*{
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}


@media (max-width: 767px){

    .img-thumbnail{
        width:100%; 
    }
   
}

@media (min-width: 768px) and (max-width: 1023px){
    .img-thumbnail{
        max-width:100%; 
        height:100vh;
    }
}