customized code css for video on desktop and image on mobile

Hi,

I need help! You know how to make visible a video on desktop and an image on mobile at the same time?

Few months ago they gave me this code but it doesn't work anymore:

@media only screen and (min-width: 768px) {
  section[data-section-id="6332d1ccb7f71701f90f072e"] {
    display: none;
  }
}

@media only screen and (max-width: 767px) {
  section[data-section-id="62616f21a251901291ce8981"] {
    display: none;
  }
}

Can you help me with another code please??

Thank you

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