/* Minimal, responsive styles */
:root{
  --bg:#f6f8fb; --card:#fff; --accent:#0066cc; --muted:#6b7280;
  font-family: Inter, system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial;
}
*{box-sizing:border-box}
body{margin:0;background:var(--bg);color:#111}
.topbar{display:flex;justify-content:space-between;align-items:center;padding:12px 16px;background:linear-gradient(90deg,#fff, #f3f7ff);box-shadow:0 1px 4px rgba(10,10,10,0.04)}
.brand{font-weight:700}
.container{max-width:980px;margin:20px auto;padding:0 16px}
.hero{background:var(--card);padding:20px;border-radius:12px;margin-bottom:16px}
.cta-row{margin-top:12px;display:flex;gap:8px}
.btn{padding:8px 12px;border-radius:8px;border:1px solid rgba(0,0,0,0.06);background:white;cursor:pointer}
.btn.primary{background:var(--accent);color:white;border:none}
.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:12px;margin-bottom:16px}
.card{background:var(--card);padding:12px;border-radius:10px;box-shadow:0 6px 18px rgba(14,30,37,0.04)}
.card h4{margin:0 0 8px 0}
.panel{background:var(--card);padding:12px;border-radius:10px;margin-bottom:16px}
.simulator{margin-top:12px}
.stats{background:var(--card);padding:12px;border-radius:10px}
.footer{text-align:center;padding:12px;color:var(--muted)}
.flashcard{border:1px dashed #ddd;padding:12px;border-radius:8px;margin-top:10px}
.hidden{display:none}
@media (max-width:600px){
  .cta-row{flex-direction:column}
}