/* ===========================
   Part Quiz — 理解度チェック
=========================== */

.part-quiz {
  border-top: 1px solid var(--color-border);
  padding: 48px 0 40px;
}

.part-quiz .container--narrow {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

/* Head */
.part-quiz__head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-bottom: 20px;
  border-bottom: 1px solid var(--color-border);
}

.part-quiz__title {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--color-primary);
}

.part-quiz__count {
  font-size: 12px;
  color: var(--color-text-muted);
}

/* Question list */
.part-quiz__questions {
  display: flex;
  flex-direction: column;
  gap: 32px;
}

/* Individual question */
.part-quiz__question {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.part-quiz__q-meta {
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.part-quiz__q-num {
  flex-shrink: 0;
  width: 26px;
  height: 26px;
  border-radius: 50%;
  border: 1.5px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 11px;
  font-weight: 700;
  color: var(--color-text-muted);
  margin-top: 2px;
  transition: background 0.2s, border-color 0.2s, color 0.2s;
}

.part-quiz__q-text {
  font-size: 15px;
  font-weight: 700;
  line-height: 1.55;
  color: var(--color-text);
}

/* Options grid */
.part-quiz__options {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  padding-left: 38px;
}
@media (max-width: 600px) {
  .part-quiz__options { grid-template-columns: 1fr; padding-left: 0; }
}

.part-quiz__option {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  padding: 14px 16px;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  background: #fff;
  text-align: left;
  cursor: pointer;
  font-family: var(--font-sans);
  font-size: 14px;
  color: var(--color-text);
  transition: border-color 0.18s, background 0.18s, transform 0.18s;
  line-height: 1.5;
}
.part-quiz__option:hover:not([disabled]) {
  border-color: var(--color-primary-light);
  background: var(--color-primary-bg);
  transform: translateX(2px);
}
.part-quiz__option.is-selected {
  border-color: var(--color-primary);
  background: var(--color-primary-bg);
}
.part-quiz__option.is-correct {
  border-color: var(--color-primary);
  background: var(--color-primary-bg);
  cursor: default;
  transform: none;
}
.part-quiz__option.is-wrong {
  border-color: #ef4444;
  background: #fef2f2;
  cursor: default;
  transform: none;
}
.part-quiz__option[disabled] { cursor: default; }

.part-quiz__opt-label {
  flex-shrink: 0;
  font-size: 11px;
  font-weight: 700;
  color: var(--color-text-muted);
  width: 20px;
  margin-top: 1px;
  transition: color 0.18s;
}
.part-quiz__option.is-selected .part-quiz__opt-label { color: var(--color-primary); }
.part-quiz__option.is-correct .part-quiz__opt-label { color: var(--color-primary); }
.part-quiz__option.is-wrong .part-quiz__opt-label { color: #ef4444; }

.part-quiz__opt-text {
  font-size: 14px;
  line-height: 1.5;
  font-weight: 500;
}

/* Footer */
.part-quiz__footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 12px;
  padding-top: 16px;
  border-top: 1px solid var(--color-border);
}

.part-quiz__answered-count {
  font-size: 12px;
  color: var(--color-text-muted);
}

.part-quiz__submit {
  background: var(--color-primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-md);
  padding: 12px 28px;
  font-size: 14px;
  font-weight: 700;
  font-family: var(--font-sans);
  cursor: pointer;
  transition: background 0.2s, opacity 0.2s, transform 0.15s;
}
.part-quiz__submit:hover:not([disabled]) {
  background: var(--color-primary-dark);
  transform: translateY(-1px);
}
.part-quiz__submit[disabled] {
  opacity: 0.3;
  cursor: not-allowed;
  transform: none;
}

/* ===========================
   Result Panel
=========================== */
.part-quiz__result {
  background: #fff;
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: 36px 32px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 24px;
  text-align: center;
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.4s ease, transform 0.4s ease;
}
.part-quiz__result.is-visible {
  opacity: 1;
  transform: none;
}
.part-quiz__result[hidden] { display: none; }

/* Score */
.part-quiz__score-label {
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--color-text-muted);
  margin-bottom: 4px;
}
.part-quiz__score-value {
  font-size: 56px;
  font-weight: 800;
  letter-spacing: -0.04em;
  line-height: 1;
  color: var(--color-text);
}
.part-quiz__score-value.is-perfect { color: var(--color-primary); }
.part-quiz__score-denom {
  font-size: 0.4em;
  color: var(--color-text-muted);
  font-weight: 700;
}

/* Result message */
.part-quiz__result-msg {
  font-size: 15px;
  font-weight: 700;
  color: var(--color-text);
  line-height: 1.5;
  max-width: 380px;
}

/* Breakdown icons */
.part-quiz__breakdown {
  display: flex;
  gap: 12px;
  justify-content: center;
}
.part-quiz__breakdown-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 5px;
}
.part-quiz__breakdown-q {
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.12em;
  color: var(--color-text-muted);
  text-transform: uppercase;
}
.part-quiz__breakdown-icon {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}
.part-quiz__breakdown-icon--correct {
  background: var(--color-primary-bg);
  border: 1.5px solid var(--color-primary);
  color: var(--color-primary);
}
.part-quiz__breakdown-icon--wrong {
  background: #fef2f2;
  border: 1.5px solid #ef4444;
  color: #ef4444;
}

/* Explanations */
.part-quiz__explanations {
  width: 100%;
  max-width: 520px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  text-align: left;
}
.part-quiz__explanation {
  padding: 12px 16px;
  border-left: 3px solid var(--color-border);
  background: #fafafa;
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
  font-size: 13px;
  line-height: 1.7;
  color: var(--color-text-muted);
}
.part-quiz__explanation.is-correct { border-left-color: var(--color-primary); }
.part-quiz__explanation.is-wrong { border-left-color: #ef4444; }
.part-quiz__explanation strong {
  display: block;
  font-size: 10px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  margin-bottom: 4px;
  font-weight: 700;
}
.part-quiz__explanation.is-correct strong { color: var(--color-primary); }
.part-quiz__explanation.is-wrong strong { color: #ef4444; }

/* Action buttons */
.part-quiz__actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  justify-content: center;
}
.part-quiz__next-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 13px 28px;
  background: var(--color-primary);
  color: #fff;
  border: none;
  border-radius: var(--radius-md);
  font-size: 14px;
  font-weight: 700;
  font-family: var(--font-sans);
  cursor: pointer;
  text-decoration: none;
  transition: background 0.2s, transform 0.15s;
}
.part-quiz__next-btn:hover {
  background: var(--color-primary-dark);
  transform: translateY(-1px);
}
.part-quiz__retry-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 22px;
  background: #fff;
  color: var(--color-text-muted);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  font-size: 13px;
  font-weight: 600;
  font-family: var(--font-sans);
  cursor: pointer;
  transition: border-color 0.2s, color 0.2s;
}
.part-quiz__retry-btn:hover {
  border-color: var(--color-text-muted);
  color: var(--color-text);
}