s" />
        <meta name="flags" content="ahem" />
        <meta name="assert" content="The 'margin-top' property sets a nominal length value in 'em' units." />
        <style type="text/css">* { margin: 0; padding: 0 }
            div
            {
                font: 20px/1 Ahem;
                height: 0;
            }
            #div1
            {
                border-top: 1em solid red;
                margin-bottom: -7em;
            }
            #div2
            {
            