:root {
  --bg: #f4f6f8;
  --card: #ffffff;
  --ink: #1c2530;
  --muted: #6b7783;
  --line: #e3e8ee;
  --primary: #2b6cb0;
  --primary-ink: #ffffff;
  --correct: #2f855a;
  --correct-bg: #e6f4ea;
  --wrong: #c53030;
  --wrong-bg: #fbeaea;
  --gold: #b7791f;
  --radius: 14px;
}

* { box-sizing: border-box; -webkit-tap-highlight-color: transparent; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Kaku Gothic ProN",
    "Noto Sans JP", "Yu Gothic", Meiryo, sans-serif;
  line-height: 1.7;
}

#app {
  max-width: 560px;
  margin: 0 auto;
  padding: 16px 16px 48px;
}

.screen { animation: fade .18s ease; }
@keyframes fade { from { opacity: 0; transform: translateY(4px); } to { opacity: 1; transform: none; } }

.app-header {
  display: flex; align-items: center; justify-content: space-between;
  gap: 12px; margin: 8px 0 16px;
}
.app-header h1 { font-size: 1.15rem; margin: 0; }
.streak {
  font-size: .8rem; font-weight: 700; color: var(--gold);
  background: #fff7e6; border: 1px solid #f0e0b8;
  padding: 4px 10px; border-radius: 999px; white-space: nowrap;
}

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  margin-bottom: 16px;
}

.summary-row { display: flex; }
.summary-item { flex: 1; text-align: center; }
.summary-item + .summary-item { border-left: 1px solid var(--line); }
.summary-num { font-size: 1.5rem; font-weight: 800; }
.summary-label { font-size: .72rem; color: var(--muted); }

.section-title { font-size: .9rem; color: var(--muted); margin: 22px 4px 10px; }

.btn {
  display: block; width: 100%;
  border: none; border-radius: var(--radius);
  padding: 14px 16px; font-size: 1rem; font-weight: 700;
  cursor: pointer; font-family: inherit;
  transition: transform .05s ease, opacity .15s ease;
}
.btn:active { transform: scale(.99); }
.btn-primary { background: var(--primary); color: var(--primary-ink); }
.btn-big { padding: 16px; }
.btn-sub { display: block; font-size: .74rem; font-weight: 500; opacity: .85; margin-top: 2px; }

/* 歴史の流れ（時系列）モード */
.notice { background: #fff7e6; border: 1px solid #f0e0b8; color: #8a6d1f; font-size: .85rem; font-weight: 700; padding: 10px 12px; border-radius: 10px; margin: 0 0 14px; }
.notice.ok { background: var(--correct-bg); border-color: #bfe3cc; color: var(--correct); }

.btn-flow { background: #3a4a63; color: #fff; margin-top: 12px; }
.flow-restart-line { text-align: center; margin: 6px 0 0; }
.result-flow { font-size: .86rem; color: var(--muted); margin: 12px 0 0; font-weight: 700; }
#btn-flow-continue { margin-bottom: 10px; }
.q-year { font-size: .72rem; padding: 2px 8px; border-radius: 999px; background: #eef2f7; color: #3a4a63; font-weight: 700; }

.unit-btn {
  display: flex; align-items: center; justify-content: space-between;
  width: 100%; text-align: left;
  background: var(--card); border: 1px solid var(--line);
  border-radius: var(--radius); padding: 14px 16px; margin-bottom: 10px;
  cursor: pointer; font-family: inherit; font-size: .98rem; color: var(--ink);
}
.unit-btn:active { transform: scale(.995); }
.unit-btn .unit-name { font-weight: 700; }
.unit-btn .unit-stat { font-size: .8rem; color: var(--muted); text-align: right; white-space: nowrap; }
.unit-btn.locked { opacity: .55; }
.acc-pill {
  display: inline-block; margin-top: 2px; padding: 1px 8px; border-radius: 999px;
  font-weight: 700; font-size: .78rem;
}
.acc-high { background: var(--correct-bg); color: var(--correct); }
.acc-mid  { background: #fef3d7; color: var(--gold); }
.acc-low  { background: var(--wrong-bg); color: var(--wrong); }
.acc-none { background: #eef1f4; color: var(--muted); }

.gate-card { border-style: dashed; text-align: center; }
.gate-text { font-size: .88rem; color: var(--muted); margin: 0 0 12px; }
.btn-unlock { background: var(--gold); color: #fff; }

.reset-line { text-align: center; margin-top: 20px; }
.linkbtn {
  background: none; border: none; color: var(--muted);
  font-size: .82rem; cursor: pointer; text-decoration: underline; font-family: inherit;
}

/* クイズ */
.quiz-top { display: flex; align-items: center; justify-content: space-between; margin: 4px 0 10px; }
.progress-text { font-size: .85rem; color: var(--muted); font-weight: 700; }
.progress-bar { height: 6px; background: var(--line); border-radius: 999px; overflow: hidden; margin-bottom: 16px; }
.progress-fill { height: 100%; background: var(--primary); width: 0; transition: width .25s ease; }

.q-meta { display: flex; gap: 8px; margin-bottom: 10px; }
.q-unit, .q-diff { font-size: .72rem; padding: 2px 8px; border-radius: 999px; background: #eef1f4; color: var(--muted); font-weight: 700; }
.q-diff.easy   { background: var(--correct-bg); color: var(--correct); }
.q-diff.normal { background: #eaf1f8; color: var(--primary); }
.q-diff.hard   { background: var(--wrong-bg); color: var(--wrong); }
.q-type { font-size: .72rem; padding: 2px 8px; border-radius: 999px; font-weight: 700; background: #efe6fb; color: #6b46c1; }
.q-text { font-size: 1.08rem; font-weight: 700; margin: 0 0 16px; }

.choice {
  display: block; width: 100%; text-align: left;
  background: var(--card); border: 1.5px solid var(--line);
  border-radius: 12px; padding: 13px 14px; margin-bottom: 10px;
  font-size: .98rem; cursor: pointer; font-family: inherit; color: var(--ink);
  transition: border-color .12s ease, background .12s ease;
}
.choice:active { transform: scale(.995); }
.choice:hover { border-color: #c6d2de; }
.choice.correct { border-color: var(--correct); background: var(--correct-bg); }
.choice.wrong   { border-color: var(--wrong); background: var(--wrong-bg); }
.choice.dim { opacity: .5; }
.choice:disabled { cursor: default; }
.choice-mark { font-weight: 800; margin-right: 8px; }

.feedback { margin-top: 8px; }
.feedback-head { font-weight: 800; margin-bottom: 6px; }
.feedback-head.ok { color: var(--correct); }
.feedback-head.ng { color: var(--wrong); }
.feedback-why {
  background: var(--card); border: 1px solid var(--line); border-left: 4px solid var(--primary);
  border-radius: 8px; padding: 12px; font-size: .92rem; margin: 0 0 14px;
}

/* 出題設定（形式・軸） */
.setup-card { padding: 18px 16px; }
.setup-unit { font-size: 1.1rem; margin: 0 0 14px; }
.setup-label { font-size: .8rem; color: var(--muted); font-weight: 700; margin: 14px 0 8px; }
.setup-hint { font-size: .78rem; color: var(--muted); margin: 8px 2px 0; }
.seg { display: flex; gap: 8px; }
.seg-btn {
  flex: 1; border: 1.5px solid var(--line); background: var(--card); color: var(--ink);
  border-radius: 12px; padding: 10px 6px; font-family: inherit; font-size: .9rem; font-weight: 700;
  cursor: pointer; display: flex; flex-direction: column; align-items: center; gap: 2px;
}
.seg-btn:active { transform: scale(.99); }
.seg-btn.active { border-color: var(--primary); background: #eaf1f8; color: var(--primary); }
.seg-btn:disabled { opacity: .4; cursor: default; }
.seg-n { font-size: .72rem; font-weight: 700; color: var(--muted); }
.seg-btn.active .seg-n { color: var(--primary); }
.chips { display: flex; flex-wrap: wrap; gap: 8px; }
.chip {
  border: 1.5px solid var(--line); background: var(--card); color: var(--ink);
  border-radius: 999px; padding: 6px 14px; font-family: inherit; font-size: .84rem; font-weight: 700;
  cursor: pointer;
}
.chip:active { transform: scale(.98); }
.chip.active { border-color: var(--primary); background: #eaf1f8; color: var(--primary); }
#btn-setup-start { margin-top: 20px; }

/* 解説ラベル */
.explain { margin-bottom: 14px; }
.explain-label {
  display: inline-block; font-size: .72rem; font-weight: 800; color: var(--primary);
  background: #eaf1f8; padding: 2px 10px; border-radius: 999px; margin: 0 0 6px;
}
.feedback .feedback-why { margin-bottom: 0; }
.review-why-label {
  display: inline-block; font-size: .7rem; font-weight: 800; color: var(--primary);
  margin-right: 6px;
}

/* 結果 */
.result-card { text-align: center; }
.result-title { margin: 0 0 8px; }
.result-score { font-size: 1.4rem; font-weight: 800; margin-bottom: 12px; }
.result-bar { height: 10px; background: var(--line); border-radius: 999px; overflow: hidden; margin-bottom: 12px; }
.result-bar-fill { height: 100%; background: var(--correct); width: 0; transition: width .4s ease; }
.result-msg { color: var(--muted); font-size: .92rem; margin: 0; }

.review-item {
  background: var(--card); border: 1px solid var(--line); border-radius: 12px;
  padding: 12px 14px; margin-bottom: 10px;
}
.review-q { font-weight: 700; font-size: .92rem; margin: 0 0 6px; }
.review-a { font-size: .88rem; margin: 2px 0; }
.review-a.ok { color: var(--correct); }
.review-a.ng { color: var(--wrong); }
.review-why { font-size: .84rem; color: var(--muted); margin: 6px 0 0; }
.review-badge { font-size: .74rem; font-weight: 800; margin-right: 6px; }
.review-badge.ok { color: var(--correct); }
.review-badge.ng { color: var(--wrong); }

.unlock-input {
  width: 100%; padding: 12px 14px; font-size: 1rem; margin-bottom: 12px;
  border: 1.5px solid var(--line); border-radius: 12px; font-family: inherit;
}
.unlock-err { color: var(--wrong); font-size: .85rem; margin: 4px 0 0; }