css background full width

body {
  background-position: center;
  background-repeat: no-repeat;
  background-size: contain;
}

body { 
  background: url(img/bg-image.jpg) no-repeat center center fixed; 
  -webkit-background-size: cover;
  -moz-background-size: cover;
  -o-background-size: cover;
  background-size: cover;
}

/* One way */
background-size: cover;

/* Other option */
background-size: contain;