body {
  padding: 0;
  margin: 0;
  overflow:hidden;
}

div {
  width: 100vw;
  height: 100vh;
  background-image: url(../img/photo.jpg);
  background-size: cover;
  background-position: center center;
}

canvas {
  width: 100vw;
  height: 100vh;
  mix-blend-mode: overlay;
}