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

.hidden {
  display: none !important;
}

:root {
  --bg: #f5f7fb;
  --surface: #ffffff;
  --primary: #4f6ef7;
  --primary-dark: #3a55d4;
  --bot-bubble: #ffffff;
  --user-bubble: #4f6ef7;
  --user-bubble-text: #ffffff;
  --text: #1a1a2e;
  --text-muted: #6b7280;
  --border: #e5e7eb;
  --correct: #16a34a;
  --wrong: #dc2626;
  --radius: 16px;
  --radius-sm: 8px;
}

[data-theme="dark"] {
  --bg: #0f1117;
  --surface: #1a1d27;
  --bot-bubble: #1e2130;
  --user-bubble: #3a55d4;
  --user-bubble-text: #ffffff;
  --text: #e2e8f0;
  --text-muted: #8892a4;
  --border: #2d3148;
  --correct: #22c55e;
  --wrong: #f87171;
}

html, body {
  height: 100%;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  font-size: 14px;
  background: var(--bg);
  color: var(--text);
}

#app {
  display: flex;
  flex-direction: column;
  height: 100vh;
  height: 100dvh;
  height: var(--real-vh, 100dvh); /* точна висота без браузерного chrome */
}

/* Header */
.header {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 12px 16px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.header-icon {
  font-size: 18px;
}

.header-title {
  font-weight: 600;
  font-size: 15px;
  color: var(--text);
}

.header-actions {
  display: none;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.header-actions.visible {
  display: flex;
}

.header-btn {
  padding: 4px 10px;
  border-radius: 12px;
  font-size: calc(var(--msg-font) - 1px);
  font-family: inherit;
  font-weight: 500;
  cursor: pointer;
  border: 1.5px solid var(--primary);
  background: var(--primary);
  color: #fff;
  transition: background 0.15s, opacity 0.15s;
  white-space: nowrap;
}

.header-btn:hover {
  background: var(--primary-dark);
  border-color: var(--primary-dark);
}

.header-btn--ghost {
  background: transparent;
  color: var(--primary);
}

.header-btn--ghost:hover {
  background: var(--primary);
  color: #fff;
}

.header-btn--weak {
  background: transparent;
  color: var(--wrong);
  border-color: var(--wrong);
}

.header-btn--weak:hover {
  background: var(--wrong);
  color: #fff;
}

.header-spacer {
  flex: 1;
}

.theme-toggle {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text-muted);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: background 0.15s, color 0.15s;
}

.theme-toggle:hover {
  color: var(--text);
  background: var(--border);
}

.theme-toggle:disabled {
  opacity: 0.35;
  cursor: not-allowed;
  position: relative;
  overflow: hidden;
}

.theme-toggle:disabled:hover {
  color: var(--text-muted);
  background: var(--bg);
}

/* Перекреслене коло поверх іконки */
.theme-toggle:disabled::after {
  content: '';
  position: absolute;
  inset: 3px;
  border-radius: 50%;
  border: 1.5px solid currentColor;
  background: linear-gradient(
    to top right,
    transparent calc(50% - 0.75px),
    currentColor calc(50% - 0.75px),
    currentColor calc(50% + 0.75px),
    transparent calc(50% + 0.75px)
  );
  opacity: 0.7;
  pointer-events: none;
}

/* Subheader (exam actions + stopwatch) */
.subheader {
  display: none;
  align-items: center;
  padding: 7px 16px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
  gap: 8px;
}

.subheader.visible {
  display: flex;
}

.exam-btns {
  display: none;
  align-items: center;
  gap: 6px;
}

.exam-btns.visible {
  display: flex;
}

.stopwatch {
  margin-left: auto;
  font-size: var(--msg-font);
  font-weight: 600;
  font-variant-numeric: tabular-nums;
  color: var(--text-muted);
  letter-spacing: 0.03em;
}

/* Exam progress bar */
.exam-progress {
  height: 3px;
  background: var(--border);
  flex-shrink: 0;
}

.exam-progress.hidden {
  display: none;
}

.exam-progress-fill {
  height: 100%;
  background: var(--primary);
  width: 0%;
  transition: width 0.4s ease;
}

/* Font size dropdown */
.font-size-dropdown {
  position: relative;
  margin-right: 4px;
}

.font-size-trigger {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--bg);
  color: var(--text-muted);
  font-family: inherit;
  font-weight: 600;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background 0.15s, color 0.15s;
}

.font-size-trigger:hover {
  background: var(--border);
  color: var(--text);
}

.font-size-menu {
  display: none;
  position: absolute;
  top: calc(100% + 6px);
  right: 0;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  box-shadow: 0 4px 12px rgba(0,0,0,0.12);
  z-index: 50;
  overflow: hidden;
  min-width: 110px;
}

.font-size-menu.open {
  display: block;
}

.font-size-option {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 8px 12px;
  border: none;
  background: none;
  color: var(--text);
  font-family: inherit;
  font-weight: 600;
  cursor: pointer;
  text-align: left;
  transition: background 0.12s;
}

.font-size-option span {
  font-size: 12px;
  font-weight: 400;
  color: var(--text-muted);
}

.font-size-option[data-size="small"]  { font-size: 11px; }
.font-size-option[data-size="medium"] { font-size: 14px; }
.font-size-option[data-size="large"]  { font-size: 17px; }

.font-size-option:hover {
  background: var(--border);
}

.font-size-option.active {
  color: var(--primary);
  background: color-mix(in srgb, var(--primary) 8%, transparent);
}

.font-size-option.active span {
  color: var(--primary);
}

/* Font size variable */
:root                { --msg-font: 13px; }
[data-font="medium"] { --msg-font: 15px; }
[data-font="large"]  { --msg-font: 17px; }

.messages,
.messages .bubble,
.messages .chat-btn,
.messages .system-notice,
.messages .explain-panel-content,
.messages .explain-chat-user,
.messages .explain-chat-bot,
.messages .explain-mini-input input,
.messages .explain-mini-input button,
.messages .dispute-result { font-size: var(--msg-font); }

.settings-dialog { font-size: var(--msg-font); }

.messages .action-btn,
.messages .skip-link,
.messages .dispute-input,
.messages .dispute-submit { font-size: calc(var(--msg-font) - 1px); }

.user-input { font-size: var(--msg-font); }

.input-wrap {
  background: var(--surface);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
  padding-bottom: env(safe-area-inset-bottom, 0px);
}

.input-hint {
  font-size: 10px;
  color: var(--text-muted);
  text-align: center;
  padding: 3px 12px 5px;
  opacity: 0.7;
}

/* Show sun in dark mode, moon in light mode */
.icon-moon { display: block; }
.icon-sun  { display: none;  }

[data-theme="dark"] .icon-moon { display: none;  }
[data-theme="dark"] .icon-sun  { display: block; }

/* Messages */
.messages {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
  padding: 16px 12px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  scroll-behavior: smooth;
}

/* Message bubbles */
.message {
  display: flex;
  flex-direction: column;
  max-width: 88%;
}

.message.bot {
  align-self: flex-start;
}

.message.user {
  align-self: flex-end;
  align-items: flex-end;
}

.bubble {
  padding: 10px 14px;
  border-radius: var(--radius);
  line-height: 1.5;
  word-break: break-word;
}

.message.bot .bubble {
  background: var(--bot-bubble);
  border: 1px solid var(--border);
  border-bottom-left-radius: 4px;
  box-shadow: 0 1px 2px rgba(0,0,0,0.05);
}

.message.user .bubble {
  background: var(--user-bubble);
  color: var(--user-bubble-text);
  border-bottom-right-radius: 4px;
}

/* Feedback bubbles */
.bubble.correct {
  border-left: 3px solid var(--correct);
}

.bubble.wrong {
  border-left: 3px solid var(--wrong);
}

.feedback-icon {
  font-size: 16px;
  margin-right: 4px;
}

/* Buttons in chat */
.btn-group {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 8px;
}

.chat-btn {
  padding: 6px 14px;
  border: 1.5px solid var(--primary);
  background: transparent;
  color: var(--primary);
  border-radius: 20px;
  font-size: 13px;
  cursor: pointer;
  transition: background 0.15s, color 0.15s;
  font-family: inherit;
}

.chat-btn:hover {
  background: var(--primary);
  color: white;
}

.chat-btn--selected {
  background: var(--primary);
  color: white;
  border-color: var(--primary);
}

.chat-btn--selected:disabled {
  opacity: 1;
}


/* Typing indicator */
.typing .bubble {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 12px 16px;
}

.dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--text-muted);
  animation: bounce 1.2s infinite ease-in-out;
}

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

@keyframes bounce {
  0%, 60%, 100% { transform: translateY(0); }
  30% { transform: translateY(-5px); }
}

/* Input area */
.input-area {
  display: flex;
  align-items: flex-end;
  gap: 8px;
  padding: 10px 12px 6px;
}

.user-input {
  flex: 1;
  padding: 9px 14px;
  border: 1.5px solid var(--border);
  border-radius: 18px;
  font-size: 14px;
  font-family: inherit;
  outline: none;
  background: var(--bg);
  color: var(--text);
  transition: border-color 0.15s;
  resize: none;
  overflow-y: hidden;
  scrollbar-width: thin;
  scrollbar-color: var(--border) transparent;
  line-height: 1.5;
  min-height: 38px;
  max-height: 120px; /* ~5 рядків */
  display: block;
}

.user-input:focus {
  border-color: var(--primary);
}

.user-input:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.user-input::-webkit-scrollbar {
  width: 4px;
}
.user-input::-webkit-scrollbar-track {
  background: transparent;
  margin: 10px 0;
}
.user-input::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 2px;
}

.send-btn {
  width: 38px;
  height: 38px;
  border-radius: 50%;
  border: none;
  background: var(--primary);
  color: white;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  transition: background 0.15s;
}

.send-btn:hover {
  background: var(--primary-dark);
}

.send-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* System notice */
.system-notice {
  align-self: center;
  font-size: 12px;
  color: #92400e;
  background: #fff8e1;
  border: 1px solid #f59e0b;
  border-radius: var(--radius-sm);
  padding: 8px 12px;
  text-align: center;
  max-width: 92%;
}

[data-theme="dark"] .system-notice {
  color: #fbbf24;
  background: #1c1708;
  border-color: #92400e;
}

/* Skip button */
.skip-link {
  display: block;
  text-align: right;
  margin-top: 6px;
  padding: 0;
  background: none;
  border: none;
  font-family: inherit;
  font-size: 12px;
  color: var(--text-muted);
  cursor: pointer;
  opacity: 0.7;
  transition: opacity 0.15s;
}
.skip-link:hover { opacity: 1; }
.skip-link:disabled { opacity: 0.3; cursor: default; }

/* Answer action buttons (Не згоден, Поясни детальніше) */
.answer-actions {
  display: flex;
  gap: 6px;
  margin-top: 8px;
  flex-wrap: wrap;
}

.action-btn {
  padding: 4px 12px;
  border-radius: 12px;
  font-size: 12px;
  font-family: inherit;
  cursor: pointer;
  border: 1.5px solid var(--border);
  background: transparent;
  color: var(--text-muted);
  transition: border-color 0.15s, color 0.15s, background 0.15s;
}
.action-btn:hover:not(:disabled) {
  border-color: var(--primary);
  color: var(--primary);
  background: color-mix(in srgb, var(--primary) 8%, transparent);
}
.action-btn:disabled {
  opacity: 0.35;
  cursor: not-allowed;
}

.action-btn--active {
  border-color: var(--primary);
  color: var(--primary);
  background: color-mix(in srgb, var(--primary) 10%, transparent);
  font-weight: 500;
}

.action-btn.action-btn--active:hover {
  background: var(--primary);
  color: #fff;
  border-color: var(--primary);
}

[data-theme="dark"] .action-btn--active {
  background: color-mix(in srgb, var(--primary) 15%, transparent);
}

/* Inline dispute form */
.dispute-form {
  display: flex;
  gap: 6px;
  margin-top: 10px;
}
.dispute-input {
  flex: 1;
  padding: 6px 10px;
  border: 1.5px solid var(--wrong);
  border-radius: 12px;
  font-size: 12px;
  font-family: inherit;
  background: var(--bg);
  color: var(--text);
  outline: none;
}
.dispute-submit {
  padding: 6px 12px;
  border: none;
  border-radius: 12px;
  background: var(--wrong);
  color: white;
  font-size: 12px;
  font-family: inherit;
  cursor: pointer;
}
.dispute-submit:disabled { opacity: 0.5; cursor: default; }

.dispute-loading {
  display: flex;
  align-items: center;
  gap: 4px;
  margin-top: 8px;
  padding: 4px 0;
}

.dispute-loading .dot {
  width: 6px;
  height: 6px;
}

.dispute-result {
  margin-top: 8px;
  padding-top: 8px;
  border-top: 1px solid var(--border);
  font-size: 13px;
  line-height: 1.5;
}

/* Explain panel */
.explain-panel {
  margin-top: 10px;
  padding-top: 10px;
  border-top: 2px solid var(--primary);
}
.explain-panel-title {
  font-size: 10px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--primary);
  margin-bottom: 8px;
}
.explain-panel-content {
  font-size: 13px;
  line-height: 1.6;
  color: var(--text);
  white-space: pre-wrap;
  background: #f0fdf4;
  border: 1px solid #bbf7d0;
  border-left: 3px solid var(--correct);
  border-radius: var(--radius);
  border-bottom-left-radius: 4px;
  padding: 10px 14px;
}

[data-theme="dark"] .explain-panel-content {
  background: #0d1f14;
  border-color: #166534;
  border-left-color: var(--correct);
}

/* Mini chat inside explain panel */
.explain-chat {
  margin-top: 10px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.explain-chat-user {
  align-self: flex-end;
  background: var(--user-bubble);
  color: var(--user-bubble-text);
  padding: 5px 10px;
  border-radius: 12px;
  border-bottom-right-radius: 3px;
  font-size: 12px;
  max-width: 90%;
}
.explain-chat-bot {
  align-self: flex-start;
  background: #f0fdf4;
  border: 1px solid #bbf7d0;
  color: var(--text);
  padding: 5px 10px;
  border-radius: 12px;
  border-bottom-left-radius: 3px;
  font-size: 12px;
  max-width: 90%;
  line-height: 1.5;
}

[data-theme="dark"] .explain-chat-bot {
  background: #0d1f14;
  border-color: #166534;
}

.explain-mini-input {
  display: flex;
  gap: 6px;
  margin-top: 8px;
}
.explain-mini-input input {
  flex: 1;
  padding: 6px 10px;
  border: 1.5px solid #bbf7d0;
  border-radius: 12px;
  font-size: 12px;
  font-family: inherit;
  background: var(--bg);
  color: var(--text);
  outline: none;
}
.explain-mini-input input:focus { border-color: var(--correct); }

[data-theme="dark"] .explain-mini-input input {
  border-color: #166534;
}
[data-theme="dark"] .explain-mini-input input:focus {
  border-color: var(--correct);
}

.explain-mini-input button {
  padding: 6px 12px;
  border: none;
  border-radius: 12px;
  background: var(--correct);
  color: white;
  font-size: 13px;
  font-family: inherit;
  cursor: pointer;
}
.explain-mini-input button:disabled { opacity: 0.5; cursor: default; }

/* Settings modal */
.settings-modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.45);
  z-index: 100;
  align-items: center;
  justify-content: center;
}

.settings-modal.visible {
  display: flex;
}

.settings-dialog {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  width: 90%;
  max-width: 460px;
  max-height: 90vh;
  overflow: hidden;
  box-shadow: 0 8px 32px rgba(0,0,0,0.18);
  display: flex;
  flex-direction: column;
}

.settings-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px 16px 10px;
  border-bottom: 1px solid var(--border);
}

.settings-title {
  font-weight: 600;
}

.settings-close {
  background: none;
  border: none;
  font-size: 20px;
  line-height: 1;
  cursor: pointer;
  color: var(--text-muted);
  padding: 0 4px;
}

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

.settings-form {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 16px;
  flex: 1;
  overflow-y: auto;
}

.settings-label {
  display: flex;
  flex-direction: column;
  gap: 5px;
  font-weight: 500;
  color: var(--text-muted);
}

.settings-label--row {
  flex-direction: row;
  align-items: center;
  gap: 8px;
  color: var(--text);
  font-weight: 400;
  cursor: pointer;
}

.settings-input {
  padding: 8px 12px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: inherit;
  font-family: inherit;
  background: var(--bg);
  color: var(--text);
  outline: none;
  transition: border-color 0.15s;
}

.settings-input:focus {
  border-color: var(--primary);
}

.settings-apikey-wrap {
  display: flex;
  gap: 6px;
}

.settings-apikey-wrap .settings-input {
  flex: 1;
  min-width: 0;
}

.settings-apikey-toggle {
  padding: 8px 10px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--bg);
  color: var(--text-muted);
  font-size: inherit;
  font-family: inherit;
  cursor: pointer;
  white-space: nowrap;
  transition: border-color 0.15s, color 0.15s;
}

.settings-apikey-toggle:hover {
  border-color: var(--primary);
  color: var(--primary);
}

.settings-nano-wrap {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.settings-nano-hint {
  font-size: 11px;
  color: var(--wrong);
  padding-left: 22px;
}

.settings-nano-hint.hidden {
  display: none;
}

.settings-pool-section {
  border-top: 1px solid var(--border);
  padding-top: 10px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.settings-pool-title {
  font-size: 0.85em;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

.settings-pool-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin: 1px 0;
}

.settings-pool-text {
  flex: 1;
  font-size: 0.9em;
}

.settings-pool-empty {
  color: var(--text-muted);
}

.settings-pool-reset {
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.8em;
  color: var(--text-muted);
  cursor: pointer;
  padding: 2px 8px;
  font-family: inherit;
  transition: color 0.15s, border-color 0.15s;
  white-space: nowrap;
}

.settings-pool-reset:hover:not(:disabled) {
  color: var(--wrong);
  border-color: var(--wrong);
}

.settings-pool-reset:disabled {
  opacity: 0.4;
  cursor: default;
}

.settings-appearance {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
  margin-bottom: 4px;
}

.settings-appearance-row {
  display: flex;
  align-items: center;
  gap: 10px;
}

.settings-appearance-label {
  font-size: 0.85em;
  color: var(--text-muted);
  width: 3.5em;
}

.settings-seg {
  display: flex;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.settings-seg-btn {
  background: none;
  border: none;
  border-right: 1px solid var(--border);
  font-family: inherit;
  font-size: 0.85em;
  padding: 4px 12px;
  cursor: pointer;
  color: var(--text);
  transition: background 0.15s, color 0.15s;
  white-space: nowrap;
}

.settings-seg-btn:last-child { border-right: none; }

.settings-seg-btn--active {
  background: var(--primary);
  color: #fff;
}

.settings-seg-btn:not(.settings-seg-btn--active):hover {
  background: var(--border);
}

.settings-seg-btn--font-s,
.settings-seg-btn--font-m,
.settings-seg-btn--font-l {
  line-height: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  height: 30px;
}

.settings-seg-btn--font-s { font-size: 0.72em; }
.settings-seg-btn--font-m { font-size: 0.95em; }
.settings-seg-btn--font-l { font-size: 1.22em; }

.settings-footer {
  flex-shrink: 0;
  padding: 12px 16px 10px;
  border-top: 1px solid var(--border);
  background: var(--surface);
  display: flex;
  flex-direction: column;
  gap: 0;
}

.settings-save {
  padding: 10px;
  border: none;
  border-radius: var(--radius-sm);
  background: var(--primary);
  color: #fff;
  font-size: inherit;
  font-family: inherit;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.15s;
}

.settings-save:hover {
  background: var(--primary-dark);
}

.settings-version {
  text-align: center;
  font-size: 0.75em;
  color: var(--text-muted);
  padding-top: 6px;
}

/* API key label with info button */
.settings-label-row {
  display: flex;
  align-items: center;
  gap: 4px;
}

.settings-info-btn {
  background: none;
  border: none;
  padding: 0;
  cursor: pointer;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  flex-shrink: 0;
  transition: color 0.15s;
}

.settings-info-btn:hover {
  color: var(--primary);
}

/* API key info popup */
.apikey-popup {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.45);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 300;
}

.apikey-popup.hidden {
  display: none;
}

.apikey-popup-dialog {
  background: var(--surface);
  border-radius: var(--radius);
  padding: 20px;
  max-width: 320px;
  width: calc(100% - 32px);
  position: relative;
  box-shadow: 0 8px 24px rgba(0,0,0,0.18);
  font-size: var(--msg-font);
}

.apikey-popup-close {
  position: absolute;
  top: 10px;
  right: 12px;
  background: none;
  border: none;
  font-size: 1.4em;
  cursor: pointer;
  color: var(--text-muted);
  line-height: 1;
}

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

.apikey-popup-title {
  font-weight: 600;
  font-size: 1em;
  margin-bottom: 12px;
  padding-right: 20px;
}

.apikey-popup-body p,
.apikey-popup-body ol {
  margin: 0 0 10px;
  font-size: 0.88em;
  line-height: 1.5;
  color: var(--text);
}

.apikey-popup-body ol {
  padding-left: 18px;
}

.apikey-popup-body ol li {
  margin-bottom: 4px;
}

.apikey-popup-body a {
  color: var(--primary);
  text-decoration: underline;
}

.apikey-popup-tip {
  font-size: 0.82em;
  line-height: 1.5;
  color: var(--text-muted);
  background: var(--bg);
  border-radius: var(--radius-sm);
  padding: 8px 10px;
}

/* Stats modal */
#stats-modal .settings-dialog {
  width: 96%;
  max-width: 96%;
  max-height: 90vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.stats-content {
  padding: 16px;
  display: flex;
  flex-direction: column;
  align-items: stretch;
  gap: 20px;
  overflow-y: auto;
  flex: 1;
}

.stats-empty {
  color: var(--text-muted);
  text-align: center;
  padding: 12px 0;
}

.stats-subject {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.stats-subject-header {
  display: flex;
  align-items: center;
  gap: 8px;
}

.stats-subject-name {
  flex: 1;
  font-weight: 600;
}

.stats-subject-btns {
  display: flex;
  align-items: center;
  gap: 4px;
}

.stats-clear-subject {
  background: none;
  border: none;
  font-size: 0.8em;
  color: var(--text-muted);
  cursor: pointer;
  padding: 2px 6px;
  border-radius: 4px;
  font-family: inherit;
  transition: color 0.15s, background 0.15s;
  white-space: nowrap;
}

.stats-clear-subject:hover {
  color: var(--wrong);
  background: color-mix(in srgb, var(--wrong) 8%, transparent);
}

.stats-weak-btn {
  background: none;
  border: none;
  font-size: 0.8em;
  color: var(--primary);
  cursor: pointer;
  padding: 2px 6px;
  border-radius: 4px;
  font-family: inherit;
  transition: color 0.15s, background 0.15s;
  white-space: nowrap;
}

.stats-weak-btn:hover {
  background: color-mix(in srgb, var(--primary) 10%, transparent);
}

.stats-clear-btn {
  align-self: center;
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.85em;
  font-family: inherit;
  color: var(--text-muted);
  cursor: pointer;
  padding: 7px 16px;
  margin-top: 4px;
  transition: color 0.15s, border-color 0.15s;
}

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

.confirm-modal {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  z-index: 200;
  align-items: center;
  justify-content: center;
}

.confirm-modal.visible {
  display: flex;
}

.confirm-dialog {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  width: 80%;
  max-width: 320px;
  box-shadow: 0 8px 32px rgba(0,0,0,0.2);
  display: flex;
  flex-direction: column;
  gap: 16px;
  font-size: var(--msg-font);
}

.confirm-text {
  line-height: 1.5;
  color: var(--text);
}

.confirm-actions {
  display: flex;
  gap: 8px;
  justify-content: flex-end;
}

.confirm-btn {
  padding: 8px 16px;
  border-radius: var(--radius-sm);
  font-size: 0.9em;
  font-family: inherit;
  cursor: pointer;
  font-weight: 500;
  transition: background 0.15s, opacity 0.15s;
}

.confirm-btn--danger {
  background: var(--wrong);
  color: #fff;
  border: none;
}

.confirm-btn--danger:hover { opacity: 0.88; }

.confirm-btn--cancel {
  background: none;
  border: 1px solid var(--border);
  color: var(--text-muted);
}

.confirm-btn--cancel:hover { background: var(--border); }

.stats-tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 8px;
}

.stats-tab {
  background: none;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 0.8em;
  font-family: inherit;
  color: var(--text-muted);
  cursor: pointer;
  padding: 2px 10px;
  transition: all 0.15s;
}

.stats-tab--active {
  background: var(--primary);
  border-color: var(--primary);
  color: #fff;
}

.stats-topics {
  display: flex;
  flex-direction: column;
  gap: 5px;
  padding: 2px 0;
}

.stats-topics-empty {
  font-size: 0.85em;
  color: var(--text-muted);
  padding: 8px 0;
}

.stats-topic-row {
  display: flex;
  align-items: center;
  gap: 8px;
}

.stats-topic-name {
  font-size: 0.85em;
  width: 38%;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.stats-topic-bar-wrap {
  flex: 1;
  height: 8px;
  background: var(--border);
  border-radius: 4px;
  position: relative;
  overflow: visible;
}

.stats-topic-bar {
  height: 100%;
  border-radius: 4px;
  transition: width 0.3s ease;
}

.stats-topic-threshold {
  position: absolute;
  top: -3px;
  left: 75%;
  width: 2px;
  height: 14px;
  background: var(--text-muted);
  opacity: 0.4;
  border-radius: 1px;
}

.stats-topic-pct {
  font-size: 0.8em;
  font-weight: 600;
  width: 3.5em;
  text-align: right;
}

.stats-divider {
  font-size: 0.75em;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  padding-top: 12px;
}

.stats-student {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.stats-student-name {
  font-weight: 600;
}

.stats-correct { color: var(--correct); font-weight: 600; }
.stats-wrong   { color: var(--wrong);   font-weight: 600; }
.stats-skipped { color: var(--text-muted); font-weight: 600; }

.stats-legend {
  display: flex;
  align-items: center;
  gap: 6px;
  font-size: 0.75em;
  color: var(--text-muted);
  margin-top: 2px;
}

.stats-legend-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--primary);
  flex-shrink: 0;
}

.stats-summary {
  display: flex;
  gap: 6px;
  font-size: 0.85em;
  color: var(--text-muted);
  flex-wrap: wrap;
}

.stats-last {
  font-size: 0.8em;
  color: var(--text-muted);
  margin-bottom: 6px;
}

/* SVG chart */
.stats-chart {
  width: 100%;
  display: block;
}

.stats-grid {
  stroke: var(--border);
  stroke-width: 1;
}

.stats-axis-label {
  font-size: 9px;
  fill: var(--text-muted);
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

.stats-bar {
  cursor: default;
  transition: opacity 0.15s;
}

.stats-bar:hover {
  opacity: 1 !important;
}

.stats-tooltip {
  display: none;
  position: absolute;
  background: var(--text);
  color: var(--surface);
  border-radius: var(--radius-sm);
  padding: 7px 10px;
  font-size: 0.9em;
  line-height: 1.5;
  pointer-events: none;
  z-index: 10;
  white-space: nowrap;
  box-shadow: 0 2px 8px rgba(0,0,0,0.2);
}

.stats-tooltip.visible {
  display: block;
}

.stats-tip-date {
  font-weight: 600;
  margin-bottom: 4px;
  border-bottom: 1px solid rgba(255,255,255,0.15);
  padding-bottom: 4px;
}

.stats-tip-row {
  font-size: 0.9em;
  opacity: 0.9;
}

.stats-tip-row span {
  opacity: 0.65;
}

/* Scrollbar */
.messages::-webkit-scrollbar {
  width: 4px;
}
.messages::-webkit-scrollbar-track {
  background: transparent;
}
.messages::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 2px;
}