Sass function to work out EM's.

all.scss

//Work out EM for font sizes etc.

// USAGE: font-size: em(12);
// USAGE: font-size: em(12, 16);

@function em($target, $parent: strip-units($body_base_font_size)) {
  @return ($target / $parent) + em;
}

//Used for the EM function above - Removes units from a number
@function strip-units($number) {
	@return $number / ($number * 0 + 1);
}