.px-mask {
  width: 100%;
  height: 100%;
  position: absolute;
  border-width: 0;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
}
.px-mask-canvas {
  position: absolute;
  top: 0;
  left: 0;
  bottom: 0;
  right: 0;
}