.pfu-container { max-width: 100%; margin: auto; }
.flipbook { width: 100%; height: auto; }
.flipbook .page { background: #fff; }
.pfu-page-canvas { display: block; margin: auto; transition: transform 0.3s ease; }
.pfu-controls { text-align: center; margin-bottom: 10px; }
.pfu-controls button { margin: 0 5px; padding: 5px 10px; }
@media (max-width: 600px) {
  .flipbook { height: 300px; }
}