<!DOCTYPE HTML>
<style>
div { font-size: 12px; line-height: 1.0; width: 450px }
input { font-size: 12px; }
</style>
<div><input type="radio">In a 450px container, the minimum font size at 15em per line is 30px.
This means we map 0px-45px into 30px-45px, so 12px gets mapped to 34px.</div>