html {
    background: #000;
}

div.img {
    width: 200px;
    height: 200px;
    margin: 25px;
    text-align: center;
    float: left;
    background-image: url("slate.png");
    background-size: cover;
}

div.img img {
   max-height: 150px;
   max-width: 150px;
   margin: 20px;
   position: relative;
   top: 78px;
   transform: translateY(-50%);
   clear: both;
   filter:invert(0.9); 
}

div.img a.img {
    text-decoration: none; 
    clear: both; 
}

div.img a.button {
    width: 100%;
    text-decoration: none;
    background-color: #000;
    color: #fff;
    padding: 10px;
    border-radius: 10px;
}