body, html {width: 100%; height: 100%; 
margin: 0; 
padding: 0;
overflow-y:hidden;
background-image: url("../assets/img/classroom-back.jpg");
}

.second-row {position: absolute; top: 0px; left: 0; right: 0; bottom: 0; background-color: #33333317 ;overflow-y:hidden;}
@media all and (max-width: 500px) and (min-width: 200px) {
.second-row iframe {display: block; width: 100%; height:100%; border: none;}
}



@media all and (max-width: 3000px) and (min-width: 501px) {
.second-row iframe {
display: block;
 width: 75%; 
 height: 99%;
 margin-left:auto;
 margin-right:auto; 
 border-radius:22px; 
 border: none;
margin-top:3px;
margin-bottom:3px;
box-shadow: -2px -1px 25px 1px rgb(0 0 0 / 82%);
-webkit-box-shadow: -2px -1px 25px 1px rgb(0 0 0 / 82%);
background-image:url("../assets/img/classroom-back.jpg")
}
}