/* ===== CSS Variables ===== */
:root {
  --primary: #e85d04;
  --primary-dark: #c44d03;
  --primary-light: #fff3ed;
  --accent: #1a56db;
  --accent-dark: #1240ab;
  --accent-light: #e8f0fe;
  --success: #057a55;
  --success-light: #def7ec;
  --danger: #c81e1e;
  --danger-light: #fde8e8;
  --warning: #9f580a;
  --warning-light: #feecdc;
  --gray-50: #f9fafb;
  --gray-100: #f3f4f6;
  --gray-200: #e5e7eb;
  --gray-300: #d1d5db;
  --gray-400: #9ca3af;
  --gray-500: #6b7280;
  --gray-700: #374151;
  --gray-800: #1f2937;
  --gray-900: #111827;
  --bg: #f4f6f9;
  --card-bg: #fff;
  --header-bg: linear-gradient(135deg, #1a1f36 0%, #2d3561 100%);
  --radius: 14px;
  --radius-sm: 8px;
  --shadow: 0 1px 3px rgba(0,0,0,.08), 0 1px 2px rgba(0,0,0,.05);
  --shadow-md: 0 4px 12px rgba(0,0,0,.10);
  --shadow-lg: 0 10px 24px rgba(0,0,0,.12);
}

[data-theme="dark"] {
  --primary: #f4845f;
  --primary-dark: #e85d04;
  --primary-light: rgba(244,132,95,.12);
  --accent: #60a5fa;
  --accent-dark: #3b82f6;
  --accent-light: rgba(96,165,250,.12);
  --success: #34d399;
  --success-light: rgba(52,211,153,.12);
  --danger: #f87171;
  --danger-light: rgba(248,113,113,.12);
  --warning: #fbbf24;
  --warning-light: rgba(251,191,36,.12);
  --gray-50: #1e1e2e;
  --gray-100: #252536;
  --gray-200: #333348;
  --gray-300: #44445a;
  --gray-400: #6b6b80;
  --gray-500: #9ca3af;
  --gray-700: #d1d5db;
  --gray-800: #e5e7eb;
  --gray-900: #f3f4f6;
  --bg: #13131e;
  --card-bg: #1e1e2e;
  --header-bg: linear-gradient(135deg, #0f0f1a 0%, #1a1a30 100%);
  --shadow: 0 1px 3px rgba(0,0,0,.3);
  --shadow-md: 0 4px 12px rgba(0,0,0,.4);
  --shadow-lg: 0 10px 24px rgba(0,0,0,.5);
}

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

body {
  font-family: 'Noto Sans TC', -apple-system, BlinkMacSystemFont, sans-serif;
  background: var(--bg);
  color: var(--gray-900);
  line-height: 1.6;
  min-height: 100vh;
  transition: background-color .25s, color .25s;
}

a { color: inherit; text-decoration: none; }

/* ===== Header ===== */
.site-header {
  background: var(--header-bg);
  color: #fff;
  padding: 0 24px;
  box-shadow: 0 2px 12px rgba(0,0,0,.2);
  position: sticky;
  top: 0;
  z-index: 100;
}

.site-header .inner {
  max-width: 880px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 14px;
  height: 64px;
}

.header-logo-wrap { flex-shrink: 0; }

.header-logo-svg {
  width: 28px;
  height: 28px;
  stroke: var(--primary);
}

.site-header h1 {
  font-size: 1.05rem;
  font-weight: 700;
  letter-spacing: .02em;
}

.header-sub {
  font-size: .75rem;
  opacity: .6;
  margin-top: 1px;
}

.theme-toggle {
  margin-left: auto;
  background: rgba(255,255,255,.1);
  border: none;
  border-radius: 50%;
  width: 36px;
  height: 36px;
  font-size: 1.1rem;
  cursor: pointer;
  transition: all .2s;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.theme-toggle:hover {
  background: rgba(255,255,255,.2);
  transform: scale(1.1);
}

/* ===== Leitner Box Bar ===== */
.box-bar {
  background: var(--card-bg);
  border-bottom: 1px solid var(--gray-200);
  padding: 10px 16px;
  position: sticky;
  top: 64px;
  z-index: 90;
  box-shadow: var(--shadow);
}

.box-bar .inner {
  max-width: 880px;
  margin: 0 auto;
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: center;
}

.box-capsule {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border-radius: 99px;
  font-size: .8rem;
  font-weight: 500;
  border: 1.5px solid;
}

.box-capsule .box-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
}

.box-capsule .box-label {
  color: var(--gray-500);
}

.box-capsule .box-count {
  font-weight: 700;
}

.box-capsule.box1 {
  background: var(--danger-light);
  border-color: var(--danger);
  color: var(--danger);
}
.box-capsule.box1 .box-dot { background: var(--danger); }

.box-capsule.box2 {
  background: var(--warning-light);
  border-color: var(--warning);
  color: var(--warning);
}
.box-capsule.box2 .box-dot { background: var(--warning); }

.box-capsule.box3 {
  background: var(--success-light);
  border-color: var(--success);
  color: var(--success);
}
.box-capsule.box3 .box-dot { background: var(--success); }

.box-capsule.unseen {
  background: var(--gray-100);
  border-color: var(--gray-300);
  color: var(--gray-500);
}
.box-capsule.unseen .box-dot { background: var(--gray-400); }

/* ===== Main Container ===== */
.container {
  max-width: 880px;
  margin: 0 auto;
  padding: 32px 16px 48px;
}

/* ===== Selector Card ===== */
.selector-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
  padding: 32px 28px;
  margin-bottom: 24px;
}

.selector-header { margin-bottom: 24px; }

.selector-header h2 {
  font-size: 1.3rem;
  font-weight: 700;
  color: var(--gray-900);
  margin-bottom: 6px;
}

.selector-header p {
  font-size: .92rem;
  color: var(--gray-500);
}

/* ===== Blind Mode Toggle ===== */
.blind-toggle-row {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 16px;
  background: var(--accent-light);
  border: 1.5px solid var(--accent);
  border-radius: var(--radius-sm);
  margin-bottom: 20px;
}

.blind-toggle {
  position: relative;
  width: 44px;
  height: 24px;
  flex-shrink: 0;
}

.blind-toggle input {
  opacity: 0;
  width: 0;
  height: 0;
}

.blind-slider {
  position: absolute;
  cursor: pointer;
  inset: 0;
  background: var(--gray-300);
  border-radius: 24px;
  transition: .3s;
}

.blind-slider::before {
  content: "";
  position: absolute;
  height: 18px;
  width: 18px;
  left: 3px;
  bottom: 3px;
  background: white;
  border-radius: 50%;
  transition: .3s;
}

.blind-toggle input:checked + .blind-slider {
  background: var(--accent);
}

.blind-toggle input:checked + .blind-slider::before {
  transform: translateX(20px);
}

.blind-info {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.blind-info strong {
  font-size: .9rem;
  color: var(--accent);
}

.blind-info span {
  font-size: .78rem;
  color: var(--gray-500);
}

/* ===== Select ===== */
.select-label {
  display: block;
  font-size: .85rem;
  font-weight: 600;
  color: var(--gray-700);
  margin-bottom: 8px;
}

.custom-select-wrap {
  position: relative;
  margin-bottom: 16px;
}

.custom-select-wrap select {
  width: 100%;
  appearance: none;
  -webkit-appearance: none;
  background: var(--gray-50);
  border: 1.5px solid var(--gray-200);
  border-radius: var(--radius-sm);
  padding: 14px 48px 14px 18px;
  font-size: 1rem;
  font-weight: 500;
  line-height: 1.4;
  min-height: 52px;
  font-family: inherit;
  color: var(--gray-900);
  cursor: pointer;
  outline: none;
  transition: border-color .15s, box-shadow .15s;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 24 24' fill='none' stroke='%236b7280' stroke-width='2'%3E%3Cpath d='M6 9l6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 16px center;
}

.custom-select-wrap select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(232,93,4,.12);
}

/* ===== User Info Row ===== */
.user-info-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 10px;
  padding: 0 4px;
}

.user-last-practice {
  font-size: .82rem;
  color: var(--gray-500);
}

.btn-reset {
  padding: 6px 14px;
  font-size: .8rem;
  background: var(--danger-light);
  color: var(--danger);
  border: 1.5px solid var(--danger);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all .15s;
  font-family: inherit;
  font-weight: 600;
}

.btn-reset:hover {
  background: var(--danger);
  color: #fff;
}

/* ===== Mode Selector ===== */
.mode-select { margin-bottom: 16px; }

.mode-options {
  display: flex;
  gap: 10px;
}

.mode-radio {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 4px;
  padding: 14px 12px;
  border: 1.5px solid var(--gray-200);
  border-radius: var(--radius-sm);
  cursor: pointer;
  background: var(--gray-50);
  transition: all .15s;
  text-align: center;
}

.mode-radio input { display: none; }

.mode-radio:hover { border-color: var(--primary); }

.mode-radio.active {
  border-color: var(--primary);
  background: var(--primary-light);
  box-shadow: 0 0 0 2px rgba(232,93,4,.15);
}

.mode-icon { font-size: 1.4rem; }

.mode-label {
  font-size: .88rem;
  font-weight: 700;
  color: var(--gray-900);
}

.mode-desc {
  font-size: .72rem;
  color: var(--gray-500);
}

/* ===== Buttons ===== */
.btn {
  padding: 10px 22px;
  border-radius: var(--radius-sm);
  font-size: .9rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: all .15s;
  font-family: inherit;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}

.btn:disabled { opacity: .4; cursor: not-allowed; }

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

.btn-primary:hover:not(:disabled) {
  background: var(--primary-dark);
  box-shadow: 0 4px 12px rgba(232,93,4,.3);
}

.btn-outline {
  background: var(--card-bg);
  border: 1.5px solid var(--gray-300);
  color: var(--gray-700);
}

.btn-outline:hover:not(:disabled) {
  border-color: var(--primary);
  color: var(--primary);
}

.btn-start {
  width: 100%;
  justify-content: center;
  padding: 14px;
  font-size: 1rem;
  border-radius: var(--radius-sm);
  letter-spacing: .03em;
}

/* ===== Reveal Button (Blind Mode) ===== */
.btn-reveal {
  width: 100%;
  justify-content: center;
  padding: 16px;
  font-size: 1rem;
  background: var(--accent);
  color: #fff;
  border-radius: var(--radius-sm);
  margin-bottom: 16px;
  animation: pulse 2s infinite;
}

.btn-reveal:hover {
  background: var(--accent-dark);
  animation: none;
}

@keyframes pulse {
  0%, 100% { box-shadow: 0 0 0 0 rgba(26,86,219,.3); }
  50% { box-shadow: 0 0 0 8px rgba(26,86,219,0); }
}

/* ===== Confirm Row (Confidence Calibration) ===== */
.confirm-row {
  display: flex;
  gap: 10px;
  margin-top: 16px;
  animation: slideUp .2s ease;
}

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

.btn-confirm {
  flex: 1;
  justify-content: center;
  padding: 12px;
  background: var(--success);
  color: #fff;
  font-size: .92rem;
  transition: all .15s;
}

.btn-confirm:hover:not(:disabled) {
  background: #046a4a;
  box-shadow: 0 4px 12px rgba(5,122,85,.3);
}

.btn-confirm.active {
  background: var(--success);
  box-shadow: 0 0 0 3px rgba(5,122,85,.3);
}

.btn-confirm.dimmed {
  opacity: .4;
}

.btn-guess {
  flex: 1;
  justify-content: center;
  padding: 12px;
  background: var(--warning);
  color: #fff;
  font-size: .92rem;
  transition: all .15s;
}

.btn-guess:hover:not(:disabled) {
  background: #8a4d08;
  box-shadow: 0 4px 12px rgba(159,88,10,.3);
}

.btn-guess.active {
  background: var(--warning);
  box-shadow: 0 0 0 3px rgba(159,88,10,.3);
}

.btn-guess.dimmed {
  opacity: .4;
}

/* ===== Exam Header ===== */
.exam-header {
  background: var(--card-bg);
  border-bottom: 1px solid var(--gray-200);
  padding: 10px 16px;
  position: sticky;
  top: 108px;
  z-index: 85;
  box-shadow: var(--shadow);
}

.exam-header .inner {
  max-width: 880px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.exam-meta {
  display: flex;
  gap: 12px;
  align-items: center;
  font-size: .85rem;
  color: var(--gray-500);
}

.exam-meta strong { color: var(--gray-900); }

#exam-timer { font-variant-numeric: tabular-nums; }
#exam-timer.timer-warning { color: var(--danger); animation: timer-pulse 1s ease-in-out infinite; }
@keyframes timer-pulse { 0%, 100% { opacity: 1; } 50% { opacity: 0.5; } }

.progress-bar-wrap {
  flex: 1;
  min-width: 120px;
  background: var(--gray-200);
  border-radius: 99px;
  height: 6px;
  overflow: hidden;
}

.progress-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--primary), #f4a261);
  border-radius: 99px;
  transition: width .3s ease;
}

.btn-end-early {
  margin-left: auto;
  background: none;
  border: 1.5px solid var(--danger);
  color: var(--danger);
  border-radius: var(--radius-sm);
  padding: 5px 12px;
  font-size: .82rem;
  cursor: pointer;
  transition: all .2s;
  white-space: nowrap;
  font-family: inherit;
}

.btn-end-early:hover {
  background: var(--danger);
  color: #fff;
}

/* ===== Question Card ===== */
.question-wrap {
  max-width: 720px;
  margin: 28px auto;
  padding: 0 16px;
}

.question-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow-md);
  padding: 28px 28px 20px;
  margin-bottom: 16px;
}

.q-top-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 10px;
}

.q-number {
  font-size: .8rem;
  font-weight: 600;
  color: var(--primary);
  text-transform: uppercase;
  letter-spacing: .05em;
}

.q-cat {
  font-size: .75rem;
  color: var(--gray-400);
  background: var(--gray-100);
  padding: 2px 8px;
  border-radius: 4px;
}

.q-text {
  font-size: 1.05rem;
  font-weight: 500;
  line-height: 1.7;
  margin-bottom: 20px;
}

.q-image {
  text-align: center;
  margin: -8px 0 16px;
}

.q-image img {
  max-width: 100%;
  max-height: 300px;
  border: 1px solid var(--gray-200);
  border-radius: 8px;
  cursor: zoom-in;
  background: #fff;
  padding: 4px;
}

/* ===== Options ===== */
.options-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.options-list.options-hidden {
  display: none;
}

.option-btn {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 13px 16px;
  border: 1.5px solid var(--gray-200);
  border-radius: var(--radius-sm);
  background: var(--gray-50);
  cursor: pointer;
  text-align: left;
  font-size: .95rem;
  line-height: 1.5;
  transition: all .15s;
  width: 100%;
  font-family: inherit;
  color: var(--gray-900);
}

.option-btn:hover:not(:disabled) {
  border-color: var(--primary);
  background: var(--primary-light);
}

.option-label {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  background: var(--gray-200);
  border-radius: 50%;
  font-size: .8rem;
  font-weight: 700;
  flex-shrink: 0;
  margin-top: 1px;
  transition: all .15s;
}

.option-btn:hover:not(:disabled) .option-label {
  background: var(--primary);
  color: #fff;
}

.option-btn.selected {
  border-color: var(--primary);
  background: var(--primary-light);
}

.option-btn.selected .option-label {
  background: var(--primary);
  color: #fff;
}

.option-btn.correct {
  border-color: var(--success);
  background: var(--success-light);
}

.option-btn.correct .option-label {
  background: var(--success);
  color: #fff;
}

.option-btn.wrong {
  border-color: var(--danger);
  background: var(--danger-light);
}

.option-btn.wrong .option-label {
  background: var(--danger);
  color: #fff;
}

.option-btn:disabled {
  cursor: default;
  opacity: .85;
}

/* ===== Answer Hint ===== */
.answer-hint {
  margin-top: 14px;
  font-size: .88rem;
  padding: 12px 14px;
  border-radius: var(--radius-sm);
  display: none;
  line-height: 1.6;
}

.answer-hint.show { display: block; }

.answer-hint.correct {
  background: var(--success-light);
  color: var(--success);
}

.answer-hint.wrong {
  background: var(--danger-light);
  color: var(--danger);
}

.answer-hint .hint-answer {
  font-weight: 700;
  display: block;
  margin-bottom: 4px;
}

.answer-hint .hint-exp {
  font-size: .84rem;
  opacity: .85;
  line-height: 1.7;
}

.answer-hint .hint-exp .exp-line {
  display: block;
  margin-bottom: 4px;
}

.exp-table {
  width: 100%;
  border-collapse: collapse;
  margin: 8px 0;
  font-size: .8rem;
}

.exp-table th,
.exp-table td {
  border: 1px solid var(--border);
  padding: 6px 10px;
  text-align: left;
}

.exp-table th {
  background: var(--bg-card);
  font-weight: 600;
}

.exp-table tr:nth-child(even) td {
  background: var(--bg-hover);
}

/* ===== Question Navigator ===== */
.qnav-wrap {
  max-width: 720px;
  margin: 0 auto 16px;
  padding: 0 16px;
  display: block;
}

/* 手機（<768px）：題目導覽預設收合（由 JS initQnavMobileDefault() 加上 collapsed），收合時縮小邊距 */
@media (max-width: 767px) {
  .qnav-wrap.collapsed {
    margin-bottom: 8px;
  }
}

.qnav-toggle {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 16px;
  background: var(--card-bg);
  border: 1.5px solid var(--gray-200);
  border-radius: var(--radius-sm);
  cursor: pointer;
  font-family: inherit;
  font-size: .88rem;
  font-weight: 600;
  color: var(--gray-700);
  transition: all .15s;
}

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

.qnav-toggle-icon {
  display: inline-block;
  transition: transform .2s;
  font-size: .75rem;
}

.qnav-wrap.collapsed .qnav-toggle-icon {
  transform: rotate(-90deg);
}

.qnav-toggle-count {
  margin-left: auto;
  font-size: .78rem;
  font-weight: 500;
  color: var(--gray-400);
}

.qnav-panel {
  background: var(--card-bg);
  border: 1.5px solid var(--gray-200);
  border-top: none;
  border-radius: 0 0 var(--radius-sm) var(--radius-sm);
  padding: 14px 16px;
  transition: all .25s ease;
  opacity: 1;
}

.qnav-wrap.collapsed .qnav-panel {
  display: none;
}

.qnav-legend {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 12px;
  font-size: .75rem;
  color: var(--gray-500);
}

.qnav-legend-item {
  display: flex;
  align-items: center;
  gap: 4px;
}

.qnav-dot {
  width: 10px;
  height: 10px;
  border-radius: 3px;
  flex-shrink: 0;
}

.qnav-dot.current { background: var(--accent); }
.qnav-dot.correct { background: var(--success); }
.qnav-dot.wrong { background: var(--danger); }
.qnav-dot.selected { background: var(--warning); }
.qnav-dot.unanswered { background: var(--gray-300); }

.qnav-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(36px, 1fr));
  gap: 6px;
  max-height: 280px;
  overflow-y: auto !important;
  -webkit-overflow-scrolling: touch;
  touch-action: pan-y;
  scrollbar-width: thin;
  padding-right: 4px;
}

.qnav-btn {
  width: 100%;
  aspect-ratio: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1.5px solid var(--gray-200);
  border-radius: 6px;
  background: var(--gray-50);
  font-family: inherit;
  font-size: .78rem;
  font-weight: 600;
  color: var(--gray-500);
  cursor: pointer;
  transition: all .12s;
  padding: 0;
}

.qnav-btn:hover:not(.current) {
  border-color: var(--primary);
  color: var(--primary);
  background: var(--primary-light);
}

.qnav-btn.current {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  box-shadow: 0 0 0 2px rgba(26,86,219,.25);
}

.qnav-btn.correct {
  background: var(--success-light);
  border-color: var(--success);
  color: var(--success);
}

.qnav-btn.wrong {
  background: var(--danger-light);
  border-color: var(--danger);
  color: var(--danger);
}

.qnav-btn.selected {
  background: var(--warning-light);
  border-color: var(--warning);
  color: var(--warning);
}

.qnav-btn.unanswered {
  background: var(--gray-50);
  border-color: var(--gray-200);
  color: var(--gray-400);
}

/* ===== Flag Row (Explanation Error Report) ===== */
.flag-row {
  margin-top: 10px;
  display: flex;
  justify-content: flex-end;
}

.btn-flag {
  padding: 6px 14px;
  font-size: .8rem;
  font-weight: 600;
  font-family: inherit;
  background: var(--gray-100);
  color: var(--gray-500);
  border: 1.5px solid var(--gray-300);
  border-radius: var(--radius-sm);
  cursor: pointer;
  transition: all .15s;
}

.btn-flag:hover {
  border-color: var(--danger);
  color: var(--danger);
  background: var(--danger-light);
}

.btn-flag.flagged {
  background: var(--danger);
  color: #fff;
  border-color: var(--danger);
}

/* ===== Action Row ===== */
.action-row {
  display: none;
}

/* ===== Question Nav Row ===== */
.q-nav-row {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  padding: 12px 0;
  margin-bottom: 12px;
}

.q-nav-row .btn-nav {
  min-width: 120px;
  justify-content: center;
  padding: 10px 20px;
  font-size: 0.95rem;
}

.q-nav-row .btn-nav:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

/* ===== Result Card ===== */
.result-card {
  background: var(--card-bg);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  padding: 36px 28px;
  max-width: 680px;
  margin: 0 auto 28px;
  text-align: center;
}

.score-circle {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  margin: 0 auto 20px;
  font-weight: 700;
}

.score-circle.pass {
  background: var(--success-light);
  color: var(--success);
  border: 4px solid var(--success);
}

.score-circle.fail {
  background: var(--danger-light);
  color: var(--danger);
  border: 4px solid var(--danger);
}

.score-num { font-size: 2.4rem; line-height: 1; }

.score-label { font-size: .75rem; margin-top: 2px; }

.pass-badge {
  display: inline-block;
  padding: 4px 14px;
  border-radius: 99px;
  font-size: .85rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.pass-badge.pass {
  background: var(--success-light);
  color: var(--success);
}

.pass-badge.fail {
  background: var(--danger-light);
  color: var(--danger);
}

.stats-row {
  display: flex;
  justify-content: center;
  gap: 28px;
  font-size: .9rem;
  color: var(--gray-500);
  margin-bottom: 24px;
  flex-wrap: wrap;
}

.stats-row span strong { color: var(--gray-900); }

.result-actions {
  display: flex;
  gap: 12px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ===== Wrong List ===== */
.wrong-list {
  max-width: 720px;
  margin: 0 auto;
  padding: 0 16px;
}

.wrong-list h2 {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: 16px;
}

.wrong-item {
  background: var(--card-bg);
  border-radius: var(--radius-sm);
  border: 1.5px solid var(--danger-light);
  padding: 16px 18px;
  margin-bottom: 12px;
}

.wrong-item .wi-num {
  font-size: .8rem;
  color: var(--danger);
  font-weight: 700;
  margin-bottom: 6px;
}

.wrong-item .wi-q {
  font-size: .95rem;
  margin-bottom: 10px;
  line-height: 1.6;
}

.wrong-item .wi-meta {
  font-size: .82rem;
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.wi-your { color: var(--danger); }
.wi-correct { color: var(--success); }
.wi-guess { color: var(--warning); font-style: italic; }

.wrong-item .wi-exp {
  margin-top: 10px;
  padding: 10px 14px;
  background: var(--bg-card);
  border-left: 3px solid var(--accent);
  border-radius: 0 8px 8px 0;
  font-size: .85rem;
  line-height: 1.7;
  color: var(--text-secondary);
}

.wrong-item .wi-exp .exp-line {
  display: block;
  margin-bottom: 4px;
}

.wrong-item .wi-exp .exp-table {
  width: 100%;
  border-collapse: collapse;
  margin: 8px 0;
  font-size: .8rem;
}

.wrong-item .wi-exp .exp-table th,
.wrong-item .wi-exp .exp-table td {
  border: 1px solid var(--border);
  padding: 6px 10px;
  text-align: left;
}

.wrong-item .wi-exp .exp-table th {
  background: var(--bg-hover);
  font-weight: 600;
}

/* ===== Image Modal ===== */
.image-modal {
  display: none;
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(0,0,0,.85);
  align-items: center;
  justify-content: center;
  flex-direction: column;
  cursor: pointer;
}

.image-modal.show { display: flex; }

.image-modal img {
  max-width: 90vw;
  max-height: 85vh;
  border-radius: 8px;
  background: #fff;
  padding: 8px;
}

.image-modal-hint {
  color: rgba(255,255,255,.6);
  font-size: .85rem;
  margin-top: 12px;
}

/* ===== Toast ===== */
.toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(80px);
  background: var(--gray-800);
  color: #fff;
  padding: 10px 20px;
  border-radius: var(--radius-sm);
  font-size: .9rem;
  z-index: 300;
  transition: transform .3s ease;
  pointer-events: none;
  white-space: nowrap;
}

[data-theme="dark"] .toast {
  background: var(--gray-100);
  color: var(--gray-900);
}

.toast.show {
  transform: translateX(-50%) translateY(0);
}

/* ===== Footer ===== */
.site-footer {
  text-align: center;
  padding: 24px 16px 32px;
  font-size: .78rem;
  color: var(--gray-400);
  line-height: 1.6;
}

.footer-org {
  font-size: .82rem;
  color: var(--gray-500);
  font-weight: 500;
  margin-bottom: 4px;
}

/* ===== Responsive ===== */
@media (max-width: 640px) {
  .container { padding: 20px 12px 32px; }
  .selector-card { padding: 24px 18px; }
  .question-card { padding: 20px 16px 16px; }
  .mode-options { flex-direction: column; }
  .box-bar .inner { gap: 6px; }
  .box-capsule { padding: 4px 8px; font-size: .72rem; }
  .box-capsule .box-label { display: none; }
  .exam-header .inner { gap: 8px; }
  .exam-meta { font-size: .78rem; gap: 8px; }
  .confirm-row { flex-direction: column; }
}