:root {
  color-scheme: light only;
  --ink: #1E293B;
  --ink-soft: #64748B;
  --bg: #FAFAF9;
  --card: #FFFFFF;
  --border: #E7E5E4;
  --accent: #4F46E5;
  --accent-soft: #EEF2FF;
  --good: #10B981;
  --good-soft: #ECFDF5;
  --bad: #F43F5E;
  --bad-soft: #FFF1F2;
  --radius: 16px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

#app {
  max-width: 480px;
  margin: 0 auto;
  min-height: 100vh;
  padding-bottom: 32px;
}

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 20px 12px;
}

.topbar-title {
  font-size: 19px;
  font-weight: 700;
}

.streak-badge {
  font-size: 14px;
  font-weight: 600;
  background: var(--accent-soft);
  color: var(--accent);
  padding: 6px 12px;
  border-radius: 999px;
}

.view {
  padding: 0 20px;
}

.home-intro {
  color: var(--ink-soft);
  font-size: 14px;
  margin: 0 0 16px;
}

.stat-row {
  display: flex;
  gap: 12px;
  margin-bottom: 20px;
}

.stat-card {
  flex: 1;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 16px;
  text-align: center;
}

.stat-number {
  font-size: 24px;
  font-weight: 700;
  color: var(--accent);
}

.stat-label {
  font-size: 12px;
  color: var(--ink-soft);
  margin-top: 2px;
}

.checklist {
  display: flex;
  flex-direction: column;
  gap: 10px;
  margin-bottom: 24px;
}

.check-item {
  display: flex;
  align-items: center;
  gap: 12px;
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  text-align: left;
  cursor: pointer;
  font: inherit;
  color: inherit;
  width: 100%;
}

.check-icon { font-size: 22px; }

.check-text {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.check-title { font-weight: 600; font-size: 15px; }
.check-sub { font-size: 12px; color: var(--ink-soft); }

.check-mark {
  opacity: 0;
  color: var(--good);
  font-size: 18px;
  font-weight: 700;
}

.check-item.done {
  border-color: var(--good);
  background: var(--good-soft);
}
.check-item.done .check-mark { opacity: 1; }

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

.btn {
  border: none;
  border-radius: 12px;
  padding: 14px 16px;
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
  font-family: inherit;
}

.btn-primary { background: var(--accent); color: #fff; }
.btn-secondary { background: var(--accent-soft); color: var(--accent); }
.btn-outline { background: var(--card); color: var(--ink); border: 1px solid var(--border); }
.btn-outline-good { background: var(--good-soft); color: var(--good); flex: 1; }
.btn-outline-bad { background: var(--bad-soft); color: var(--bad); flex: 1; }
.btn-full { width: 100%; margin: 16px 0; }

.extra-title { margin-top: 8px; }

.section-title.small { font-size: 15px; margin-bottom: 12px; }

.quiz-question {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 14px 16px;
  margin-bottom: 10px;
}

.quiz-question-title { font-weight: 600; font-size: 14px; margin-bottom: 8px; }

.quiz-options {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.quiz-option {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  padding: 6px 4px;
  cursor: pointer;
}

.gap {
  display: inline-block;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 700;
  border-radius: 6px;
  padding: 0 4px;
}

.btn-back {
  background: none;
  border: none;
  color: var(--ink-soft);
  font-size: 14px;
  padding: 20px 0 8px;
  cursor: pointer;
  font-family: inherit;
}

.section-title {
  font-size: 18px;
  font-weight: 700;
  margin-bottom: 4px;
}

.section-hint {
  font-size: 13px;
  color: var(--ink-soft);
  margin: 4px 0 16px;
}

.vocab-progress {
  font-size: 13px;
  color: var(--ink-soft);
  margin-bottom: 12px;
}

.flash-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 40px 24px;
  min-height: 200px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: 10px;
  cursor: pointer;
}

.flash-word { font-size: 26px; font-weight: 700; }
.flash-word.small { font-size: 20px; color: var(--accent); }
.flash-hint { font-size: 12px; color: var(--ink-soft); margin-top: 8px; }
.flash-meaning { font-size: 16px; font-weight: 600; }
.flash-example { font-size: 14px; color: var(--ink-soft); font-style: italic; }

.vocab-actions {
  display: flex;
  gap: 10px;
  margin-top: 16px;
}

.shadow-card, .prompt-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  font-size: 17px;
  font-weight: 500;
  line-height: 1.5;
  margin-bottom: 16px;
}

.stack-actions {
  display: flex;
  gap: 10px;
  margin-bottom: 16px;
}
.stack-actions .btn { flex: 1; }

.transcript-box {
  background: var(--accent-soft);
  border-radius: 12px;
  padding: 14px 16px;
  min-height: 60px;
  font-size: 14px;
  color: var(--ink);
  margin-bottom: 8px;
}

.write-textarea {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 14px 16px;
  font-size: 15px;
  font-family: inherit;
  resize: vertical;
  margin-top: 4px;
}

.feedback-box {
  margin-top: 8px;
}

.feedback-loading, .feedback-error {
  text-align: center;
  color: var(--ink-soft);
  font-size: 14px;
  padding: 16px;
}

.feedback-praise {
  background: var(--good-soft);
  color: #065F46;
  border-radius: 12px;
  padding: 14px 16px;
  font-size: 14px;
  font-weight: 600;
  margin-bottom: 16px;
}

.feedback-section-title {
  font-size: 13px;
  font-weight: 700;
  color: var(--ink-soft);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  margin: 16px 0 8px;
}

.correction {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px 14px;
  margin-bottom: 8px;
}

.correction-original { font-size: 14px; color: var(--bad); text-decoration: line-through; }
.correction-arrow { color: var(--ink-soft); font-size: 12px; margin: 4px 0; }
.correction-improved { font-size: 14px; color: var(--good); font-weight: 600; }
.correction-reason { font-size: 13px; color: var(--ink-soft); margin-top: 6px; }

.natural-rewrite {
  background: var(--accent-soft);
  border-radius: 12px;
  padding: 14px 16px;
  font-size: 14px;
  font-style: italic;
}

.new-word {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px 14px;
  margin-bottom: 8px;
}

.new-word-title { font-weight: 700; font-size: 14px; }
.new-word-meaning { font-weight: 400; color: var(--ink-soft); font-size: 13px; }
.new-word-example { font-size: 13px; color: var(--ink-soft); font-style: italic; margin: 4px 0 8px; }

.btn-add-word {
  background: var(--accent-soft);
  color: var(--accent);
  border: none;
  border-radius: 8px;
  padding: 6px 12px;
  font-size: 12px;
  font-weight: 600;
  cursor: pointer;
  font-family: inherit;
}
.btn-add-word:disabled { opacity: 0.6; cursor: default; }