/* ═════════════════════════════════════════════════════════════
   QUIZ INTERFACE — Azota Style
   ═════════════════════════════════════════════════════════════ */

/* Quiz Header (shared by topics and quiz screens) */
.quiz-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 14px 20px;
  margin-bottom: 20px;
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  flex-wrap: wrap;
  gap: 10px;
}

.back-btn {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 0.88rem;
  cursor: pointer;
  font-family: inherit;
  padding: 6px 10px;
  display: inline-flex;
  align-items: center;
  gap: 4px;
  transition: var(--transition);
  border-radius: var(--radius-sm);
}

.back-btn:hover {
  color: var(--primary);
  background: var(--primary-soft);
}

.quiz-info {
  display: flex;
  gap: 8px;
  align-items: center;
}

.subject-badge {
  padding: 5px 12px;
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 600;
  background: var(--primary-soft);
  border: 1px solid var(--primary-border);
  color: var(--primary);
}

.progress-badge {
  padding: 5px 12px;
  border-radius: var(--radius-full);
  font-size: 0.78rem;
  font-weight: 600;
  background: var(--bg-gray);
  border: 1px solid var(--border);
  color: var(--text-secondary);
}

/* Timer */
.timer {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  background: var(--bg-gray);
  border: 1px solid var(--border);
  border-radius: var(--radius-full);
  font-size: 0.95rem;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
  color: var(--text-primary);
}

.timer.warning {
  border-color: var(--orange);
  background: var(--orange-bg);
  color: var(--orange);
}

.timer.danger {
  border-color: var(--red);
  background: var(--red-bg);
  color: var(--red);
  animation: pulse 1s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.5; }
}

.timer-icon { font-size: 1rem; }

/* ═════════════════════════════════════════════════════════════
   QUIZ LAYOUT (Sidebar + Main)
   ═════════════════════════════════════════════════════════════ */

.quiz-layout {
  display: grid;
  grid-template-columns: 170px 1fr;
  gap: 16px;
}

/* Sidebar */
.quiz-sidebar {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px;
  height: fit-content;
  position: sticky;
  top: 80px;
}

.sidebar-header {
  font-size: 0.8rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 10px;
  text-align: center;
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.question-dots {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 6px;
}

.q-dot {
  width: 38px;
  height: 38px;
  border-radius: var(--radius-sm);
  font-size: 0.78rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  border: 1.5px solid var(--border);
  background: var(--bg-white);
  color: var(--text-muted);
  transition: var(--transition);
}

.q-dot:hover {
  border-color: var(--primary-border);
  color: var(--primary);
}

.q-dot.current {
  border-color: var(--primary);
  background: var(--primary);
  color: #fff;
}

.q-dot.answered {
  border-color: var(--primary-border);
  background: var(--primary-soft);
  color: var(--primary);
}

/* ═════════════════════════════════════════════════════════════
   QUESTION CARD
   ═════════════════════════════════════════════════════════════ */

.quiz-main { min-width: 0; }

.question-card {
  background: var(--bg-white);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  position: relative;
  overflow: hidden;
}

.question-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: var(--primary);
}

/* Question Meta */
.question-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 14px;
}

.question-type-badge {
  padding: 3px 10px;
  border-radius: var(--radius-full);
  font-size: 0.68rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.4px;
  background: var(--primary-soft);
  color: var(--primary);
}

.question-type-badge.tf {
  background: var(--blue-bg);
  color: var(--blue);
}

.question-number {
  font-size: 0.82rem;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.8px;
}

.question-text {
  font-size: 1.05rem;
  line-height: 1.7;
  font-weight: 500;
  margin-bottom: 24px;
  color: var(--text-primary);
}

/* ═════════════════════════════════════════════════════════════
   ANSWER OPTIONS
   ═════════════════════════════════════════════════════════════ */

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

.option {
  padding: 14px 18px;
  border-radius: var(--radius-sm);
  background: var(--bg-gray);
  border: 1.5px solid transparent;
  color: var(--text-primary);
  font-size: 0.92rem;
  cursor: pointer;
  transition: var(--transition);
  text-align: left;
  font-family: inherit;
  display: flex;
  align-items: center;
  gap: 12px;
}

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

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

.option.correct {
  border-color: var(--green);
  background: var(--green-bg);
}

.option.incorrect {
  border-color: var(--red);
  background: var(--red-bg);
}

.option:disabled {
  cursor: not-allowed;
  opacity: 0.92;
}

/* Option Letter */
.option-letter {
  width: 30px;
  height: 30px;
  border-radius: 7px;
  flex-shrink: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.82rem;
  font-weight: 700;
  background: var(--bg-white);
  border: 1.5px solid var(--border);
  transition: var(--transition);
  color: var(--text-secondary);
}

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

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

.option.correct .option-letter {
  background: var(--green);
  border-color: var(--green);
  color: #fff;
}

.option.incorrect .option-letter {
  background: var(--red);
  border-color: var(--red);
  color: #fff;
}

/* ═════════════════════════════════════════════════════════════
   TF GROUP QUESTION (Passage + Statements)
   ═════════════════════════════════════════════════════════════ */

.question-passage {
  background: var(--bg-gray);
  border-left: 3px solid var(--primary);
  padding: 14px 16px;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 0.88rem;
  line-height: 1.75;
  color: var(--text-secondary);
  margin-bottom: 18px;
  max-height: 220px;
  overflow-y: auto;
  white-space: pre-wrap;
}

.tf-statement {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background: var(--bg-gray);
  border-radius: var(--radius-sm);
  margin-bottom: 8px;
  border: 1.5px solid transparent;
  transition: var(--transition);
}

.tf-statement:hover {
  border-color: var(--border-hover);
}

.tf-statement-text {
  flex: 1;
  font-size: 0.9rem;
  line-height: 1.5;
  color: var(--text-primary);
}

.tf-buttons {
  display: flex;
  gap: 6px;
  flex-shrink: 0;
}

.tf-btn {
  padding: 6px 16px;
  border-radius: var(--radius-full);
  border: 1.5px solid var(--border);
  background: var(--bg-white);
  color: var(--text-secondary);
  font-size: 0.8rem;
  font-weight: 600;
  font-family: inherit;
  cursor: pointer;
  transition: var(--transition);
  min-width: 56px;
  text-align: center;
}

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

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

/* TF dot in sidebar */
.q-dot.tf-dot {
  font-size: 0.68rem;
}

/* Review styles for TF groups */
.review-item.tf-review {
  border-left-color: var(--blue);
}

.review-passage-short {
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 8px;
  padding: 8px;
  background: var(--bg-page);
  border-radius: var(--radius-xs);
  line-height: 1.5;
}

.review-tf-statement {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 8px;
  border-radius: var(--radius-xs);
  font-size: 0.82rem;
  margin-bottom: 4px;
  flex-wrap: wrap;
}

.review-tf-statement.correct {
  background: var(--green-bg);
}

.review-tf-statement.wrong {
  background: var(--red-bg);
}

.review-tf-label {
  font-weight: 700;
  color: var(--text-secondary);
  flex-shrink: 0;
}

.review-tf-answer {
  margin-left: auto;
  font-weight: 600;
  font-size: 0.78rem;
  flex-shrink: 0;
}

.review-tf-statement.correct .review-tf-answer { color: var(--green); }
.review-tf-statement.wrong .review-tf-answer { color: var(--red); }

/* ═════════════════════════════════════════════════════════════
   QUIZ NAVIGATION
   ═════════════════════════════════════════════════════════════ */

.quiz-nav {
  display: flex;
  justify-content: space-between;
  margin-top: 20px;
  gap: 10px;
  flex-wrap: wrap;
}

.nav-btn {
  padding: 10px 24px;
  font-size: 0.88rem;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  font-family: inherit;
  transition: var(--transition);
  display: flex;
  align-items: center;
  gap: 6px;
}

.nav-btn.prev {
  background: var(--bg-gray);
  border: 1.5px solid var(--border);
  color: var(--text-primary);
}

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

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

.nav-btn.next:hover:not(:disabled) {
  background: var(--primary-dark);
}

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

.nav-btn.submit:hover:not(:disabled) {
  background: var(--primary-dark);
}

.nav-btn:hover:not(:disabled) {
  transform: translateY(-1px);
}

.nav-btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
  transform: none;
}

/* ═════════════════════════════════════════════════════════════
   RESPONSIVE
   ═════════════════════════════════════════════════════════════ */

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

  .quiz-sidebar {
    position: static;
    order: 2;
  }

  .question-dots {
    grid-template-columns: repeat(6, 1fr);
    gap: 8px; /* larger gap for touch */
  }

  .q-dot {
    width: 38px;
    height: 38px;
    font-size: 0.8rem;
  }

  .question-card {
    padding: 24px 16px;
  }

  .question-text {
    font-size: 1.1rem;
    line-height: 1.5;
  }

  .option, .study-tf-stmt {
    padding: 16px; /* bigger touch target */
    font-size: 1rem;
    margin-bottom: 12px;
  }

  .nav-btn {
    padding: 14px 20px; /* taller buttons on mobile */
    font-size: 1rem;
  }

  .quiz-header {
    flex-direction: column;
    align-items: stretch;
    padding: 12px 14px;
  }

  .quiz-info { justify-content: center; }
  .timer { justify-content: center; }
}

@media (max-width: 480px) {
  .question-dots {
    grid-template-columns: repeat(5, 1fr);
  }

  .q-dot {
    width: 36px;
    height: 36px;
    font-size: 0.8rem;
  }

  .nav-btn {
    padding: 12px 18px;
    font-size: 0.95rem;
  }

  /* Stack practice header nav buttons if narrow */
  .practice-header {
    flex-wrap: wrap;
    gap: 10px;
  }
}

/* ═════════════════════════════════════════════════════════════
   SHORT ANSWER (Trả Lời Ngắn)
   ═════════════════════════════════════════════════════════════ */
.question-type-badge.sa {
  background: var(--purple-bg, #f3e8ff);
  color: var(--purple, #9333ea);
}

.sa-dot {
  border-radius: 50% !important; /* Make it distinct from MCQ and TF dots */
}

.study-badge.sa {
  background: var(--purple-bg, #f3e8ff);
  color: var(--purple, #9333ea);
  display: inline-block;
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 700;
  margin-bottom: 15px;
}

.sa-container {
  padding: 10px 0;
}

.sa-input {
  width: 100%;
  padding: 16px 20px;
  border: 2px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 1.05rem;
  font-family: inherit;
  color: var(--text-primary);
  background: var(--bg-gray);
  transition: var(--transition);
}

.sa-input:focus {
  outline: none;
  border-color: var(--primary);
  background: var(--bg-white);
  box-shadow: 0 0 0 4px var(--primary-soft);
}

/* Practice Mode SA */
.practice-sa-container {
  margin-top: 15px;
  display: flex;
  flex-direction: column;
  gap: 15px;
}

.sa-input-wrapper {
  display: flex;
  gap: 10px;
}

.practice-sa-btn {
  padding: 0 24px;
  background: var(--primary);
  color: white;
  border: none;
  border-radius: var(--radius-sm);
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
}

.practice-sa-btn:hover {
  background: var(--primary-hover);
}

.practice-sa-result {
  padding: 16px;
  border-radius: var(--radius-sm);
  background: var(--bg-gray);
  border: 1px solid var(--border);
}

.practice-sa-result.correct {
  background: var(--green-bg);
  border-color: var(--green);
}

.practice-sa-result.wrong {
  background: var(--red-bg);
  border-color: var(--red);
}

.practice-sa-input-readonly {
  font-size: 1.05rem;
  font-weight: 500;
  margin-bottom: 8px;
  padding: 8px 12px;
  background: rgba(255, 255, 255, 0.5);
  border-radius: 4px;
}

.practice-sa-correct-ans {
  margin-top: 10px;
  font-size: 0.95rem;
  color: var(--text-secondary);
}

.fc-type.sa {
  color: var(--purple, #9333ea);
  background: var(--purple-bg, #f3e8ff);
  display: inline-block;
  padding: 4px 12px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 700;
  margin-bottom: 15px;
}