Description
Removes units from a CSS distance value with units, to return a number.
SCSS Usage
strip-units($number)
  Where $number can be a CSS distance value, such as 12px, 10em or 2rem.
And so, in SCSS:
.foo::before {
  content: strip-units(32px);
}
  Output
.foo::before {
  content: 32;
}
  Notes
Not an especially common need in SCSS, but useful when dealing with numbers to avoid unexpected - used in rem-calc.