.img-shadow{
    margin-right: 50px;
    position: relative;
}

.img-shadow::before{
    content:' ';
    height: 100%;
    width:100%;
    background-color: #aaa;
    position: absolute;
    border-radius: 5%;
    border-width: 1px;
    border-style: dashed;
    border-color:#111;
}

.img-shadow::after{
    content: attr(alt);
    position: absolute;
    top:50px;
    left:50px;
}