How to scale text size compared to container

Question

How would you scale text size based on container size. Other questions state it can\'t be done with css, if not how would you go about it?

Answer 1

I couldn't work out how to do it with CSS, so I used pure JS (don't need jquery).

var els = document.getElementsByClassName('abc')
for (var i = 0; i < els.length; i++){
    els[i].style.fontSize = els[i].clientHeight + 'px'
}

Example: http://jsfiddle.net/nickg1/H64mQ/