body, html {
    margin: 0;
    padding: 0;
    width: 100%;
    height: 100%;
    overflow: hidden;
}

#myVideo {
  /* 1. Fill the viewport */
  position: fixed;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 100%;

  /* 2. Scale the video correctly */
  object-fit: cover;

  /* 3. The Alignment Magic */
  /* x-axis: center | y-axis: bottom */
  object-position: center bottom; 
  
  /* 4. Layering */
  z-index: -1;
}