var(--text-secondary);
  margin-bottom: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.chat-history-list {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.chat-history-item {
  padding: 10px;
  background: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.2s;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.chat-history-item:hover {
  background: rgba(102, 126, 234, 0.1);
  border-color: var(--primary-color);
}

.chat-history-item.active {
  background: rgba(102, 126, 234, 0.2);
  border-color: var(--primary-color);
}

.chat-title {
  font-size: 0.9rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.delete-chat-btn {
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 4px;
  display: none;
}

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

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

/* Sidebar Footer */
.sidebar-footer {
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--border-color);
}

.user-info {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 1rem;
}

.user-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
}

.user-name {
  font-size: 0.9rem;
  color: var(--text-color);
}

.sign-out-btn {
  width: 100%;
  padding: 8px;
  background: transparent;
  color: var(--danger-color);
  border: 1px solid var(--danger-color);
  border-radius: 6px;
  cursor: pointer;
  transition: all 0.2s;
}

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

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

.chat-messages {
  flex: 1;
  overflow-y: auto;
  padding: 2rem;
}

/* Welcome Message */
.welcome-message {
  text-align: center;
  padding: 4rem 2rem;
}

.welcome-message h1 {
  font-size: 2.5rem;
  margin-bottom: 1rem;
  background: linear-gradient(
    135deg,
    var(--primary-color) 0%,
    var(--secondary-color) 100%
  );
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.welcome-message > p {
  font-size: 1.2rem;
  color: var(--text-secondary);
  margin-bottom: 3rem;
}

.model-info {
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
  max-width: 900px;
  margin: 0 auto;
}

.model-card {
  background: var(--surface-color);
  padding: 2rem;
  border-radius: 12px;
  border: 1px solid var(--border-color);
  min-width: 200px;
}

.model-card h3 {
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
  color: var(--primary-color);
}

.model-card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
}

/* Chat Messages */
.message {
  display: flex;
  gap: 1rem;
  margin-bottom: 1.5rem;
  animation: fadeIn 0.3s ease;
}

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

.message-avatar {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: bold;
  font-size: 0.9rem;
}

.message.user .message-avatar {
  background: var(--user-msg-bg);
  color: white;
}

.message.assistant .message-avatar {
  background: var(--assistant-msg-bg);
  color: var(--primary-color);
}

.message-content {
  flex: 1;
  max-width: 800px;
}

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

.message-role {
  font-weight: 600;
  font-size: 0.9rem;
}

.message-model {
  font-size: 0.75rem;
  color: var(--text-secondary);
  background: var(--surface-color);
  padding: 2px 8px;
  border-radius: 4px;
}

.message-text {
  line-height: 1.6;
  font-size: 0.95rem;
  word-wrap: break-word;
}

.comparison-badge {
  background: rgba(102, 126, 234, 0.15);
  color: var(--primary-color);
  border: 1px solid var(--primary-color);
}

.message-content:has(.comparison-wrapper) {
  max-width: 100%;
}

.comparison-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 14px;
  width: 100%;
}

.comparison-grid.comparison-cols-2 {
  grid-template-columns: repeat(2, 1fr);
}

.comparison-card {
  background: var(--assistant-msg-bg);
  border: 1px solid var(--border-color);
  border-radius: 10px;
  padding: 14px;
  display: flex;
  flex-direction: column;
  min-width: 0;
}

.comparison-card-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--border-color);
  gap: 8px;
}

.comparison-model {
  font-weight: 600;
  font-size: 0.85rem;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  min-width: 0;
}

.comparison-card-body {
  line-height: 1.6;
  font-size: 0.9rem;
  word-wrap: break-word;
  overflow-wrap: break-word;
  max-height: 500px;
  overflow-y: auto;
  flex: 1;
}

.comparison-card-body pre {
  overflow-x: auto;
  max-width: 100%;
}

.comparison-card-body pre code {
  font-size: 0.8rem;
  white-space: pre;
  word-break: normal;
  overflow-wrap: normal;
}

.comparison-usage {
  display: flex;
  gap: 10px;
  align-items: center;
  margin-top: 12px;
  padding-top: 8px;
  border-top: 1px solid var(--border-color);
  font-size: 0.78rem;
  color: var(--text-secondary);
  flex-wrap: wrap;
}

@media (max-width: 768px) {
  .comparison-grid {
    grid-template-columns: 1fr;
  }
}

/* Judge Bar */
.judge-bar {
  display: flex;
  gap: 8px;
  align-items: center;
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--border-color);
}

.judge-model-select {
  background: var(--surface-color);
  color: var(--text-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 6px 10px;
  font-size: 0.85rem;
  flex: 1;
  max-width: 220px;
}

.btn-judge {
  background: rgba(102, 126, 234, 0.15);
  color: var(--primary-color);
  border: 1px solid var(--primary-color);
  border-radius: 6px;
  padding: 6px 14px;
  font-size: 0.85rem;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.2s;
}
.btn-judge:hover { background: rgba(102, 126, 234, 0.25); }
.btn-judge:disabled { opacity: 0.5; cursor: wait; }

/* Judge Verdict Panel */
.judge-verdict-panel {
  margin-top: 12px;
  padding: 16px;
  background: var(--assistant-msg-bg);
  border: 1px solid var(--primary-color);
  border-radius: 10px;
}

.judge-verdict-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}
.judge-verdict-title { font-weight: 700; font-size: 1rem; color: var(--primary-color); }
.judge-verdict-model { font-size: 0.8rem; color: var(--text-secondary); }
.judge-verdict-cost { font-size: 0.8rem; color: var(--text-secondary); margin-left: auto; }

/* Ranking */
.judge-ranking {
  display: flex;
  gap: 16px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}
.judge-ranking-item { display: flex; align-items: center; gap: 6px; }
.rank-number { font-weight: 700; font-size: 1rem; }
.rank-model { font-size: 0.9rem; color: var(--text-color); }

/* Score Table */
.judge-scores-table {
  width: 100%;
  border-collapse: collapse;
  margin-bottom: 14px;
  font-size: 0.85rem;
}
.judge-scores-table th, .judge-scores-table td {
  padding: 6px 10px;
  text-align: center;
  border-bottom: 1px solid var(--border-color);
}
.judge-scores-table th { color: var(--text-secondary); font-weight: 600; }
.judge-scores-table td:first-child, .judge-scores-table th:first-child { text-align: left; }
.score-high { color: #4caf50; font-weight: 600; }
.score-mid { color: #ff9800; }
.score-low { color: #f44336; }

/* Per-model Analysis */
.judge-model-analysis {
  padding: 8px 0;
  border-bottom: 1px solid var(--border-color);
}
.judge-model-analysis:last-of-type { border-bottom: none; }
.judge-analysis-model { font-weight: 600; margin-bottom: 4px; color: var(--text-color); }
.judge-analysis-detail { font-size: 0.85rem; color: var(--text-secondary); margin-bottom: 2px; }

/* Summary */
.judge-summary {
  margin-top: 12px;
  padding-top: 10px;
  border-top: 1px solid var(--border-color);
  font-size: 0.9rem;
  color: var(--text-color);
  line-height: 1.5;
}

.message.user .message-text {
  background: var(--user-msg-bg);
  padding: 12px 16px;
  border-radius: 12px;
  color: white;
  white-space: pre-wrap;
}

.message.assistant .message-text {
  background: var(--assistant-msg-bg);
  padding: 12px 16px;
  border-radius: 12px;
}

/* Usage Info (tokens and cost) */
.message-usage {
  display: flex;
  gap: 12px;
  margin-top: 8px;
  font-size: 0.75rem;
  color: var(--text-secondary);
  opacity: 0.8;
}

.usage-tokens,
.usage-cost {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: var(--surface-color);
  padding: 2px 8px;
  border-radius: 4px;
}

.usage-cost {
  color: var(--primary-color);
  font-weight: 500;
}

/* Chat Input */
.chat-input-container {
  padding: 1.5rem;
  border-top: 1px solid var(--border-color);
  background: var(--surface-color);
}

.chat-input-wrapper {
  display: flex;
  gap: 1rem;
  max-width: 900px;
  margin: 0 auto;
  align-items: flex-end;
}

.chat-input {
  flex: 1;
  padding: 12px 16px;
  background: var(--bg-color);
  color: var(--text-color);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  font-size: 0.95rem;
  font-family: inherit;
  resize: none;
  max-height: 200px;
  overflow-y: auto;
}

.chat-input:focus {
  outline: none;
  border-color: var(--primary-color);
}

.send-btn {
  padding: 12px;
  background: linear-gradient(
    135deg,
    var(--primary-color) 0%,
    var(--secondary-color) 100%
  );
  color: white;
  border: none;
  border-radius: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: opacity 0.2s;
  width: 48px;
  height: 48px;
}

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

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

/* Loading Indicator */
.loading-indicator {
  position: fixed;
  bottom: 100px;
  right: 50px;
  background: var(--surface-color);
  padding: 1rem 1.5rem;
  border-radius: 12px;
  border: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 1rem;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

.spinner {
  width: 20px;
  height: 20px;
  border: 2px solid var(--border-color);
  border-top-color: var(--primary-color);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

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

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

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

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

/* Responsive */
@media (max-width: 768px) {
  .sidebar {
    width: 100%;
    max-width: 280px;
    position: absolute;
    left: -100%;
    z-index: 100;
    transition: left 0.3s;
  }

  .sidebar.open {
    left: 0;
  }

  .model-info {
    flex-direction: column;
    gap: 1rem;
  }
}

/* Character Counter */
.char-counter {
  font-size: 0.75rem;
  color: var(--text-secondary);
  text-align: right;
  padding: 0.25rem 0.5rem;
  opacity: 0.7;
}

.char-counter.near-limit {
  color: #f59e0b;
  opacity: 1;
}

.char-counter.over-limit {
  color: #ef4444;
  opacity: 1;
  font-weight: 500;
}

/* Notification System */
.notification {
  position: fixed;
  top: 20px;
  right: 20px;
  padding: 12px 20px;
  border-radius: 8px;
  font-size: 0.9rem;
  z-index: 1000;
  animation: notification-slide-in 0.3s ease-out;
  max-width: 400px;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

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

.notification-warning {
  background: #f59e0b;
  color: #1a1a1a;
}

.notification-error {
  background: #ef4444;
  color: white;
}

.notification-success {
  background: #10b981;
  color: white;
}

.notification-fade-out {
  animation: notification-fade-out 0.3s ease-out forwards;
}

@keyframes notification-slide-in {
  from {
    transform: translateX(100%);
    opacity: 0;
  }
  to {
    transform: translateX(0);
    opacity: 1;
  }
}

@keyframes notification-fade-out {
  from {
    transform: translateX(0);
    opacity: 1;
  }
  to {
    transform: translateX(100%);
    opacity: 0;
  }
}

/* =====================================================
   PHASE 3: UX ENHANCEMENTS
   ===================================================== */

/* Chat Search */
.chat-history-header {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin-bottom: 0.5rem;
}

.chat-history-header h3 {
  margin: 0;
}

.search-container {
  position: relative;
}

.chat-search {
  width: 100%;
  padding: 0.5rem 0.75rem;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  background: var(--input-bg);
  color: var(--text-color);
  font-size: 0.85rem;
  transition: border-color 0.2s, box-shadow 0.2s;
}

.chat-search:focus {
  outline: none;
  border-color: var(--primary-color);
  box-shadow: 0 0 0 2px rgba(139, 92, 246, 0.2);
}

.chat-search::placeholder {
  color: var(--text-secondary);
}

/* Copy Buttons */
.copy-message-btn,
.copy-code-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 4px;
  border-radius: 4px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color 0.2s, background 0.2s;
  opacity: 0;
}

.message:hover .copy-message-btn,
.code-block-wrapper:hover .copy-code-btn {
  opacity: 1;
}

.copy-message-btn:hover,
.copy-code-btn:hover {
  color: var(--text-color);
  background: var(--border-color);
}

.copy-message-btn.copied,
.copy-code-btn.copied {
  color: #10b981;
}

.message-header {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.message-header .copy-message-btn {
  margin-left: auto;
}

/* Sticky copy button for assistant messages - scrolls with the response */
.message.assistant .message-header {
  position: sticky;
  top: 0;
  background: var(--bg-color);
  padding: 8px 0;
  z-index: 10;
  margin-bottom: 0.5rem;
}

.message.assistant .copy-message-btn {
  opacity: 1;
  background: var(--surface-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  padding: 6px;
}

.message.assistant .copy-message-btn:hover {
  background: var(--border-color);
}

/* Code Block Styling */
.code-block-wrapper {
  position: relative;
  margin: 1rem 0;
}

.code-block-wrapper .copy-code-btn {
  position: absolute;
  top: 8px;
  right: 8px;
  background: rgba(0, 0, 0, 0.5);
  padding: 6px;
  z-index: 10;
}

.code-block-wrapper .copy-code-btn:hover {
  background: rgba(0, 0, 0, 0.7);
}

.message-text pre.hljs {
  margin: 0;
  padding: 1rem;
  border-radius: 8px;
  overflow-x: auto;
  background: #0d1117 !important;
}

.message-text code {
  font-family: "JetBrains Mono", "Fira Code", "Consolas", monospace;
  font-size: 0.9em;
}

.message-text :not(pre) > code {
  background: rgba(110, 118, 129, 0.3);
  padding: 0.2em 0.4em;
  border-radius: 4px;
  font-size: 0.85em;
}

/* Markdown Content Styling */
.message-text h1,
.message-text h2,
.message-text h3,
.message-text h4 {
  margin-top: 1.5rem;
  margin-bottom: 0.5rem;
  color: var(--text-color);
}

.message-text h1:first-child,
.message-text h2:first-child,
.message-text h3:first-child {
  margin-top: 0;
}

.message-text p {
  margin: 0.75rem 0;
  line-height: 1.6;
}

.message-text p:first-child {
  margin-top: 0;
}

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

.message-text ul,
.message-text ol {
  margin: 0.75rem 0;
  padding-left: 1.5rem;
}

.message-text li {
  margin: 0.25rem 0;
  line-height: 1.5;
}

.message-text blockquote {
  margin: 1rem 0;
  padding: 0.5rem 1rem;
  border-left: 4px solid var(--primary-color);
  background: rgba(139, 92, 246, 0.1);
  border-radius: 0 4px 4px 0;
}

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

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

.message-text hr {
  border: none;
  border-top: 1px solid var(--border-color);
  margin: 1.5rem 0;
}

.message-text table {
  border-collapse: collapse;
  width: 100%;
  margin: 1rem 0;
}

.message-text th,
.message-text td {
  border: 1px solid var(--border-color);
  padding: 0.5rem 0.75rem;
  text-align: left;
}

.message-text th {
  background: var(--sidebar-bg);
}

/* Generated Images Styling */
.message-text img {
  max-width: 500px;
  max-height: 400px;
  width: auto;
  height: auto;
  object-fit: contain;
  border-radius: 8px;
  margin: 1rem 0;
  display: block;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

/* Keyboard Shortcuts Modal */
.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.7);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
  backdrop-filter: blur(4px);
}

.modal.hidden {
  display: none;
}

.modal-content {
  background: var(--card-bg);
  border-radius: 12px;
  width: 90%;
  max-width: 500px;
  max-height: 80vh;
  overflow-y: auto;
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.5);
  animation: modal-appear 0.2s ease-out;
}

@keyframes modal-appear {
  from {
    transform: scale(0.95);
    opacity: 0;
  }
  to {
    transform: scale(1);
    opacity: 1;
  }
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1.25rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.modal-header h2 {
  margin: 0;
  font-size: 1.25rem;
}

.modal-close {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0;
  line-height: 1;
  transition: color 0.2s;
}

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

.modal-body {
  padding: 1.5rem;
}

.shortcut-group {
  margin-bottom: 1.5rem;
}

.shortcut-group:last-child {
  margin-bottom: 0;
}

.shortcut-group h3 {
  font-size: 0.85rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.5px;
  margin: 0 0 0.75rem 0;
}

.shortcut {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0;
  color: var(--text-color);
  font-size: 0.9rem;
}

kbd {
  display: inline-block;
  padding: 0.25rem 0.5rem;
  font-size: 0.8rem;
  font-family: inherit;
  background: var(--sidebar-bg);
  border: 1px solid var(--border-color);
  border-radius: 4px;
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

/* Mobile Sidebar Toggle Button */
.sidebar-toggle {
  display: none;
  position: fixed;
  top: 1rem;
  left: 1rem;
  z-index: 101;
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 0.75rem;
  cursor: pointer;
  color: var(--text-color);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.2);
}

.sidebar-toggle:hover {
  background: var(--sidebar-bg);
}

/* Mobile Overlay */
.sidebar-overlay {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  z-index: 99;
}

/* Enhanced Mobile Responsive */
@media (max-width: 768px) {
  .sidebar-toggle {
    display: flex;
  }

  .sidebar {
    position: fixed;
    top: 0;
    left: -100%;
    height: 100%;
    width: 280px;
    max-width: 85%;
    z-index: 100;
    transition: left 0.3s ease;
    box-shadow: 4px 0 20px rgba(0, 0, 0, 0.3);
  }

  .sidebar.open {
    left: 0;
  }

  .sidebar.open ~ .sidebar-overlay {
    display: block;
  }

  .chat-main {
    padding-top: 4rem;
  }

  .welcome-message h1 {
    font-size: 1.5rem;
  }

  .model-info {
    flex-direction: column;
  }

  .model-card {
    width: 100%;
  }
}

/* Accessibility: Focus Styles */
button:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline: 2px solid var(--primary-color);
  outline-offset: 2px;
}

/* Print Styles */
@media print {
  .sidebar,
  .chat-input-container,
  .loading-indicator,
  .copy-message-btn,
  .copy-code-btn {
    display: none !important;
  }

  .chat-main {
    width: 100%;
  }

  .message {
    page-break-inside: avoid;
  }
}

/* =====================================================
   PHASE 4: FEATURE ADDITIONS
   ===================================================== */

/* Light Theme Variables */
[data-theme="light"] {
  --bg-color: #f5f5f5;
  --surface-color: #ffffff;
  --text-color: #1a1a2e;
  --text-secondary: #666;
  --border-color: #e0e0e0;
  --assistant-msg-bg: #f0f0f5;
}

/* System Prompt Section */
.system-prompt-section {
  padding: 0 1.5rem;
  border-bottom: 1px solid var(--border-color);
}

.toggle-section-btn {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.75rem 0;
  background: none;
  border: none;
  color: var(--text-secondary);
  font-size: 0.85rem;
  cursor: pointer;
  transition: color 0.2s;
}

.toggle-section-btn:hover {
  color: var(--text-color);
}

.toggle-section-btn svg {
  transition: transform 0.2s;
}

.toggle-section-btn.expanded svg {
  transform: rotate(180deg);
}

.collapsible-content {
  padding-bottom: 1rem;
}

.system-prompt-input {
  width: 100%;
  padding: 0.75rem;
  background: var(--bg-color);
  color: var(--text-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 0.85rem;
  font-family: inherit;
  resize: vertical;
  min-height: 80px;
  max-height: 200px;
}

.system-prompt-input:focus {
  outline: none;
  border-color: var(--primary-color);
}

.system-prompt-presets {
  margin-top: 0.5rem;
}

.prompt-presets-select {
  width: 100%;
  padding: 0.5rem;
  background: var(--bg-color);
  color: var(--text-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 0.8rem;
  cursor: pointer;
}

/* Footer Buttons */
.footer-buttons {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 1rem;
}

.footer-buttons .theme-toggle {
  flex: 1;
  margin-bottom: 0;
}

.stats-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.75rem;
  background: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: var(--text-color);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.2s;
}

.stats-btn:hover {
  border-color: var(--primary-color);
}

/* Theme Toggle */
.theme-toggle {
  margin-bottom: 1rem;
}

.theme-toggle-btn {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.75rem;
  background: var(--bg-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: var(--text-color);
  font-size: 0.85rem;
  cursor: pointer;
  transition: all 0.2s;
  width: 100%;
}

.theme-toggle-btn:hover {
  border-color: var(--primary-color);
}

.theme-toggle-btn svg {
  flex-shrink: 0;
}

/* Chat Toolbar */
.chat-toolbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 0.75rem 1.5rem;
  border-bottom: 1px solid var(--border-color);
  background: var(--surface-color);
}

.toolbar-left {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex: 1;
  min-width: 0;
}

.chat-title-display {
  font-weight: 500;
  font-size: 0.95rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.message-count {
  font-size: 0.8rem;
  color: var(--text-secondary);
  white-space: nowrap;
}

.toolbar-right {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.toolbar-btn {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  padding: 0.5rem 0.75rem;
  background: transparent;
  border: 1px solid var(--border-color);
  border-radius: 6px;
  color: var(--text-secondary);
  font-size: 0.75rem;
  cursor: pointer;
  transition: all 0.2s;
}

.toolbar-btn:hover {
  color: var(--text-color);
  border-color: var(--primary-color);
  background: rgba(102, 126, 234, 0.1);
}

/* Edit Message Modal */
.modal-edit {
  max-width: 600px;
}

.edit-message-textarea {
  width: 100%;
  padding: 1rem;
  background: var(--bg-color);
  color: var(--text-color);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  font-size: 0.95rem;
  font-family: inherit;
  resize: vertical;
  min-height: 150px;
  line-height: 1.5;
}

.edit-message-textarea:focus {
  outline: none;
  border-color: var(--primary-color);
}

.edit-message-note {
  margin-top: 0.75rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.modal-footer {
  display: flex;
  justify-content: flex-end;
  gap: 0.75rem;
  padding: 1rem 1.5rem;
  border-top: 1px solid var(--border-color);
}

.btn {
  padding: 0.6rem 1.25rem;
  border-radius: 6px;
  font-size: 0.9rem;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s;
}

.btn-secondary {
  background: transparent;
  border: 1px solid var(--border-color);
  color: var(--text-color);
}

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

.btn-primary {
  background: linear-gradient(
    135deg,
    var(--primary-color) 0%,
    var(--secondary-color) 100%
  );
  border: none;
  color: white;
}

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

/* Message Edit Button */
.edit-message-btn {
  background: transparent;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 4px;
  border-radius: 4px;
  opacity: 0;
  transition: all 0.2s;
}

.message.user:hover .edit-message-btn {
  opacity: 1;
}

.edit-message-btn:hover {
  color: var(--primary-color);
  background: rgba(102, 126, 234, 0.1);
}

/* Stats Modal */
.stats-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1rem;
  margin-bottom: 1.5rem;
}

.stat-card {
  background: var(--bg-color);
  padding: 1.25rem;
  border-radius: 8px;
  text-align: center;
}

.stat-value {
  font-size: 1.75rem;
  font-weight: 600;
  color: var(--primary-color);
  margin-bottom: 0.25rem;
}

.stat-label {
  font-size: 0.8rem;
  color: var(--text-secondary);
}

.stats-chart h3 {
  font-size: 0.9rem;
  margin-bottom: 1rem;
  color: var(--text-color);
}

.usage-chart {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

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

.usage-bar-label {
  width: 100px;
  font-size: 0.8rem;
  color: var(--text-secondary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.usage-bar-track {
  flex: 1;
  height: 8px;
  background: var(--border-color);
  border-radius: 4px;
  overflow: hidden;
}

.usage-bar-fill {
  height: 100%;
  background: linear-gradient(
    135deg,
    var(--primary-color) 0%,
    var(--secondary-color) 100%
  );
  border-radius: 4px;
  transition: width 0.3s ease;
}

.usage-bar-count {
  width: 30px;
  font-size: 0.8rem;
  color: var(--text-color);
  text-align: right;
}

/* Mobile adjustments for Phase 4 */
@media (max-width: 768px) {
  .stats-grid {
    grid-template-columns: 1fr;
  }

  .chat-toolbar {
    flex-direction: column;
    gap: 0.5rem;
    align-items: flex-start;
  }

  .toolbar-right {
    width: 100%;
    justify-content: flex-end;
  }
}

/* ============================================================
   Image Upload & Preview
   ============================================================ */

.upload-btn {
  padding: 8px;
  background: transparent;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
  flex-shrink: 0;
}

.upload-btn:hover {
  color: var(--primary-color);
  border-color: var(--primary-color);
  background: rgba(99, 102, 241, 0.05);
}

.image-preview-area {
  display: flex;
  gap: 8px;
  padding: 8px 0;
  max-width: 900px;
  margin: 0 auto;
  flex-wrap: wrap;
}

.image-preview-area.hidden {
  display: none;
}

.image-thumbnail {
  position: relative;
  width: 60px;
  height: 60px;
  border-radius: 8px;
  overflow: hidden;
  border: 1px solid var(--border-color);
  flex-shrink: 0;
}

.image-thumbnail img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.image-thumbnail .remove-btn {
  position: absolute;
  top: 2px;
  right: 2px;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.6);
  color: #fff;
  border: none;
  font-size: 12px;
  line-height: 18px;
  text-align: center;
  cursor: pointer;
  padding: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}

.image-thumbnail .remove-btn:hover {
  background: rgba(220, 38, 38, 0.8);
}

.chat-input-wrapper.drag-over {
  outline: 2px dashed var(--primary-color);
  outline-offset: -2px;
  background: rgba(99, 102, 241, 0.05);
}

/* Images displayed in messages */
.message-images {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-bottom: 8px;
}

.message-images img {
  max-width: 200px;
  max-height: 200px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  object-fit: contain;
  cursor: pointer;
}

.message-images img:hover {
  opacity: 0.9;
}

/* ============================================================
   Image Lightbox
   ============================================================ */

.image-lightbox {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.85);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 2000;
  cursor: pointer;
}

.image-lightbox.hidden {
  display: none;
}

#lightboxImage {
  max-width: 90vw;
  max-height: 90vh;
  object-fit: contain;
  border-radius: 8px;
  cursor: default;
}

.lightbox-close {
  position: absolute;
  top: 1rem;
  right: 1.5rem;
  background: transparent;
  border: none;
  color: white;
  font-size: 2rem;
  cursor: pointer;
  line-height: 1;
  z-index: 2001;
  padding: 0.25rem 0.5rem;
  border-radius: 4px;
  transition: background 0.2s;
}

.lightbox-close:hover {
  background: rgba(255, 255, 255, 0.15);
}

/* Make images in messages clickable */
.message-text img {
  cursor: pointer;
}

/* ============================================================
   Document Upload & Preview
   ============================================================ */

.doc-upload-btn {
  /* Inherits from .upload-btn */
}

.document-preview-area {
  display: flex;
  gap: 8px;
  padding: 8px 0;
  max-width: 900px;
  margin: 0 auto;
  flex-wrap: wrap;
}

.document-preview-area.hidden {
  display: none;
}

.document-chip {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 10px;
  background: var(--surface-color);
  border: 1px solid var(--border-color);
  border-radius: 6px;
  font-size: 0.8rem;
  color: var(--text-color);
  max-width: 200px;
}

.document-chip .doc-icon {
  flex-shrink: 0;
  color: var(--primary-color);
}

.document-chip .doc-name {
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.document-chip .remove-btn {
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  font-size: 14px;
  padding: 0 2px;
  line-height: 1;
  flex-shrink: 0;
}

.document-chip .remove-btn:hover {
  color: var(--danger-color);
}

/* Document indicator in user messages */
.message-documents {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
  margin-bottom: 6px;
}

.message-doc-badge {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 3px 8px;
  background: rgba(102, 126, 234, 0.15);
  border: 1px solid rgba(102, 126, 234, 0.3);
  border-radius: 4px;
  font-size: 0.75rem;
  color: var(--primary-color);
}

.message-doc-badge svg {
  flex-shrink: 0;
}

/* ============================================================
   Judge Enhancements: Response Time + Suggest & Test
   ============================================================ */

/* Response time badge in comparison cards */
.usage-time {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  background: rgba(76, 175, 80, 0.15);
  color: #4caf50;
  font-weight: 600;
  padding: 2px 8px;
  border-radius: 4px;
}

/* Suggest & Test button */
.btn-suggest {
  background: rgba(76, 175, 80, 0.15);
  color: #4caf50;
  border: 1px solid #4caf50;
  border-radius: 6px;
  padding: 6px 14px;
  font-size: 0.85rem;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.2s;
}
.btn-suggest:hover { background: rgba(76, 175, 80, 0.25); }
.btn-suggest:disabled { opacity: 0.5; cursor: wait; }

/* Suggestions container */
.suggestions-container {
  margin-top: 12px;
  padding-top: 12px;
  border-top: 1px solid var(--border-color);
}

.suggestions-header {
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--text-color);
  margin-bottom: 10px;
}

/* Individual suggestion card */
.suggestion-card {
  background: var(--surface-color);
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 12px 14px;
  margin-bottom: 8px;
  cursor: pointer;
  transition: all 0.2s ease;
}

.suggestion-card:hover {
  border-color: var(--primary-color);
  background: rgba(102, 126, 234, 0.05);
  transform: translateX(2px);
}

.suggestion-card.suggestion-used {
  opacity: 0.5;
  cursor: default;
  pointer-events: none;
}

.suggestion-question {
  font-size: 0.9rem;
  color: var(--text-color);
  margin-bottom: 4px;
  line-height: 1.4;
}

.suggestion-rationale {
  font-size: 0.8rem;
  color: var(--text-secondary);
  font-style: italic;
  line-height: 1.3;
}

/* ============================================================
   Standalone Suggest & Test Button + UI
   ============================================================ */

.suggest-test-btn {
  padding: 8px;
  background: transparent;
  border: 1px solid #4caf50;
  border-radius: 8px;
  color: #4caf50;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
  flex-shrink: 0;
}

.suggest-test-btn:hover {
  background: rgba(76, 175, 80, 0.1);
}

.suggest-test-btn:disabled {
  opacity: 0.5;
  cursor: wait;
}

/* Standalone suggestions message block */
.standalone-suggestions {
  max-width: 800px;
}

.standalone-suggestions-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
  flex-wrap: wrap;
}

.standalone-suggestions-header .message-role {
  font-weight: 700;
  font-size: 0.95rem;
}

.standalone-suggestions-header .judge-model-select {
  margin-left: auto;
}

/* Image thumbnail on suggestion cards */
.suggestion-image-preview {
  width: 80px;
  height: 60px;
  object-fit: cover;
  border-radius: 6px;
  border: 1px solid var(--border-color);
  margin-bottom: 6px;
  display: block;
}

/* ============================================================
   Mobile responsiveness (2026-06-11)
   Root fix for horizontal overflow on phones + small-screen polish.
   ============================================================ */

/* Flex children must be allowed to shrink below their content's
   intrinsic width — otherwise one wide descendant (a code block or a
   long unbroken string) forces the whole column past the viewport. */
.chat-main,
.chat-messages,
.chat-input-wrapper,
.chat-input,
.message,
.message-content,
.message-text,
.comparison-card {
  min-width: 0;
}

/* Long words / URLs wrap; code blocks scroll within their own box. */
.message-text {
  overflow-wrap: anywhere;
}
.message-text pre,
.comparison-card-body pre {
  max-width: 100%;
  overflow-x: auto;
}

@media (max-width: 768px) {
  html,
  body {
    overflow-x: hidden;
  }

  /* Reclaim horizontal space */
  .chat-messages {
    padding: 1rem 0.85rem;
  }
  .chat-input-container {
    padding: 0.75rem;
  }
  .chat-input-wrapper {
    gap: 0.5rem;
  }

  /* 16px input prevents iOS zoom-on-focus */
  .chat-input {
    font-size: 16px;
  }

  /* Comfortable tap targets */
  .send-btn {
    width: 46px;
    height: 46px;
  }
  .upload-btn,
  .suggest-test-btn,
  .toolbar-btn {
    min-height: 40px;
  }

  /* Sidebar drawer scrolls if the model list is tall */
  .sidebar {
    overflow-y: auto;
  }

  /* Model comparison stacks and never overflows */
  .comparison-grid,
  .comparison-grid.comparison-cols-2 {
    grid-template-columns: 1fr;
  }

  /* Modals fit the screen */
  .modal-content {
    width: calc(100% - 1.5rem);
    max-width: calc(100% - 1.5rem);
    max-height: 88vh;
    overflow-y: auto;
  }

  /* Float the API-console toggle above the input bar (was covering Send) */
  .console-toggle {
    bottom: 84px;
    right: 12px;
  }

  /* Hide the hamburger while the drawer is open (it overlapped the title) */
  body:has(.sidebar.open) .sidebar-toggle {
    display: none;
  }

  /* Footer buttons wrap instead of clipping "Stats" */
  .footer-buttons {
    flex-wrap: wrap;
    gap: 0.4rem;
  }
}

/* Very small phones */
@media (max-width: 380px) {
  .chat-messages {
    padding: 0.85rem 0.6rem;
  }
  .login-container h1 {
    font-size: 2.4rem;
  }
}