:root {
  --bg: #f5f3ee;
  --card: #ffffff;
  --primary: #0b8a6f;
  --primary-dark: #086852;
  --text: #1f2724;
  --muted: #6b7672;
  --border: #e3ddd1;
  --maru: #2e7d32;
  --batsu: #c0392b;
  --warn: #b46a00;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic UI", "Noto Sans JP", system-ui, sans-serif;
  font-size: 16px;
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

#app {
  max-width: 720px;
  margin: 0 auto;
  padding: 16px;
  padding-bottom: env(safe-area-inset-bottom);
  min-height: 100vh;
}

.screen { display: none; }
.screen.active { display: block; }

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

header h1 {
  font-size: 28px;
  margin: 0;
  letter-spacing: 0.05em;
}

header h1 .sub {
  font-size: 18px;
  color: var(--muted);
  font-weight: 500;
}

header h2 {
  font-size: 20px;
  margin: 0;
  flex: 1;
}

.back {
  background: transparent;
  border: none;
  font-size: 15px;
  color: var(--muted);
  cursor: pointer;
  padding: 8px 0;
}

.lead {
  color: var(--muted);
  font-size: 15px;
}

.btn {
  display: block;
  width: 100%;
  padding: 16px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--card);
  color: var(--text);
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  margin-bottom: 12px;
  transition: transform 0.05s ease, background 0.15s ease;
}

.btn:active { transform: scale(0.98); }

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

.btn.primary:disabled {
  background: #c8d4cf;
  border-color: #c8d4cf;
  cursor: not-allowed;
}

.btn.ghost {
  background: transparent;
  border-color: var(--border);
}

.btn.small {
  display: inline-block;
  width: auto;
  padding: 10px 16px;
  font-size: 14px;
  margin: 4px;
}

.home-card {
  background: var(--card);
  padding: 24px;
  border-radius: 16px;
  border: 1px solid var(--border);
}

.hint {
  text-align: center;
  color: var(--muted);
  font-size: 13px;
  margin-top: 24px;
}

.filter-row {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-bottom: 16px;
  padding: 12px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
}

.filter-row label {
  font-size: 14px;
  cursor: pointer;
}

.category-list {
  display: grid;
  grid-template-columns: 1fr;
  gap: 8px;
  margin-bottom: 20px;
}

.category-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px 16px;
  cursor: pointer;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.category-card.selected {
  border-color: var(--primary);
  background: #e6f4f0;
}

.category-card .count {
  color: var(--muted);
  font-size: 13px;
}

.status-pill {
  display: inline-block;
  background: var(--card);
  border: 1px solid var(--border);
  padding: 6px 14px;
  border-radius: 999px;
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 12px;
}

.status-pill.listening {
  background: #ffe8b3;
  border-color: #f0c060;
  color: #6e4500;
}

.status-pill.speaking {
  background: #e6f4f0;
  border-color: var(--primary);
  color: var(--primary-dark);
}

.quiz-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 24px;
  min-height: 180px;
  margin-bottom: 16px;
}

.q-meta {
  font-size: 13px;
  color: var(--muted);
  margin-bottom: 8px;
}

.q-text {
  font-size: 18px;
  line-height: 1.8;
  margin: 0;
}

.progress {
  font-size: 13px;
  color: var(--muted);
}

.answer-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
  margin-bottom: 16px;
}

.btn.answer {
  font-size: 22px;
  padding: 24px;
  margin: 0;
}

.btn.answer.maru { color: var(--maru); border-color: var(--maru); }
.btn.answer.batsu { color: var(--batsu); border-color: var(--batsu); }

.btn.answer.correct {
  background: var(--maru);
  color: #fff;
}
.btn.answer.wrong {
  background: var(--batsu);
  color: #fff;
}

.result-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 20px;
  margin-bottom: 16px;
}

.result-card.hidden { display: none; }

.result-mark {
  font-size: 32px;
  font-weight: 700;
  text-align: center;
  margin-bottom: 12px;
}

.result-mark.correct { color: var(--maru); }
.result-mark.wrong { color: var(--batsu); }

.result-explain {
  font-size: 15px;
  line-height: 1.8;
  color: var(--text);
  margin: 0 0 16px;
  white-space: pre-wrap;
}

.voice-controls {
  display: flex;
  justify-content: center;
  gap: 8px;
  flex-wrap: wrap;
}

.result-summary {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 32px 24px;
  text-align: center;
  margin-bottom: 20px;
}

.big-score {
  font-size: 56px;
  font-weight: 700;
  color: var(--primary);
}

.rate {
  font-size: 18px;
  color: var(--muted);
  margin-top: 8px;
}

.wrong-summary {
  margin-top: 16px;
  font-size: 14px;
  color: var(--muted);
}

.setting-row {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px 16px;
  margin-bottom: 10px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.setting-row label {
  font-size: 14px;
  flex: 1;
}

.setting-row input[type="range"] {
  flex: 1;
  max-width: 180px;
}

.setting-row select {
  font-size: 14px;
  padding: 6px 10px;
  border: 1px solid var(--border);
  border-radius: 8px;
  max-width: 220px;
}

#history-content {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
  margin-bottom: 16px;
  font-size: 14px;
}

.error-msg {
  color: var(--batsu);
  font-size: 14px;
  margin: 8px 0 0;
  min-height: 20px;
}

#login-password {
  width: 100%;
  padding: 14px 16px;
  font-size: 16px;
  border: 1px solid var(--border);
  border-radius: 12px;
  margin-bottom: 12px;
  background: #fff;
  color: var(--text);
  -webkit-appearance: none;
}

#login-password:focus {
  outline: none;
  border-color: var(--primary);
}

.btn.small-text {
  font-size: 13px;
  font-weight: 500;
  color: var(--muted);
  padding: 10px;
  margin-top: 4px;
}

.loading-box {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 60vh;
  gap: 16px;
}

.spinner {
  width: 40px;
  height: 40px;
  border: 4px solid var(--border);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

@keyframes spin {
  to { transform: rotate(360deg); }
}

@media (max-width: 380px) {
  header h1 { font-size: 24px; }
  .q-text { font-size: 16px; }
  .btn.answer { font-size: 18px; padding: 20px; }
}