html, 
body {
    margin: 0;
    padding: 0;
    height: 100vh; 
    overflow: hidden; 
    position: relative; 
}
    
canvas {
    display: block; 
    max-width: 100%; 
    max-height: 100vh; 
    width: auto; 
    height: auto; 
    object-fit: cover; 
    position: absolute; 
    top: 50%; 
    left: 50%; 
    transform: translate(-50%, -50%); 
}

/* FPS bar stalled animation (compositor-driven, will keep animating if main thread is busy) */
.fps-bar.fps-stalled {
  animation: fpsPulse 1s infinite ease-in-out;
}
@keyframes fpsPulse {
  0% { opacity: 1; }
  50% { opacity: 0.4; }
  100% { opacity: 1; }
}