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

/* ===== COMPONENT RECIPES — THEME INVARIANT ===== */
:root {
  --bg: rgb(var(--color-bg));
  --purple-dark: rgb(var(--color-accent-deep));
  --purple-light: rgb(var(--color-text-primary));
  --purple-mid: rgb(var(--color-accent));
  --purple-soft: rgb(var(--color-accent-soft));
  --purple-glow: rgb(var(--color-shadow) / 0.35);
  --text-primary: rgb(var(--color-text-primary));
  --text-muted: rgb(var(--color-text-muted));
  --border-focus: rgb(var(--color-accent) / 0.60);
  --font: 'DM Sans', 'ui-sans-serif', system-ui, sans-serif;

  --sidebar-bg: rgb(var(--color-surface-elevated) / 0.82);
  --sidebar-border: rgb(var(--color-accent) / 0.30);
  --sidebar-shadow: 0 8px 40px rgb(var(--color-shadow) / 0.30), 0 2px 8px rgb(var(--color-neutral-shadow) / 0.40), inset 0 1px 0 rgb(var(--color-highlight) / 0.07);
  --sidebar-header-border: rgb(var(--color-accent) / 0.15);
  --history-item-hover: rgb(var(--color-text-secondary) / 0.06);
  --history-item-active: rgb(var(--color-accent) / 0.18);
  --history-title-color: rgb(var(--color-text-secondary) / 0.75);
  --history-action-color: rgb(var(--color-text-secondary) / 0.45);
  --history-empty-color: rgb(var(--color-text-secondary) / 0.40);
  --community-meta-color: rgb(var(--color-text-accent) / 0.50);
  --tab-inactive: rgb(var(--color-text-secondary) / 0.45);
  --tab-inactive-hover: rgb(var(--color-text-secondary) / 0.75);
  --tab-active-bg: rgb(var(--color-accent) / 0.18);
  --tab-active-border: rgb(var(--color-accent) / 0.35);

  --inputbox-bg: linear-gradient(135deg, rgb(var(--color-accent) / 0.12), rgb(var(--color-accent-deep) / 0.18)), rgb(var(--color-surface-raised) / 0.72);
  --inputbox-border: rgb(var(--color-highlight) / 0.12);
  --inputbox-shadow: 0 4px 32px rgb(var(--color-shadow) / 0.25), inset 0 1px 0 rgb(var(--color-highlight) / 0.06);
  --inputbox-shadow-focus: 0 4px 32px rgb(var(--color-shadow) / 0.35), inset 0 1px 0 rgb(var(--color-highlight) / 0.08);
  --textarea-color: rgb(var(--color-text-primary));
  --placeholder-color: rgb(var(--color-text-muted));

  --btn-bg: rgb(var(--color-surface-raised) / 0.60);
  --btn-border: rgb(var(--color-accent) / 0.30);
  --btn-color: rgb(var(--color-text-secondary) / 0.80);
  --btn-hover-bg: rgb(var(--color-accent) / 0.25);
  --btn-hover-border: rgb(var(--color-accent) / 0.80);

  --modelBtn-color: rgb(var(--color-text-secondary) / 0.75);
  --model-dropdown-bg: rgb(var(--color-surface-elevated) / 0.95);
  --model-item-color: rgb(var(--color-text-secondary) / 0.75);
  --model-empty-color: rgb(var(--color-text-secondary) / 0.40);

  --user-bubble-bg: linear-gradient(135deg, rgb(var(--color-accent) / 0.15), rgb(var(--color-accent-deep) / 0.22)), rgb(var(--color-surface-raised) / 0.36);
  --user-bubble-border: rgb(var(--color-accent) / 0.28);
  --user-bubble-shadow: 0 2px 16px rgb(var(--color-shadow) / 0.20), inset 0 1px 0 rgb(var(--color-highlight) / 0.07);
  --user-bubble-text: rgb(var(--color-text-primary));
  --ai-bubble-bg: rgb(var(--color-accent) / 0.08);
  --ai-bubble-border: rgb(var(--color-accent) / 0.18);
  --ai-bubble-shadow: 0 2px 12px rgb(var(--color-shadow) / 0.10), inset 0 1px 0 rgb(var(--color-highlight) / 0.04);
  --ai-bubble-text: rgb(var(--color-text-primary));
  --feedback-btn-color: rgb(var(--color-text-secondary) / 0.60);

  --ai-avatar-text: rgb(var(--color-on-accent));
  --system-bubble-bg: rgb(var(--color-danger) / 0.10);
  --system-bubble-border: rgb(var(--color-danger) / 0.20);
  --system-bubble-text: rgb(var(--color-danger-text));
  --danger-action-color: rgb(var(--color-danger-text));

  --shared-action-color: rgb(var(--color-accent));
  --shared-action-border: rgb(var(--color-accent) / 0.70);
  --shared-action-bg: rgb(var(--color-accent) / 0.15);

  --send-btn-bg: linear-gradient(135deg, rgb(var(--color-accent-deep) / 0.92), rgb(var(--color-accent) / 0.92));
  --send-btn-shadow: 0 2px 12px rgb(var(--color-shadow) / 0.40);
  --send-btn-color: rgb(var(--color-on-accent));

  --scrollbar-thumb: rgb(var(--color-scrollbar));
  --chat-scrollbar-thumb: rgb(var(--color-accent) / 0.30);

  --readonly-bg: rgb(var(--color-accent) / 0.10);
  --readonly-border: rgb(var(--color-accent) / 0.20);
  --readonly-color: rgb(var(--color-text-accent) / 0.85);

  --model-label-color: rgb(var(--color-text-accent) / 0.55);
  --powered-color: rgb(var(--color-text-secondary) / 0.50);
  --brand-gradient: linear-gradient(135deg, rgb(var(--color-text-primary)) 30%, rgb(var(--color-accent)) 100%);
  --brand-glow: drop-shadow(0 0 40px rgb(var(--color-accent) / 0.55));

  --home-btn-color: rgb(var(--color-text-secondary) / 0.35);
  --home-btn-hover-color: rgb(var(--color-text-secondary) / 0.80);
  --home-btn-hover-bg: rgb(var(--color-accent) / 0.15);
}
html, body {
  height: 100%;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text-primary);
  overflow: hidden;
  transition: background 0.3s ease, color 0.3s ease;
}

#bg-canvas {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
  pointer-events: none;
}

#main {
  position: fixed;
  inset: 0;
  z-index: 1;
  display: flex;
  flex-direction: column;
  background: transparent;
  transition: padding-left 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}
#main.sidebar-open { padding-left: 260px; }

/* ===== READ-ONLY BANNER ===== */
#readonly-banner {
  position: relative;
  z-index: 5;
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 8px 20px;
  background: var(--readonly-bg);
  border-bottom: 1px solid var(--readonly-border);
  font-size: 12.5px;
  color: var(--readonly-color);
}
#readonly-banner b { color: var(--purple-light); font-weight: 600; }

/* ===== CHAT ===== */
#chat {
  flex: 1;
  overflow-y: auto;
  padding: 32px 0;
  display: flex;
  flex-direction: column;
  scroll-behavior: smooth;
  opacity: 0;
  transition: opacity 0.3s ease;
}
#chat.visible { opacity: 1; }
#chat::-webkit-scrollbar { width: 5px; }
#chat::-webkit-scrollbar-thumb { background: var(--scrollbar-thumb); border-radius: 5px; }

.message-row {
  display: flex;
  max-width: 760px;
  width: 100%;
  margin: 0 auto;
  padding: 0px 24px 12px 24px;
  animation: slideUp 0.3s ease;
}
.message-row.user   { justify-content: flex-end; }
.message-row.ai     { justify-content: flex-start; gap: 12px; }
.message-row.system { justify-content: center; }

.ai-msg-body {
  display: flex;
  flex-direction: column;
  gap: 4px;
  max-width: 72%;
  min-width: 0;
}

.feedback-row {
  display: flex;
  gap: 4px;
  opacity: 0.5;
  transition: opacity 0.2s ease;
}
.message-row.ai:hover .feedback-row,
.feedback-row:focus-within { opacity: 1; }

.feedback-btn {
  width: 34px; height: 34px;
  border-radius: 8px;
  background: transparent;
  border: none;
  color: var(--feedback-btn-color);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color 0.15s, transform 0.1s;
}
.feedback-btn:hover { color: var(--purple-mid); }
.feedback-btn:active { transform: scale(0.9); }
.feedback-btn.liked,
.feedback-btn.disliked { color: var(--purple-mid); }

.ai-avatar {
  width: 28px; height: 28px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--purple-dark), var(--purple-mid));
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  align-self: flex-start;
  margin-top: 2px;
  font-size: 10px;
  font-weight: 700;
  color: var(--ai-avatar-text);
  letter-spacing: 0.03em;
}

.bubble { font-size: 15px; line-height: 1.7; }

.user .bubble {
  background: var(--user-bubble-bg);
  color: var(--user-bubble-text);
  border-radius: 18px 18px 4px 18px;
  padding: 11px 16px;
  border: 1px solid var(--user-bubble-border);
  box-shadow: var(--user-bubble-shadow);
  max-width: 80%;
  word-break: break-word;
}
.ai .bubble {
  background: var(--ai-bubble-bg);
  color: var(--ai-bubble-text);
  border: 1px solid var(--ai-bubble-border);
  border-radius: 3px 14px 14px 14px;
  padding: 10px 15px;
  text-align: justify;
  white-space: pre-wrap;
  word-break: break-word;
  box-shadow: var(--ai-bubble-shadow);
}
.system .bubble {
  background: var(--system-bubble-bg);
  color: var(--system-bubble-text);
  border-radius: 10px;
  font-size: 13px;
  border: 1px solid var(--system-bubble-border);
  padding: 8px 14px;
}

.typing-indicator { display: flex; gap: 5px; padding: 8px 4px; align-items: center; }
.typing-indicator span {
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--purple-mid);
  animation: bounce 1.2s infinite;
}
.typing-indicator span:nth-child(2) { animation-delay: 0.2s; }
.typing-indicator span:nth-child(3) { animation-delay: 0.4s; }

/* ===== WELCOME OVERLAY ===== */
#welcome-overlay {
  position: absolute;
  inset: 0;
  z-index: 10;
  pointer-events: none;
  transition: opacity 0.3s ease, visibility 0.3s ease;
}
#welcome-overlay.hidden { opacity: 0; visibility: hidden; }
#welcome-anchor { display: none; }

#brand {
  font-size: 96px;
  font-weight: 700;
  font-family: 'Playfair Display', serif;
  letter-spacing: 0.18em;
  background: var(--brand-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  line-height: 1;
  filter: var(--brand-glow);
  transition: opacity 0.4s ease, transform 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}
#brand.exit { opacity: 0; transform: translateY(-60px); }

#powered {
  font-size: 13.5px;
  color: var(--powered-color);
  letter-spacing: 0.06em;
  font-style: italic;
  font-family: 'Cormorant Garamond', 'Georgia', serif;
  transition: opacity 0.25s ease;
}
#powered.exit { opacity: 0; }

/* ===== INPUT WRAPPER ===== */
#input-wrapper {
  position: fixed;
  left: 50%;
  top: 50%;
  transform: translateX(-50%) translateY(-50%);
  width: min(680px, 100vw);
  padding: 0 24px;
  box-sizing: border-box;
  z-index: 20;
  pointer-events: auto;
  animation: fadeIn 0.7s ease 0.1s both;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 32px;
}
#input-wrapper.chat-pos {
  top: auto !important;
  bottom: 20px;
  left: auto;
  right: auto;
  transform: none;
  width: auto;
  max-width: none;
  display: block;
  padding: 0 24px;
  transition: top 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}
#input-wrapper .inputBox { width: 100%; }

#welcome-content {
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  animation: fadeIn 0.6s ease;
  transition: margin-left 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== INPUTBOX ===== */
.inputBox {
  display: flex;
  align-items: center;
  gap: 8px;
  background: var(--inputbox-bg);
  border-radius: 28px;
  padding: 8px 10px;
  border: 1px solid var(--inputbox-border);
  transition: border-color 0.2s, box-shadow 0.2s, background 0.3s;
  box-shadow: var(--inputbox-shadow);
}
.inputBox:focus-within {
  border-color: var(--border-focus);
  box-shadow: var(--inputbox-shadow-focus);
}

textarea {
  flex: 1;
  background: transparent;
  border: none;
  outline: none;
  color: var(--textarea-color);
  font-size: 15px;
  font-family: var(--font);
  line-height: 1.6;
  resize: none;
  max-height: 200px;
  overflow-y: auto;
  padding: 0 0 0 10px;
}
textarea::placeholder { color: var(--placeholder-color); }
textarea:disabled { opacity: 0.4; cursor: not-allowed; }

/* ===== SHARE TOGGLE BUTTON (in inputbox) ===== */
.input-action-btn {
  flex-shrink: 0;
  width: 34px; height: 34px;
  border-radius: 50%;
  background: var(--btn-bg);
  border: 1px solid var(--btn-border);
  color: var(--modelBtn-color);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color 0.15s, background 0.15s, border-color 0.15s;
}
.input-action-btn:hover {
  color: var(--purple-light);
  background: var(--btn-hover-bg);
  border-color: var(--btn-hover-border);
}
.input-action-btn.shared {
  color: var(--shared-action-color);
  border-color: var(--shared-action-border);
  background: var(--shared-action-bg);
}

#sendBtn {
  width: 34px; height: 34px;
  border-radius: 50%;
  background: var(--send-btn-bg);
  border: none;
  box-shadow: var(--send-btn-shadow);
  color: var(--send-btn-color);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: opacity 0.15s, transform 0.1s;
}
#sendBtn:hover { opacity: 0.85; }
#sendBtn:active { transform: scale(0.92); }
#sendBtn:disabled { opacity: 0.3; cursor: not-allowed; }

/* ===== ANIMATIONS ===== */
@keyframes fadeIn  { from { opacity: 0; }                          to { opacity: 1; } }
@keyframes slideUp { from { opacity: 0; transform: translateY(12px); } to { opacity: 1; transform: translateY(0); } }
@keyframes bounce  {
  0%, 60%, 100% { transform: translateY(0); }
  30%           { transform: translateY(-6px); }
}

@media (max-width: 640px) {
  #brand { font-size: 48px; }
  .bubble { max-width: 92%; }
}

/* ===== SIDEBAR ===== */
#sidebar {
  position: fixed;
  top: 12px; left: 12px;
  width: 236px;
  height: calc(100vh - 24px);
  z-index: 50;
  display: flex;
  flex-direction: column;
  background: var(--sidebar-bg);
  border: 1px solid var(--sidebar-border);
  border-radius: 20px;
  box-shadow: var(--sidebar-shadow);
  transform-origin: top left;
  transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.3s ease;
  overflow: hidden;
}
#sidebar.closed { transform: scale(0); opacity: 0; pointer-events: none; }

#sidebar-header {
  padding: 12px;
  border-bottom: 1px solid var(--sidebar-header-border);
  display: flex;
  align-items: center;
  gap: 8px;
}

#sidebar-title {
  color: var(--purple-light);
  font-family: var(--font);
  font-size: 13.5px;
  font-weight: 500;
}

.chat-loading {
  margin: auto;
  padding: 16px 24px;
  color: var(--history-empty-color);
  font: 500 13px var(--font);
  text-align: center;
}

#home-btn {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  border-radius: 7px;
  flex-shrink: 0;
  color: var(--home-btn-color);
  text-decoration: none;
  transition: color 0.2s, background 0.2s;
  margin-left: auto;
  border: 0;
  background: transparent;
  cursor: pointer;
}
#home-btn:hover {
  color: var(--home-btn-hover-color);
  background: var(--home-btn-hover-bg);
}

#new-chat-btn {
  display: flex;
  align-items: center;
  gap: 3px;
  width: 166px;
  padding: 9px 12px;
  background: var(--btn-bg);
  border: 1px solid var(--btn-border);
  border-radius: 28px;
  color: var(--purple-light);
  font-family: var(--font);
  font-size: 13.5px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s;
}
#new-chat-btn:hover { background: var(--btn-hover-bg); border-color: var(--btn-hover-border); }

/* ===== SIDEBAR TABS ===== */
#sidebar-tabs {
  display: flex;
  gap: 4px;
  padding: 10px 10px 2px;
}

.sidebar-tab {
  flex: 1;
  padding: 7px 0;
  border-radius: 10px;
  border: 1px solid transparent;
  background: transparent;
  color: var(--tab-inactive);
  font-family: var(--font);
  font-size: 12.5px;
  font-weight: 500;
  cursor: pointer;
  transition: color 0.15s, background 0.15s, border-color 0.15s;
  letter-spacing: 0.02em;
}
.sidebar-tab:hover { color: var(--tab-inactive-hover); }
.sidebar-tab.active {
  background: var(--tab-active-bg);
  border-color: var(--tab-active-border);
  color: var(--purple-light);
}

/* ===== HISTORY LIST ===== */
#history-list {
  flex: 1;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 8px 10px 10px;
}
#history-list::-webkit-scrollbar { width: 3px; }
#history-list::-webkit-scrollbar-thumb { background: var(--chat-scrollbar-thumb); border-radius: 3px; }

.history-empty {
  font-size: 12px;
  color: var(--history-empty-color);
  text-align: center;
  padding: 24px 8px;
  line-height: 1.5;
}

.history-folder-btn {
  align-self: center;
  padding: 8px 12px;
  border: 1px solid var(--btn-border);
  border-radius: 16px;
  background: var(--btn-bg);
  color: var(--btn-color);
  font: 500 12px var(--font);
  cursor: pointer;
  transition: color 0.15s, background 0.15s, border-color 0.15s;
}
.history-folder-btn:hover {
  color: var(--purple-light);
  background: var(--btn-hover-bg);
  border-color: var(--btn-hover-border);
}
.history-folder-btn-subtle {
  margin-top: 8px;
  background: transparent;
  border-color: transparent;
  opacity: 0.7;
}

.history-item {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 8px 10px;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.15s;
  width: 100%;
  border: 0;
  background: transparent;
  font-family: var(--font);
  text-align: left;
}
.history-item:hover  { background: var(--history-item-hover); }
.history-item.active { background: var(--history-item-active); }

.history-title {
  flex: 1;
  font-size: 13px;
  color: var(--history-title-color);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.history-item.active .history-title { color: var(--purple-light); }

/* action buttons inside history item */
.history-action {
  flex-shrink: 0;
  background: none;
  border: none;
  color: var(--history-action-color);
  cursor: pointer;
  padding: 3px;
  border-radius: 4px;
  display: flex;
  opacity: 0;
  transition: opacity 0.15s, color 0.15s;
}
.history-item:hover .history-action { opacity: 1; }
.history-action:hover { color: var(--purple-light); }
.history-delete:hover { color: var(--danger-action-color); }
.share-btn.shared { color: var(--purple-mid); opacity: 1; }

/* ===== COMMUNITY ITEMS ===== */
.community-item { flex-direction: column; align-items: flex-start; gap: 2px; }
.community-meta {
  font-size: 10.5px;
  color: var(--community-meta-color);
  letter-spacing: 0.04em;
  font-weight: 600;
}
.community-item .history-title { font-size: 12.5px; }

/* ===== SIDEBAR BUTTONS ===== */
#sidebar-toggle {
  flex-shrink: 0;
  background: var(--btn-bg);
  border: 1px solid var(--btn-border);
  border-radius: 50%;
  color: var(--btn-color);
  cursor: pointer;
  width: 38px; height: 38px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: color 0.15s, background 0.15s, border-color 0.15s;
}
#sidebar-toggle:hover { color: var(--purple-light); background: var(--btn-hover-bg); border-color: var(--btn-hover-border); }

#sidebar-open-btn {
  position: fixed;
  top: 24px; left: 24px;
  z-index: 60;
  background: var(--btn-bg);
  border: 1px solid var(--btn-border);
  border-radius: 50%;
  color: var(--btn-color);
  cursor: pointer;
  width: 38px; height: 38px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: opacity 0.2s ease, color 0.15s, background 0.15s, border-color 0.15s;
}
#sidebar-open-btn:hover { color: var(--purple-light); background: var(--btn-hover-bg); border-color: var(--btn-hover-border); }
#sidebar-open-btn.hidden { opacity: 0; pointer-events: none; }

/* ===== MODEL SELECTOR ===== */
#model-selector-wrap { position: relative; flex-shrink: 0; }

#modelBtn {
  display: flex;
  align-items: center;
  gap: 5px;
  padding: 8px 10px;
  background: var(--btn-bg);
  border: 1px solid var(--btn-border);
  border-radius: 20px;
  color: var(--modelBtn-color);
  font-family: var(--font);
  font-size: 12.5px;
  font-weight: 500;
  cursor: pointer;
  white-space: nowrap;
  transition: background 0.15s, border-color 0.15s, color 0.15s;
  max-width: 130px;
}
#modelBtn:hover { color: var(--purple-light); background: var(--btn-hover-bg); border-color: var(--btn-hover-border); }
#modelBtn span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; max-width: 80px; }
#modelChevron { flex-shrink: 0; transition: transform 0.2s ease; opacity: 0.7; }
#modelBtn.loading { opacity: 0.5; pointer-events: none; cursor: wait; }

.model-dropdown {
  position: absolute;
  bottom: calc(100% + 8px);
  left: 0;
  min-width: 200px;
  background: var(--model-dropdown-bg);
  border: 1px solid var(--sidebar-border);
  border-radius: 14px;
  box-shadow: var(--sidebar-shadow);
  overflow: hidden;
  z-index: 100;
  animation: dropUp 0.18s cubic-bezier(0.34, 1.4, 0.64, 1);
}
.model-dropdown.hidden { display: none; }

@keyframes dropUp {
  from { opacity: 0; transform: translateY(8px) scale(0.97); }
  to   { opacity: 1; transform: translateY(0) scale(1); }
}

#model-list {
  padding: 6px;
  display: flex;
  flex-direction: column;
  gap: 2px;
  max-height: 220px;
  overflow-y: auto;
}
#model-list::-webkit-scrollbar { width: 3px; }
#model-list::-webkit-scrollbar-thumb { background: var(--chat-scrollbar-thumb); border-radius: 3px; }

.model-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 10px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 13px;
  color: var(--model-item-color);
  transition: background 0.12s, color 0.12s;
  border: none;
  background: transparent;
  font-family: var(--font);
  width: 100%;
  text-align: left;
}
.model-item:hover  { background: var(--history-item-hover); color: var(--purple-light); }
.model-item.active { background: var(--history-item-active); color: var(--purple-light); }
.model-item svg:first-child { flex-shrink: 0; opacity: 0.6; }
.model-item.active svg:first-child { opacity: 1; }
.model-item span { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.model-check { flex-shrink: 0; opacity: 0; color: var(--purple-mid); }
.model-item.active .model-check { opacity: 1; }
.model-empty { padding: 12px 14px; font-size: 12px; color: var(--model-empty-color); text-align: center; }

/* ===== MODEL LABEL trên tin nhắn AI ===== */
.model-label-row {
  max-width: 760px;
  width: 100%;
  margin: 0 auto;
  padding: 10px 24px 5px;
  padding-left: calc(24px + 28px + 12px);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.04em;
  color: var(--model-label-color);
  user-select: none;
  line-height: 1;
}

/* ===== STATIC DEMO NOTICE ===== */
.demo-notice {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: grid;
  place-items: center;
  padding: 24px;
  transition: opacity 0.2s ease, visibility 0.2s ease;
}
.demo-notice.is-hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}
.demo-notice-backdrop {
  position: absolute;
  inset: 0;
  background: rgb(var(--color-bg) / 0.72);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}
.demo-notice-card {
  position: relative;
  width: min(560px, 100%);
  max-height: calc(100dvh - 48px);
  overflow-y: auto;
  padding: 32px;
  border: 1px solid rgb(var(--color-accent) / 0.34);
  border-radius: 24px;
  background:
    linear-gradient(145deg, rgb(var(--color-accent) / 0.13), rgb(var(--color-accent-deep) / 0.17)),
    rgb(var(--color-surface-elevated) / 0.94);
  box-shadow: 0 24px 80px rgb(var(--color-shadow) / 0.42),
    inset 0 1px 0 rgb(var(--color-highlight) / 0.08);
  animation: demoNoticeIn 0.32s cubic-bezier(0.34, 1.3, 0.64, 1);
  scrollbar-width: thin;
  scrollbar-color: rgb(var(--color-accent) / 0.35) transparent;
}
.demo-notice-close {
  position: absolute;
  top: 16px;
  right: 16px;
  width: 34px;
  height: 34px;
  display: grid;
  place-items: center;
  border: 1px solid var(--btn-border);
  border-radius: 50%;
  background: var(--btn-bg);
  color: var(--btn-color);
  cursor: pointer;
  transition: color 0.15s, background 0.15s, border-color 0.15s;
}
.demo-notice-close:hover {
  color: var(--purple-light);
  background: var(--btn-hover-bg);
  border-color: var(--btn-hover-border);
}
.demo-notice-icon {
  width: 46px;
  height: 46px;
  display: grid;
  place-items: center;
  margin-bottom: 22px;
  border: 1px solid rgb(var(--color-accent) / 0.46);
  border-radius: 14px;
  background: linear-gradient(135deg, rgb(var(--color-accent-deep) / 0.85), rgb(var(--color-accent) / 0.78));
  box-shadow: 0 8px 24px rgb(var(--color-shadow) / 0.3);
  color: rgb(var(--color-on-accent));
  font: 700 12px var(--font);
  letter-spacing: 0.08em;
}
.demo-notice-eyebrow {
  margin-bottom: 8px;
  color: rgb(var(--color-text-accent) / 0.78);
  font: 600 11px var(--font);
  letter-spacing: 0.12em;
  text-transform: uppercase;
}
.demo-notice h2 {
  padding-right: 32px;
  color: var(--text-primary);
  font: 700 clamp(22px, 4vw, 28px)/1.25 var(--font);
  letter-spacing: -0.025em;
}
.demo-notice-description {
  display: grid;
  gap: 13px;
  margin-top: 18px;
  color: rgb(var(--color-text-secondary) / 0.76);
  font: 400 14px/1.72 var(--font);
}
.demo-notice-description strong {
  color: var(--text-primary);
  font-weight: 600;
}
.demo-notice-links {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 24px;
}
.demo-notice-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 7px;
  padding: 10px 14px;
  border: 1px solid var(--btn-border);
  border-radius: 100px;
  background: var(--btn-bg);
  color: rgb(var(--color-text-secondary) / 0.86);
  font: 600 12.5px var(--font);
  text-decoration: none;
  transition: color 0.15s, background 0.15s, border-color 0.15s, transform 0.15s;
}
.demo-notice-link:hover {
  color: var(--purple-light);
  background: var(--btn-hover-bg);
  border-color: var(--btn-hover-border);
  transform: translateY(-1px);
}
.demo-notice-link-primary {
  border-color: rgb(var(--color-accent) / 0.64);
  background: rgb(var(--color-accent) / 0.2);
  color: var(--text-primary);
}
.demo-notice-confirm {
  width: 100%;
  margin-top: 22px;
  padding: 12px 18px;
  border: 0;
  border-radius: 100px;
  background: var(--send-btn-bg);
  box-shadow: var(--send-btn-shadow);
  color: var(--send-btn-color);
  font: 600 13.5px var(--font);
  cursor: pointer;
  transition: opacity 0.15s, transform 0.15s;
}
.demo-notice-confirm:hover { opacity: 0.88; }
.demo-notice-confirm:active { transform: scale(0.985); }

@keyframes demoNoticeIn {
  from { opacity: 0; transform: translateY(16px) scale(0.97); }
  to { opacity: 1; transform: translateY(0) scale(1); }
}

@media (max-width: 560px) {
  .demo-notice { align-items: end; padding: 12px; }
  .demo-notice-card {
    width: 100%;
    max-height: calc(100dvh - 24px);
    padding: 26px 20px 20px;
    border-radius: 22px;
  }
  .demo-notice-close { top: 13px; right: 13px; }
  .demo-notice-icon { width: 42px; height: 42px; margin-bottom: 18px; }
  .demo-notice h2 { padding-right: 38px; }
  .demo-notice-description { font-size: 13.5px; line-height: 1.65; }
  .demo-notice-links { display: grid; grid-template-columns: 1fr 1fr; }
  .demo-notice-link { min-width: 0; padding-inline: 10px; }
}
@media (max-width: 390px) {
  .demo-notice-links { grid-template-columns: 1fr; }
}
@media (prefers-reduced-motion: reduce) {
  .demo-notice-card { animation: none; }
  .demo-notice { transition: none; }
}

/* ===== MOBILE CHAT REFINEMENT ===== */
@media (max-width: 640px) {
  #chat {
    padding: 20px 0 28px;
  }

  .message-row {
    padding: 0 14px 10px;
  }

  .message-row.ai {
    gap: 8px;
  }

  .ai-msg-body {
    max-width: calc(100% - 32px);
    gap: 2px;
  }

  .bubble {
    max-width: none;
    font-size: 13.5px;
    line-height: 1.55;
  }

  .user .bubble {
    max-width: 88%;
    padding: 9px 13px;
    border-radius: 16px 16px 4px 16px;
  }

  .ai .bubble {
    padding: 9px 12px;
    text-align: left;
    overflow-wrap: anywhere;
    word-break: normal;
    border-radius: 3px 12px 12px 12px;
  }

  .ai-avatar {
    width: 24px;
    height: 24px;
    margin-top: 1px;
    font-size: 8.5px;
  }

  .feedback-row {
    gap: 2px;
  }

  .feedback-btn {
    width: 30px;
    height: 30px;
  }

  .feedback-btn svg {
    width: 15px;
    height: 15px;
  }

  .model-label-row {
    padding: 8px 14px 4px 46px;
    font-size: 10px;
  }
}