max-height with em

A max-height solution for Firefox using font-size and em instead of width and %

by Maximilian Lindsey

HTML

<div>
    <p>
        <img src="http://g1.img-dpreview.com/F6E5AEB2052943939E153C1D8B8D833A.jpg" alt="">    
    </p>    
</div>

CSS

html,body{
    font-size: 100%;
}
img{
    max-width: 100%;
    max-height: 50em;
}