:root {
  color-scheme: dark;
  --bg: #0f172a;
  --card-bg: #1e293b;
  --text: #f1f5f9;
  --accent: #38bdf8;
  --correct: #4ade80;
  --incorrect: #f87171;
  padding-top: env(safe-area-inset-top, 0px);
  padding-bottom: env(safe-area-inset-bottom, 0px);
}

* { box-sizing: border-box; }

body {
  margin: 0;
  padding: 16px;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  max-width: 480px;
  margin-inline: auto;
}

.app-header { text-align: center; margin-bottom: 24px; }
.app-header h1 { font-size: 1.4rem; margin: 0 0 4px; }
#streak-label { color: var(--accent); margin: 0 0 12px; }

.progress-dots { display: flex; justify-content: center; gap: 8px; }
.dot {
  width: 28px; height: 28px; border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  background: var(--card-bg); font-size: 0.85rem;
}
.dot.active { background: var(--accent); color: #0f172a; font-weight: bold; }
.dot.done { background: var(--correct); color: #0f172a; }

.block {
  background: var(--card-bg);
  border-radius: 16px;
  padding: 20px;
}

.topic-label { font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.05em; opacity: 0.7; }
.lesson-title { font-size: 1.3rem; font-weight: 700; margin: 6px 0 10px; }
.prompt { font-size: 1.1rem; line-height: 1.5; margin: 12px 0 20px; }

.options { display: flex; flex-direction: column; gap: 10px; }
.option-btn {
  padding: 14px 16px;
  border-radius: 12px;
  border: 1px solid #334155;
  background: #0f172a;
  color: var(--text);
  font-size: 1rem;
  text-align: left;
}
.option-btn.correct { border-color: var(--correct); background: #14532d; }
.option-btn.incorrect { border-color: var(--incorrect); background: #7f1d1d; }

#french-text-input {
  width: 100%; padding: 12px; border-radius: 12px; border: 1px solid #334155;
  background: #0f172a; color: var(--text); font-size: 1rem; margin-bottom: 12px;
}

button {
  padding: 12px 18px;
  border-radius: 12px;
  border: none;
  background: var(--accent);
  color: #0f172a;
  font-weight: 600;
  font-size: 1rem;
}

.feedback { margin-top: 16px; }
.explanation { line-height: 1.5; }
.source { font-size: 0.85rem; opacity: 0.75; font-style: italic; }
.next-btn { margin-top: 12px; }

.backup-actions { display: flex; flex-direction: column; gap: 10px; margin-top: 20px; }
.import-label {
  display: inline-block; text-align: center; padding: 12px 18px;
  border-radius: 12px; background: #334155; color: var(--text); font-weight: 600;
}