body{margin:0;background:#222;color:#fff;font-family:Arial,sans-serif} 
.game-shell{padding:10px;text-align:center} 
canvas{border:3px solid #ff0;background:#8ee;display:block;margin:0 auto} 
h1{font-size:24px;margin:8px 0;color:#ff0} 
.instructions{font-size:14px;margin-top:6px;color:#ddd}