html, body {
  height: 100%;
  margin: 0;
  padding: 0;
}
body {
  width: 100vw;
  height: 100vh;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #000;
}
img.scaled-bg {
  width: 100vw;
  height: 100vh;
  object-fit: cover;
  display: block;
  max-width: 100vw;
  max-height: 100vh;
}