:root {
  --color-bg: #f4f5f7;
  --color-panel: #ffffff;
  --color-border: #e0e2e7;
  --color-text: #1f2328;
  --color-muted: #6b7280;
  --color-primary: #2563eb;
  --color-primary-hover: #1d4ed8;
  --color-correct: #16a34a;
  --color-correct-bg: #eafaf0;
  --color-incorrect: #dc2626;
  --color-incorrect-bg: #fdecec;
  --color-dark: #111827;
  --color-dark-hover: #000000;
  --radius: 10px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "Segoe UI", "Hiragino Kaku Gothic ProN", "Yu Gothic", sans-serif;
  background: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
}

.app-shell {
  max-width: 800px;
  margin: 0 auto;
  padding: 24px 20px 80px;
}

.view.hidden {
  display: none;
}

.page-header {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 20px;
}

.page-header h1 {
  font-size: 1.4rem;
  margin: 0;
  flex: 1;
}

.progress-badge {
  font-size: 0.9rem;
  color: var(--color-muted);
  white-space: nowrap;
}

.panel {
  background: var(--color-panel);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px;
  margin-bottom: 20px;
}

.panel h2 {
  margin-top: 0;
  font-size: 1.05rem;
  display: flex;
  align-items: center;
  gap: 8px;
}

.icon-heading {
  color: var(--color-primary);
  flex-shrink: 0;
}

.muted {
  color: var(--color-muted);
}

.hidden {
  display: none !important;
}

/* ボタン */
.btn {
  font-size: 0.95rem;
  padding: 9px 16px;
  border-radius: 8px;
  border: 1px solid transparent;
  cursor: pointer;
  background: none;
}
.btn:disabled {
  opacity: 0.45;
  cursor: not-allowed;
}

.btn-primary {
  background: var(--color-primary);
  color: #fff;
}
.btn-primary:hover:not(:disabled) {
  background: var(--color-primary-hover);
}
.btn-primary:disabled {
  background: #b7c6f2;
  cursor: not-allowed;
}

.btn-secondary {
  background: #fff;
  border-color: var(--color-border);
  color: var(--color-text);
}
.btn-secondary:hover:not(:disabled) {
  background: #f0f1f3;
}

/* 回答する（シャッフル）: 白背景のままだが、回答する系のボタンであることが伝わるよう枠を青くする */
.btn-answer-outline {
  border-width: 2px;
  border-color: var(--color-primary);
  color: var(--color-primary);
}
.btn-answer-outline:hover:not(:disabled) {
  background: #f5f8ff;
}

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

.btn-success {
  background: var(--color-correct);
  color: #fff;
}
.btn-success:hover:not(:disabled) {
  background: #128a3e;
}

/* 青は「回答する」系のボタン専用。ナビゲーション系はこちらを使う */
.btn-dark {
  background: var(--color-dark);
  color: #fff;
}
.btn-dark:hover:not(:disabled) {
  background: var(--color-dark-hover);
}

.btn-fixed {
  min-width: 140px;
  text-align: center;
}

.btn-link {
  color: var(--color-primary);
  padding: 4px 6px;
}
.btn-link:hover {
  text-decoration: underline;
}

.btn-toggle {
  background: #fff;
  border-color: var(--color-border);
  color: var(--color-muted);
  border-radius: 999px;
  padding: 4px 12px;
  font-size: 0.78rem;
  font-weight: 400;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease;
}
.btn-toggle:hover:not(.active):not(:disabled) {
  border-color: var(--color-dark);
  color: var(--color-dark);
  background: #f2f2f3;
}
.btn-toggle.active {
  background: var(--color-dark);
  border-color: var(--color-dark);
  color: #fff;
  font-weight: 400;
}

/* インポート */
.add-set-row {
  margin-top: 14px;
  text-align: center;
}
.btn-small {
  font-size: 0.82rem;
  padding: 6px 12px;
  color: var(--color-muted);
}
.error-text {
  color: var(--color-incorrect);
  margin-top: 12px;
  margin-bottom: 0;
}

/* セット一覧（回答一覧: 横幅いっぱいのカード） */
.sets-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.set-card {
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 14px 16px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.set-card-title {
  font-weight: 600;
}
.set-card-desc {
  color: var(--color-muted);
  font-size: 0.85rem;
  margin-top: 2px;
  cursor: help;
}
.set-card-meta {
  margin-top: 6px;
  display: flex;
  gap: 8px;
  align-items: center;
  flex-wrap: wrap;
  font-size: 0.85rem;
  color: var(--color-muted);
}

/* カルーセルカード内の1行分のバッジ列（examination+問題数、シラバス+バージョンなど） */
.set-card-meta-row {
  display: flex;
  gap: 8px;
  align-items: center;
  flex-wrap: wrap;
  font-size: 0.85rem;
  color: var(--color-muted);
}

.set-card-actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

/* 問題セット一覧（カルーセル） */
.sets-carousel {
  display: flex;
  align-items: stretch;
  gap: 14px;
  overflow-x: auto;
  overflow-y: hidden;
  /* スクロールバーが出ない場合でもその分の高さをあらかじめ確保しておき、
     出現時に全体の高さがガタつかないようにする（常時表示はしない） */
  min-height: 300px;
  padding-bottom: 10px;
  scroll-snap-type: x proximity;
  -webkit-overflow-scrolling: touch;
}

.set-card-carousel {
  flex: 0 0 260px;
  scroll-snap-align: start;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 14px 16px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  background: var(--color-panel);
}

.set-card-carousel .set-card-desc {
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* タイトルの行数がカードごとに1行/2行とバラつくと、その下のバッジ・ボタンの縦位置が
   カード間でズレてしまうため、実際の行数に関わらず常に2行分の高さを確保する。 */
.set-card-carousel .set-card-title {
  line-height: 1.3;
  min-height: calc(1.3em * 2);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.set-card-carousel .set-card-actions {
  flex-direction: column;
}
.set-card-carousel .set-card-actions .btn {
  width: 100%;
}

.badge {
  border-radius: 999px;
  padding: 2px 10px;
  font-size: 0.78rem;
  font-weight: 600;
}
.badge-not_started {
  background: #eceff1;
  color: #546e7a;
}
.badge-in_progress {
  background: #fff4d6;
  color: #a06400;
}
.badge-completed {
  background: var(--color-correct-bg);
  color: var(--color-correct);
}
.badge-examination {
  background: #eafaf0;
  color: var(--color-correct);
}
.badge-syllabus {
  background: #e8eefc;
  color: var(--color-primary);
}
.badge-version {
  background: #f1eefc;
  color: #7c3aed;
}
.badge-count {
  background: #eceff1;
  color: #546e7a;
}

/* 画面共通: アイコン付きタイトル */
.title-row {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* 出題画面 */
.icon-grid {
  fill: currentColor;
  margin-right: 4px;
  vertical-align: -2px;
}
.icon-chevron {
  vertical-align: -1px;
}
.btn .icon-chevron:first-child {
  margin-right: 4px;
}
.btn .icon-chevron:last-child {
  margin-left: 4px;
}

/* 出題・見直し共通 */
.question-text {
  font-size: 0.92rem;
  font-weight: 400;
  margin-top: 0;
  white-space: pre-wrap;
}

.choices-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-top: 16px;
}

.choice-card {
  width: 100%;
  text-align: left;
  border: 1px solid transparent;
  border-radius: var(--radius);
  padding: 14px 16px;
  background: #f3f4f6;
  cursor: pointer;
  font: inherit;
  color: inherit;
}
.choice-card:hover:not(:disabled) {
  background: #ebedf1;
}
.choice-card:disabled {
  cursor: default;
}
.choice-static {
  cursor: default;
}

.choice-head {
  display: flex;
  align-items: center;
  gap: 10px;
}
.choice-label {
  font-weight: 700;
  color: var(--color-muted);
  flex-shrink: 0;
}
.choice-radio {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  border: 2px solid var(--color-border);
  flex-shrink: 0;
  box-sizing: border-box;
  position: relative;
  transition: border-color 0.15s ease;
}
.choice-card:hover:not(:disabled) .choice-radio {
  border-color: var(--color-primary);
}
.choice-radio.choice-radio-checked {
  border-color: currentColor;
}
.choice-radio.choice-radio-checked::after {
  content: '';
  position: absolute;
  inset: 3px;
  border-radius: 50%;
  background: currentColor;
}
.choice-correct .choice-radio-checked {
  color: var(--color-correct);
}
.choice-incorrect .choice-radio-checked {
  color: var(--color-incorrect);
}
.choice-text {
  flex: 1;
  min-width: 0;
  font-weight: 600;
  font-size: 0.88rem;
}
.choice-mark {
  margin-top: 6px;
  font-size: 0.88rem;
  font-weight: 700;
}
.mark-correct {
  color: var(--color-correct);
}
.mark-incorrect {
  color: var(--color-incorrect);
}

.choice-desc {
  margin-top: 6px;
  color: var(--color-muted);
  font-size: 0.9rem;
  white-space: pre-wrap;
}

.choice-correct {
  background: var(--color-correct-bg);
}
.choice-incorrect {
  background: var(--color-incorrect-bg);
}

.feedback {
  margin-top: 16px;
  padding: 10px 14px;
  border-radius: 8px;
  font-weight: 600;
}
.feedback-neutral {
  background: #f0f1f3;
  color: var(--color-muted);
  font-weight: 500;
}

.nav-row {
  display: flex;
  justify-content: space-between;
  gap: 10px;
}

/* 出題画面・見直し画面のnav-row共通: 中央に問題番号を挟む3カラムのグリッドにする */
.nav-row-grid {
  display: grid;
  grid-template-columns: auto 1fr auto;
  grid-template-areas: "left progress next";
  align-items: center;
}
.nav-row-grid .nav-row-left {
  grid-area: left;
  display: flex;
  gap: 10px;
}
.nav-row-grid .nav-row-progress {
  grid-area: progress;
  text-align: center;
}
.nav-row-grid .nav-row-next {
  grid-area: next;
}

/* モーダル共通 */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(15, 23, 42, 0.45);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 1000;
}
.modal-overlay.hidden {
  display: none;
}
.modal-panel {
  background: var(--color-panel);
  border-radius: var(--radius);
  padding: 24px;
  width: 100%;
  max-width: 640px;
  max-height: 82vh;
  overflow-y: auto;
}
.modal-panel h2 {
  margin-top: 0;
  font-size: 0.95rem;
}
.modal-panel-narrow {
  max-width: 400px;
}
.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  margin-top: 20px;
}

/* アクセスキー入力モーダル */
.key-modal-desc {
  font-size: 0.85rem;
}
.key-input {
  width: 100%;
  box-sizing: border-box;
  padding: 10px 12px;
  margin-top: 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-small, 8px);
  font-size: 0.95rem;
}
.key-input:focus {
  outline: 2px solid var(--color-primary);
  outline-offset: 1px;
}
.key-modal-purchase-row {
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--color-border);
}
.key-modal-purchase-link {
  display: block;
  width: 100%;
  box-sizing: border-box;
  text-align: center;
  text-decoration: none;
  color: #fff;
}
.key-modal-purchase-link:hover {
  color: #fff;
}

/* 問題一覧モーダル */
.quiz-index-legend {
  display: flex;
  gap: 18px;
  align-items: center;
  margin-bottom: 16px;
  font-size: 0.85rem;
  color: var(--color-muted);
}
.legend-item {
  display: flex;
  align-items: center;
  gap: 6px;
}
.legend-swatch {
  width: 18px;
  height: 18px;
  border-radius: 4px;
  border: 2px solid var(--color-border);
  background: #fff;
  display: inline-block;
}
.legend-swatch-answered {
  background: var(--color-primary);
  border-color: var(--color-primary);
}
.quiz-index-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(38px, 1fr));
  gap: 8px;
}
.quiz-index-chip {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  height: 38px;
  border-radius: 8px;
  border: 2px solid var(--color-border);
  background: #fff;
  color: var(--color-text);
  font-weight: 700;
  font-size: 0.85rem;
  cursor: pointer;
}
.quiz-index-chip:hover {
  border-color: var(--color-primary);
}
.quiz-index-chip.answered {
  background: var(--color-primary);
  border-color: var(--color-primary);
  color: #fff;
}
.quiz-index-chip.current {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}

/* 結果画面 */
.result-panel {
  text-align: center;
}
.result-summary {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 32px;
  flex-wrap: wrap;
  margin: 20px 0;
}
.result-donut {
  position: relative;
  width: 140px;
  height: 140px;
  border-radius: 50%;
  flex-shrink: 0;
}
.result-donut-center {
  position: absolute;
  inset: 18px;
  border-radius: 50%;
  background: var(--color-panel);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}
.result-donut-fraction {
  font-size: 1.5rem;
  font-weight: 700;
}
.result-donut-percent {
  font-size: 0.9rem;
  color: var(--color-muted);
}
.result-breakdown-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  text-align: left;
}
.result-breakdown-row {
  display: flex;
  align-items: baseline;
  gap: 24px;
  min-width: 140px;
  justify-content: space-between;
  font-size: 0.95rem;
  color: var(--color-muted);
}
.result-breakdown-row strong {
  font-size: 1.15rem;
  color: var(--color-text);
}
.result-count-correct {
  color: var(--color-correct) !important;
}
.result-count-incorrect {
  color: var(--color-incorrect) !important;
}
.result-review-hint {
  font-size: 0.85rem;
}
.result-actions {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
  margin-top: 8px;
}

/* 見直し画面 */
.review-score {
  margin-bottom: 12px;
}
.review-score-main {
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--color-primary);
}
.review-score-percent {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-muted);
  margin-left: 6px;
}

.filter-row {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 14px;
  flex-wrap: wrap;
}

/* 問題一覧モーダルの問題番号グリッドと同じ見た目・レイアウトに揃える */
.index-nav {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(38px, 1fr));
  gap: 8px;
  margin-bottom: 16px;
}
.index-chip {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  height: 38px;
  border-radius: 8px;
  border: 2px solid var(--color-border);
  background: #fff;
  color: var(--color-text);
  font-weight: 700;
  cursor: pointer;
  font-size: 0.85rem;
}
.index-chip.chip-correct {
  border-color: var(--color-correct);
  color: var(--color-correct);
}
.index-chip.chip-incorrect {
  border-color: var(--color-incorrect);
  color: var(--color-incorrect);
}
.index-chip.chip-unanswered {
  color: var(--color-muted);
}
.index-chip.active {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}

/* スマホ縦持ち対応 */
@media (max-width: 640px) {
  .app-shell {
    padding: 16px 14px 60px;
  }

  .page-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 6px;
  }
  .page-header h1 {
    width: 100%;
    font-size: 1.2rem;
  }
  #quiz-interrupt-btn {
    align-self: flex-end;
  }

  .panel {
    padding: 16px;
  }

  .btn {
    padding: 12px 16px;
    font-size: 1rem;
  }
  .btn-small {
    padding: 10px 14px;
  }
  /* フィルターボタンは通常のbtnより小さいまま保つ（上のルールで上書きされないようにする） */
  .btn-toggle {
    padding: 4px 12px;
    font-size: 0.78rem;
  }

  .set-card {
    flex-direction: column;
    align-items: stretch;
  }
  .set-card-actions {
    flex-direction: column;
  }
  .set-card-actions .btn {
    width: 100%;
  }

  /* 出題・見直し画面の下部ナビは、内容の長さに関わらず常に画面下部に固定する
     （sticky だと解説文の有無で「浮く/浮かない」がぶれてボタン位置が毎回ずれるため fixed に統一） */
  .nav-row {
    gap: 10px;
    flex-wrap: wrap;
    position: fixed;
    left: 0;
    right: 0;
    bottom: 0;
    margin: 0 auto;
    max-width: 800px;
    background: var(--color-bg);
    padding: 8px 14px calc(8px + env(safe-area-inset-bottom, 0px));
    box-shadow: 0 -6px 10px -6px rgba(0, 0, 0, 0.15);
    z-index: 5;
  }
  .nav-row-left .btn {
    flex: 1;
  }
  .nav-row-grid {
    grid-template-columns: 2fr 1fr;
    grid-template-areas:
      "left next"
      "progress progress";
    row-gap: 10px;
  }

  /* 固定ナビの高さぶん、最後の内容が隠れないよう余白を確保する */
  #view-quiz .panel,
  #view-review .panel {
    margin-bottom: 92px;
  }

  .result-actions {
    flex-direction: column;
    align-items: stretch;
  }

  .filter-row {
    justify-content: flex-start;
  }

  /* 問題一覧モーダル・見直し画面の問題番号ボックスは、スマホでは一回り小さくして収まりやすくする */
  .quiz-index-grid,
  .index-nav {
    grid-template-columns: repeat(auto-fill, minmax(30px, 1fr));
    gap: 6px;
  }
  .quiz-index-chip,
  .index-chip {
    height: 30px;
    font-size: 0.75rem;
  }
}