//  Helper function to replace characters in a string
@function str-replace($string, $search, $replace-with: '') {
  $index: str-index($string, $search); 
  @return if($index, 
    str-slice($string, 1, $index - 1) + $replace-with + 
    str-replace(str-slice($string, $index + 
    str-length($search)), $search, $replace-with), 
    $string); 
}