en-100px-square.xht">
<link rel="stylesheet" href="/css/support/grid.css">
<link rel="stylesheet" type="text/css" href="/fonts/ahem.css" />
<style>
.container {
    font: 25px/1 Ahem;
    width: 100px;
}
.child {
    margin: 50px 0px;
    color: red;
}
.ref {
    position: absolute;
    z-index: -1;
    background: green;
    height: 100px;
}
.grid {
    background: none;
}
#item {
    margin: 50% 0px;
    color: green;
}
</style>
<p>Test passes if there is a filled green square and <strong>no red</strong>.