// Invert number
@function number-invert($number) {
  @return $number * -1;
}
@function invert($number) {
  @return number-invert($number);
}

// Round (shortcut)
@function decimal-round($number, $digits: 0, $mode: round) {
  $n: 1;
  // $number must be a number
  @if type-of($number) != number {
    @warn '#{$number} is not a number.';
    @return $number;
  }
  // $digits must be a unitless number
  @if type-of($digits) != number {
    @warn '#{ $digits} is not a number.';
    @return $number;
  } @else if not unitless($digits) {
    @warn '#{$digits} has a unit.';
    @return $number;
  }
  @for $i from 1 through $digits {
    $n: $n * 10;
  }
  @if $mode == round {
    @return round($number * $n) / $n;
  } @else if $mode == ceil {
    @return ceil($number * $n) / $n;
  } @else if $mode == floor {
    @return floor($number * $n) / $n;
  } @else {
    @warn '#{$mode} is undefined keyword.';
    @return $number;
  }
}
// @function round($number, $digits: 0, $mode: round){
// 	@return decimal-round($number, $digits: 0, $mode: round);
// }

// Ceil (shortcut)
@function decimal-ceil($number, $digits: 0) {
  @return decimal-round($number, $digits, ceil);
}

// Floor (shortcut)
@function decimal-floor($number, $digits: 0) {
  @return decimal-round($number, $digits, floor);
}