#videoDiv2 {width:100%; max-width:100%; margin:auto; display:block; position: relative;} /* This has been changed */
#video2{width:100%; height:auto } /* This has been changed */
#videoMessage2 { position: absolute; top: 0; left: 0;
display: flex;
flex-direction: column; 
justify-content: center;
align-items: center; 
width: 100%;
height: 100%;}