html, 
body {
  height: 100%;
}
body {
    height: 100%;
  background-color: #000;
  background: url("../images/la-rf.png") no-repeat center center fixed;
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
}
.img-responsive {
  max-width: 100%;
  height: auto;
  display:block;
}