html, body {
    margin: 0;
    padding: 0;
    background: #000000;
}

.responsive {
    max-width:50%;
    max-height:50%;
}
 
.center {
   position: absolute;
   top: 50%;
   left: 50%; 
   transform: translate(-50%, -50%);
}
 
logo {
   position: relative;
}