image size class bootstrap code example
Example 1: how to make image responsive bootstrap 4
<img src="..." class="img-fluid" alt="Responsive image">
Example 2: image responsive bootstrap 4
<img class="img-fluid" src="" alt=""> //This will make your image responsive
Example 3: bootstrap image size
.top1 {
height:390px;
background-color:#FFFFFF;
margin-top:10px;
overflow: hidden;
}
.top1 img {
height:100%;
}