/* ════════════════════════════════════════════════
   Chat Arena — Styles
   Dark theme, glassmorphism, smooth animations
════════════════════════════════════════════════ */

:root {
  --bg-primary: #0a0a0f;
  --bg-secondary: #111118;
  --bg-card: #16161f;
  --bg-hover: #1e1e2a;
  --bg-input: #1a1a24;
  --border: #2a2a3a;
  --border-glow: #4f46e5;

  --text-primary: #f0f0fa;
  --text-secondary: #9090b0;
  --text-muted: #606080;

  --accent-1: #6366f1;   /* indigo  */
  --accent-2: #8b5cf6;   /* violet  */
  --accent-3: #06b6d4;   /* cyan    */
  --accent-4: #10b981;   /* emerald */

  /* Provider colors */
  --openai: #10a37f;
  --anthropic: #d4763b;
  --google: #4285f4;
  --mistral: #ff7000;

  --radius: 12px;
  --radius-lg: 20px;
  --shadow: 0 4px 24px rgba(0,0,0,0.4);
  --shadow-glow: 0 0 20px rgba(99, 102, 241, 0.15);
  --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);

  --sidebar-width: 280px;
  --header-height: 60px;
}

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

html, body {
  height: 100%;
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.6;
  overflow: hidden;
}

/* ── Scrollbar ─────────────────────────────────── */
::-webkit-scrollbar { width: 5px; height: 5px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 99px; }
::-webkit-scrollbar-thumb:hover { background: var(--accent-1); }

/* ── Layout ────────────────────────────────────── */
#app {
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* ── Auth Screen ───────────────────────────────── */
#auth-screen {
  position: fixed; inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  background: radial-gradient(ellipse at 50% 0%, rgba(99,102,241,0.12) 0%, transparent 65%),
              var(--bg-primary);
  z-index: 1000;
}

.auth-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 40px;
  width: 100%;
  max-width: 420px;
  box-shadow: var(--shadow), var(--shadow-glow);
}

.auth-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 28px;
  justify-content: center;
}

.auth-logo-icon {
  width: 44px; height: 44px;
  background: linear-gradient(135deg, var(--accent-1), var(--accent-2));
  border-radius: 12px;
  display: flex; align-items: center; justify-content: center;
  font-size: 22px;
}

.auth-logo-text { font-size: 22px; font-weight: 700; letter-spacing: -0.5px; }

.auth-tabs {
  display: flex;
  background: var(--bg-input);
  border-radius: 10px;
  padding: 4px;
  margin-bottom: 24px;
  gap: 4px;
}

.auth-tab {
  flex: 1;
  padding: 8px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font-size: 14px;
  font-weight: 500;
  border-radius: 7px;
  cursor: pointer;
  transition: var(--transition);
}

.auth-tab.active {
  background: var(--bg-card);
  color: var(--text-primary);
  box-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

.form-group { margin-bottom: 16px; }

.form-label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-secondary);
  margin-bottom: 6px;
}

.form-input {
  width: 100%;
  padding: 10px 14px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 14px;
  transition: var(--transition);
  outline: none;
}

.form-input:focus {
  border-color: var(--accent-1);
  box-shadow: 0 0 0 3px rgba(99,102,241,0.15);
}

.btn-primary {
  width: 100%;
  padding: 11px;
  background: linear-gradient(135deg, var(--accent-1), var(--accent-2));
  border: none;
  border-radius: 9px;
  color: white;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  position: relative;
  overflow: hidden;
  margin-top: 4px;
}

.btn-primary:hover { opacity: 0.9; transform: translateY(-1px); }
.btn-primary:active { transform: translateY(0); }
.btn-primary:disabled { opacity: 0.6; cursor: not-allowed; transform: none; }

.auth-error {
  color: #f87171;
  font-size: 13px;
  margin-top: 12px;
  text-align: center;
  min-height: 18px;
}

/* ── Sidebar ───────────────────────────────────── */
#sidebar {
  width: var(--sidebar-width);
  background: var(--bg-secondary);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  overflow: hidden;
}

.sidebar-header {
  padding: 16px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 10px;
  height: var(--header-height);
}

.logo-icon {
  width: 32px; height: 32px;
  background: linear-gradient(135deg, var(--accent-1), var(--accent-2));
  border-radius: 8px;
  display: flex; align-items: center; justify-content: center;
  font-size: 16px; flex-shrink: 0;
}

.logo-text { font-size: 16px; font-weight: 700; flex: 1; }

.btn-new-chat {
  padding: 6px 12px;
  background: linear-gradient(135deg, var(--accent-1), var(--accent-2));
  border: none;
  border-radius: 7px;
  color: white;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
}

.btn-new-chat:hover { opacity: 0.85; }

.sidebar-section-title {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.8px;
  padding: 12px 16px 6px;
}

.conversation-list {
  flex: 1;
  overflow-y: auto;
  padding: 4px 8px;
}

.conv-item {
  padding: 10px 10px;
  border-radius: 9px;
  cursor: pointer;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 8px;
  group: true;
}

.conv-item:hover { background: var(--bg-hover); }
.conv-item.active { background: rgba(99, 102, 241, 0.12); }

.conv-icon { font-size: 14px; flex-shrink: 0; }

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

.conv-title {
  font-size: 13px;
  font-weight: 500;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.conv-meta {
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 2px;
}

.conv-delete {
  opacity: 0;
  background: none;
  border: none;
  color: #f87171;
  cursor: pointer;
  padding: 3px 6px;
  border-radius: 5px;
  font-size: 13px;
  transition: var(--transition);
  flex-shrink: 0;
}

.conv-item:hover .conv-delete { opacity: 1; }
.conv-delete:hover { background: rgba(248, 113, 113, 0.12); }

.sidebar-footer {
  padding: 12px 16px;
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 10px;
}

.user-avatar {
  width: 30px; height: 30px;
  background: linear-gradient(135deg, var(--accent-3), var(--accent-1));
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  font-size: 13px; font-weight: 600; flex-shrink: 0;
  color: white;
}

.user-name {
  flex: 1;
  font-size: 13px;
  font-weight: 500;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.btn-icon {
  background: none;
  border: none;
  color: var(--text-secondary);
  cursor: pointer;
  padding: 6px;
  border-radius: 7px;
  transition: var(--transition);
  font-size: 16px;
  display: flex; align-items: center; justify-content: center;
}

.btn-icon:hover { background: var(--bg-hover); color: var(--text-primary); }

/* ── Main Area ─────────────────────────────────── */
#main {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--bg-primary);
}

/* ── Top Bar ───────────────────────────────────── */
#topbar {
  height: var(--header-height);
  padding: 0 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--bg-secondary);
  flex-shrink: 0;
}

.topbar-title {
  flex: 1;
  font-size: 15px;
  font-weight: 600;
  color: var(--text-secondary);
}

.model-selector-area {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

/* ── Model Pills ───────────────────────────────── */
.model-pill {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px 10px;
  border-radius: 99px;
  font-size: 12px;
  font-weight: 500;
  border: 1px solid var(--border);
  background: var(--bg-card);
  cursor: pointer;
  transition: var(--transition);
  white-space: nowrap;
}

.model-pill:hover { border-color: var(--accent-1); }
.model-pill.selected { border-color: var(--accent-1); background: rgba(99,102,241,0.12); color: #a5b4fc; }
.model-pill .provider-dot { width: 7px; height: 7px; border-radius: 50%; }
.model-pill .remove-btn { font-size: 11px; color: var(--text-muted); }

.btn-add-model {
  padding: 5px 10px;
  border: 1px dashed var(--border);
  border-radius: 99px;
  background: transparent;
  color: var(--text-muted);
  font-size: 12px;
  cursor: pointer;
  transition: var(--transition);
}

.btn-add-model:hover { border-color: var(--accent-1); color: var(--accent-1); }

/* ── Model Selector Dropdown ───────────────────── */
.model-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  right: 20px;
  width: 560px;
  max-height: 480px;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  overflow-y: auto;
  z-index: 500;
  padding: 8px;
}

.dropdown-provider-section { margin-bottom: 4px; }

.dropdown-provider-title {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.8px;
  padding: 8px 10px 4px;
  display: flex;
  align-items: center;
  gap: 8px;
}

.provider-badge {
  font-size: 10px;
  padding: 2px 7px;
  border-radius: 99px;
  font-weight: 600;
}

.provider-badge.no-key {
  background: rgba(248, 113, 113, 0.15);
  color: #f87171;
}

.provider-badge.has-key {
  background: rgba(16, 185, 129, 0.15);
  color: #34d399;
}

.model-option {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 10px;
  border-radius: 8px;
  cursor: pointer;
  transition: var(--transition);
}

.model-option:hover { background: var(--bg-hover); }
.model-option.selected { background: rgba(99,102,241,0.1); }

.model-option-dot { width: 8px; height: 8px; border-radius: 50%; flex-shrink: 0; }

.model-option-info { flex: 1; }
.model-option-name { font-size: 13px; font-weight: 500; }
.model-option-provider { font-size: 11px; color: var(--text-muted); }

.model-option-check { font-size: 14px; color: var(--accent-1); }

/* ── Chat Area ─────────────────────────────────── */
#chat-area {
  flex: 1;
  overflow: hidden;
  display: flex;
  flex-direction: column;
}

/* ── Welcome Screen ────────────────────────────── */
#welcome-screen {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 40px 20px;
  gap: 32px;
}

.welcome-hero {
  text-align: center;
  max-width: 520px;
}

.welcome-hero h1 {
  font-size: 36px;
  font-weight: 800;
  background: linear-gradient(135deg, var(--accent-1), var(--accent-2), var(--accent-3));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  letter-spacing: -1px;
  margin-bottom: 12px;
}

.welcome-hero p {
  font-size: 16px;
  color: var(--text-secondary);
  line-height: 1.7;
}

.provider-cards {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
}

.provider-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px 20px;
  text-align: center;
  min-width: 120px;
  transition: var(--transition);
}

.provider-card:hover {
  border-color: var(--accent-1);
  transform: translateY(-2px);
  box-shadow: var(--shadow-glow);
}

.provider-card-icon { font-size: 26px; margin-bottom: 6px; }
.provider-card-name { font-size: 13px; font-weight: 600; }
.provider-card-count { font-size: 11px; color: var(--text-muted); }

/* ── Messages Grid ─────────────────────────────── */
#messages-wrapper {
  flex: 1;
  overflow-y: auto;
  padding: 20px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.message-group { display: flex; flex-direction: column; gap: 12px; }

/* User message */
.user-message-row {
  display: flex;
  justify-content: flex-end;
}

.user-message-bubble {
  background: linear-gradient(135deg, var(--accent-1), var(--accent-2));
  color: white;
  padding: 12px 16px;
  border-radius: 16px 16px 4px 16px;
  max-width: 600px;
  font-size: 14px;
  line-height: 1.6;
  white-space: pre-wrap;
  word-break: break-word;
}

/* AI responses grid */
.ai-responses-grid {
  display: grid;
  gap: 14px;
}

.ai-responses-grid.cols-1 { grid-template-columns: 1fr; }
.ai-responses-grid.cols-2 { grid-template-columns: repeat(2, 1fr); }
.ai-responses-grid.cols-3 { grid-template-columns: repeat(3, 1fr); }
.ai-responses-grid.cols-4 { grid-template-columns: repeat(2, 1fr); }

/* AI Response Card */
.ai-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
  transition: var(--transition);
}

.ai-card:hover { border-color: rgba(99, 102, 241, 0.3); }

.ai-card-header {
  padding: 10px 14px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 8px;
}

.provider-dot { width: 8px; height: 8px; border-radius: 50%; flex-shrink: 0; }
.dot-openai { background: var(--openai); }
.dot-anthropic { background: var(--anthropic); }
.dot-google { background: var(--google); }
.dot-mistral { background: var(--mistral); }

.ai-card-model { font-size: 12px; font-weight: 600; flex: 1; }

.ai-card-meta {
  display: flex;
  gap: 8px;
  align-items: center;
}

.meta-badge {
  font-size: 10px;
  padding: 2px 7px;
  border-radius: 99px;
  background: var(--bg-input);
  color: var(--text-muted);
  font-weight: 500;
}

.meta-badge.time { color: var(--accent-3); }
.meta-badge.tokens { color: var(--accent-4); }

.ai-card-body {
  padding: 14px;
  font-size: 14px;
  line-height: 1.7;
  color: var(--text-primary);
  white-space: pre-wrap;
  word-break: break-word;
  overflow-wrap: break-word;
  max-height: 500px;
  overflow-y: auto;
}

.ai-card-body.error { color: #f87171; font-size: 13px; }

/* Code blocks */
.ai-card-body pre {
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px;
  overflow-x: auto;
  margin: 10px 0;
}

.ai-card-body code { font-family: 'JetBrains Mono', monospace; font-size: 13px; }

/* Loading skeleton */
.skeleton-line {
  background: linear-gradient(90deg, var(--bg-input) 25%, var(--bg-hover) 50%, var(--bg-input) 75%);
  background-size: 200% 100%;
  animation: skeleton-shimmer 1.5s infinite;
  border-radius: 4px;
  height: 14px;
  margin-bottom: 8px;
}

.skeleton-line:last-child { width: 60%; }
.skeleton-line:nth-child(2) { width: 85%; }

@keyframes skeleton-shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

.typing-indicator {
  display: flex;
  gap: 4px;
  align-items: center;
  padding: 8px 0;
}

.typing-dot {
  width: 6px; height: 6px;
  background: var(--accent-1);
  border-radius: 50%;
  animation: typing-bounce 1.2s infinite;
}

.typing-dot:nth-child(2) { animation-delay: 0.2s; }
.typing-dot:nth-child(3) { animation-delay: 0.4s; }

@keyframes typing-bounce {
  0%, 60%, 100% { transform: translateY(0); opacity: 0.5; }
  30% { transform: translateY(-6px); opacity: 1; }
}

/* ── Input Area ────────────────────────────────── */
#input-area {
  padding: 16px 20px;
  border-top: 1px solid var(--border);
  background: var(--bg-secondary);
  flex-shrink: 0;
}

.input-wrapper {
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  display: flex;
  align-items: flex-end;
  gap: 10px;
  padding: 10px 14px;
  transition: var(--transition);
  max-width: 1200px;
  margin: 0 auto;
}

.input-wrapper:focus-within {
  border-color: var(--accent-1);
  box-shadow: 0 0 0 3px rgba(99,102,241,0.1);
}

#message-input {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--text-primary);
  font-size: 14px;
  line-height: 1.5;
  resize: none;
  outline: none;
  max-height: 180px;
  overflow-y: auto;
  font-family: inherit;
}

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

.input-actions {
  display: flex;
  align-items: center;
  gap: 6px;
  padding-bottom: 2px;
}

.btn-send {
  width: 36px; height: 36px;
  background: linear-gradient(135deg, var(--accent-1), var(--accent-2));
  border: none;
  border-radius: 9px;
  color: white;
  cursor: pointer;
  font-size: 16px;
  display: flex; align-items: center; justify-content: center;
  transition: var(--transition);
  flex-shrink: 0;
}

.btn-send:hover { opacity: 0.85; transform: scale(1.05); }
.btn-send:disabled { opacity: 0.4; cursor: not-allowed; transform: none; }

.input-hint {
  text-align: center;
  font-size: 11px;
  color: var(--text-muted);
  margin-top: 8px;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
}

/* ── Settings Modal ────────────────────────────── */
.modal-overlay {
  position: fixed; inset: 0;
  background: rgba(0,0,0,0.7);
  backdrop-filter: blur(4px);
  z-index: 900;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.modal {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 540px;
  max-height: 90vh;
  overflow-y: auto;
  box-shadow: var(--shadow);
}

.modal-header {
  padding: 20px 24px 16px;
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.modal-title { font-size: 17px; font-weight: 700; }

.modal-body { padding: 20px 24px; }

.modal-footer {
  padding: 16px 24px;
  border-top: 1px solid var(--border);
  display: flex;
  justify-content: flex-end;
  gap: 10px;
}

.btn-secondary {
  padding: 9px 20px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: var(--transition);
}

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

.settings-section-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 12px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--border);
}

.api-key-row {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 10px;
}

.provider-label {
  display: flex;
  align-items: center;
  gap: 7px;
  min-width: 110px;
  font-size: 13px;
  font-weight: 500;
}

.provider-icon { font-size: 16px; }

.api-key-input-wrap {
  flex: 1;
  position: relative;
}

.api-key-input-wrap input {
  width: 100%;
  padding: 8px 36px 8px 12px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 13px;
  outline: none;
  transition: var(--transition);
  font-family: monospace;
}

.api-key-input-wrap input:focus { border-color: var(--accent-1); }

.btn-toggle-key {
  position: absolute;
  right: 8px; top: 50%;
  transform: translateY(-50%);
  background: none;
  border: none;
  color: var(--text-muted);
  cursor: pointer;
  font-size: 13px;
}

.key-status {
  width: 8px; height: 8px;
  border-radius: 50%;
  flex-shrink: 0;
}

.key-status.saved { background: var(--accent-4); }
.key-status.unsaved { background: var(--text-muted); }

.system-prompt-area {
  margin-top: 20px;
}

.system-prompt-area textarea {
  width: 100%;
  min-height: 100px;
  padding: 10px 12px;
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text-primary);
  font-size: 13px;
  resize: vertical;
  outline: none;
  font-family: inherit;
  transition: var(--transition);
}

.system-prompt-area textarea:focus { border-color: var(--accent-1); }

.slider-row {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 10px;
}

.slider-label { font-size: 13px; color: var(--text-secondary); min-width: 110px; }

input[type="range"] {
  flex: 1;
  accent-color: var(--accent-1);
}

.slider-value {
  font-size: 13px;
  font-weight: 600;
  color: var(--accent-1);
  min-width: 40px;
  text-align: right;
}

/* ── Toast ─────────────────────────────────────── */
#toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 9999;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.toast {
  padding: 12px 18px;
  border-radius: 10px;
  font-size: 13px;
  font-weight: 500;
  color: white;
  animation: toast-in 0.3s ease;
  box-shadow: var(--shadow);
  max-width: 300px;
}

.toast.success { background: var(--accent-4); }
.toast.error { background: #ef4444; }
.toast.info { background: var(--accent-1); }

@keyframes toast-in {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ── Utility ───────────────────────────────────── */
.hidden { display: none !important; }
.flex { display: flex; }
.items-center { align-items: center; }
.gap-8 { gap: 8px; }

.empty-state {
  text-align: center;
  padding: 40px 20px;
  color: var(--text-muted);
}

.empty-state-icon { font-size: 36px; margin-bottom: 10px; }
.empty-state-text { font-size: 14px; }

/* Provider dot colors inline style helpers */
.dot-color-openai { background-color: var(--openai) !important; }
.dot-color-anthropic { background-color: var(--anthropic) !important; }
.dot-color-google { background-color: var(--google) !important; }
.dot-color-mistral { background-color: var(--mistral) !important; }

/* ── Responsive ────────────────────────────────── */
@media (max-width: 900px) {
  #sidebar { width: 240px; }
  .ai-responses-grid.cols-3 { grid-template-columns: repeat(2, 1fr); }
  .ai-responses-grid.cols-4 { grid-template-columns: 1fr; }
  .model-dropdown { width: 380px; }
}

@media (max-width: 640px) {
  #sidebar { display: none; }
  .ai-responses-grid.cols-2,
  .ai-responses-grid.cols-3,
  .ai-responses-grid.cols-4 { grid-template-columns: 1fr; }
  .welcome-hero h1 { font-size: 26px; }
}