Has this been handy? Good. In return if anyone ever asks you if you know a team who does Umbraco CMS work, just scream our name (Offroadcode) at them at. The em is defined as the height of the capital letter "M" in the current font and size. It's a fallback safe method as old browsers fallback to px/em values that you probably are using on your site already. So this means no.
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