.vc{

      position:absolute;

      top:50%;

      left:50%;

     transform:translate(-50%,-50%);

}

.vc{

      position:absolute;

      top:50%;

      left:50%;

      width:100px;

      height:100px;

      margin:-50px 0 -50px;

}

html,body{

      position:fixed;

      width:100%;

      height:100%;

}

div{

     height:100%;

}

img{

      filter:gray;

     -webkit-filter:grayscale(1);

}

.bg{

      background-image:linear-gradient(#5187c4,#1c2f45);

      background-size:auto 200%;

      background-position:0 100%;

      transition:background-position 0.5s;

}

.bg:hover{

     background-position:0 0;

}

img.polaroid{

     background:#000;

     border:solide #fff;

     border-width:6px 6px 20px 6px;

     box-shadow:1px 1px 5px #333;

      width:200px;

     height:200px;
}