Include a rem-calc() function in utilities

Created by: liquidvisual

I think Foundation handles this well, you enter in a pixel value (or multiple) and the output is in rem units.

Eg.

rem-calc(56) 

...or for shorthand properties:

rem-calc(56 56 56 10) 

I find this particularly helpful when editing values in the variables file. It's a lot easier to think in pixels but output in rems. Especially if you're working off a PSD.

Take this for example:

$font-size-h1: 2.5rem   

What is 2.5rem? It doesn't mean much to me. I need to run this through an online rem convertor before I can figure out what it actually is.

In my opinion, this is much easier to understand quickly:

$font-size-h1: rem-calc(40); // 2.5rem