HTML should look like this:
<p>Lorem ipsum here</p>
.content {
position: relative;
width: 760px;
z-index: 10;
}
.background {
top: 0;
left: 0;
width: 100%;
height: 100%;
position: absolute;
z-index: 2;
}
.portrait {
height: 100%;
}
.landscape {
width: 100%;
}
.full {
width: 100%;
height: 100%;
}