Avoid Black Screen from displaying when loading iframe Vimeo or YouTube Video in Elementor Container Background

style.css

/* Add this CSS to the Advanced tab > Custom CSS section of the Container containing the background video 
   This solution was proposed here: https://github.com/elementor/elementor/issues/1644#issuecomment-1125174378
*/ 

selector iframe {
  opacity: 1;
  animation-name: fadeInOpacity;
  animation-iteration-count: 1;
  animation-timing-function: ease-in;
  animation-duration: 1.75s;
}

@Keyframes fadeInOpacity {
  0% {
    opacity: 0;
  }
    80% { opacity:0;
  }
  100% {
    opacity: 1;
  }
}