img.bg {
/* Set rules to fill background */
min-height: 100%;
min-width: 1024px;
/* Set up proportionate scaling */
width: 100%;
height: auto;
/* Set up positioning */
position: fixed;
top: 0;
left: 0;
}
@media screen and (max-width: 1024px) { /* Specific to this particular image */
img.bg {
left: 50%;
margin-left: -512px; /* 50% */
}
}
