#acf-flashcards {
  max-width: 500px;
  margin: auto;
}
.acf-selector {
  text-align: center;
  margin-bottom: 15px;
}
.acf-selector label {
  margin-right: 5px;
  font-size: 1.1em;
}
#acf-timer {
  text-align: center;
  font-size: 1.2em;
  margin-bottom: 15px;
}
.acf-card-front, .acf-card-back {
  font-family: 'Arial', 'Tahoma', sans-serif;
  font-size: 2em;
  text-align: center;
  margin: 0 auto 20px;
  width: 80%;
  border: 2px solid #ddd;
  padding: 20px;
  border-radius: 10px;
}
.acf-controls {
  text-align: center;
}
.acf-controls button {
  margin: 0 10px;
  padding: 10px 20px;
  font-size: 1em;
}
#acf-score {
  text-align: center;
  font-size: 1.2em;
  margin-top: 15px;
}

/* ── Lock overlay (v2) ─────────────────────────────── */
#acf-lock-overlay {
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
  margin-top: 16px;
}
.acf-lock-box {
  background: #fff;
  border: 2px solid #fde68a;
  border-radius: 16px;
  padding: 32px 28px;
  text-align: center;
  max-width: 420px;
  width: 100%;
  box-shadow: 0 4px 24px rgba(0,0,0,.08);
}
.acf-lock-icon  { font-size: 40px; margin-bottom: 10px; }
.acf-lock-title { font-size: 18px; font-weight: 700; color: #1e3a5f; margin: 0 0 8px; }
.acf-lock-sub   { font-size: 14px; color: #64748b; margin: 0 0 18px; }
.acf-buy-btn {
  display: inline-block;
  background: #e91e8c;
  color: #fff;
  padding: 11px 26px;
  border-radius: 999px;
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: background .18s;
}
.acf-buy-btn:hover { background: #c4187a; color: #fff; }
.acf-lock-note {
  font-size: 12px;
  color: #94a3b8;
  margin: 12px 0 0;
}
/* Lock badge on option */
#acf-level option[data-locked="1"] { color: #888; }