.Background {
background-image: url("Your picture name.jpg");
background-repeat: no-repeat;
height: 100%;
background-position: center;
background-size: cover;
}html {
background: url(images/bg.jpg) no-repeat
center center fixed;
-webkit-background-size: cover;
-moz-background-size: cover;
-o-background-size: cover;
background-size: cover;
}body {
background-position: center;
background-repeat: no-repeat;
background-size: cover;
}body {
background-position: center;
background-repeat: no-repeat;
background-size: contain;
}