body {
padding: 0;
margin: 0;
background: url(logo.png) no-repeat center center #111;
background-size: 150px;
height:100vh;}
.hidden {
display: none;
}
.bottom{
position: fixed;
bottom:0;
width: 100%;
    text-align: center;
    color: #FFF;
    font-family: Arial, Helvetica, sans-serif;
    font-size: 14px
}