_transition.scss

// Shorthand mixin. Supports multiple parentheses-deliminated values for each variable.
// Example: @include transition (all, 2.0s, ease-in-out);
//          @include transition ((opacity, width), (1.0s, 2.0s), ease-in, (0, 2s));
//          @include transition ($property:(opacity, width), $delay: (1.5s, 2.5s));
@mixin transition ($property: all, $duration: 0.15s, $timing-function: ease-out, $delay: 0) {
  // Detect # of args passed into each variable
  $length-of-property: length($property);
  $length-of-duration: length($duration);
  $length-of-timing-function: length($timing-function);
  $length-of-delay: length($delay);

  @if $length-of-property > 1 {
    @include transition-property(zip($property));
  } @else {
    @include transition-property(    $property);
  }

  @if $length-of-duration > 1 {
    @include transition-duration(zip($duration));
  } @else {
    @include transition-duration(    $duration);
  }

  @if $length-of-timing-function > 1 {
    @include transition-timing-function(zip($timing-function));
  } @else {
    @include transition-timing-function(    $timing-function);
  }

  @if $length-of-delay > 1 {
    @include transition-delay(zip($delay));
  } @else {
    @include transition-delay(    $delay);
  }
}


@mixin transition-property ($property-1: all,
  $property-2: false, $property-3: false,
  $property-4: false, $property-5: false,
  $property-6: false, $property-7: false,
  $property-8: false, $property-9: false)
  {
    $full: $property-1;
    @each $property in
      $property-2, $property-3,
      $property-4, $property-5,
      $property-6, $property-7,
      $property-8, $property-9{
        @if $property {
          $full: $full, $property;
        }
      }
  -webkit-transition-property: $full;
     -moz-transition-property: $full;
          transition-property: $full;
}

@mixin transition-duration ($time-1: 0,
  $time-2: false, $time-3: false,
  $time-4: false, $time-5: false,
  $time-6: false, $time-7: false,
  $time-8: false, $time-9: false)
  {
    $full: $time-1;
    @each $time in
      $time-2, $time-3,
      $time-4, $time-5,
      $time-6, $time-7,
      $time-8, $time-9{
        @if $time {
          $full: $full, $time;
        }
      }
  -webkit-transition-duration: $full;
     -moz-transition-duration: $full;
          transition-duration: $full;
}

@mixin transition-timing-function ($motion-1: ease,
  $motion-2: false, $motion-3: false,
  $motion-4: false, $motion-5: false,
  $motion-6: false, $motion-7: false,
  $motion-8: false, $motion-9: false)
  {
    $full: $motion-1;
    @each $motion in
      $motion-2, $motion-3,
      $motion-4, $motion-5,
      $motion-6, $motion-7,
      $motion-8, $motion-9{
        @if $motion {
          $full: $full, $motion;
        }
      }
// ease | linear | ease-in | ease-out | ease-in-out | cubic-bezier()
  -webkit-transition-timing-function: $full;
     -moz-transition-timing-function: $full;
          transition-timing-function: $full;
}

@mixin transition-delay ($time-1: 0,
  $time-2: false, $time-3: false,
  $time-4: false, $time-5: false,
  $time-6: false, $time-7: false,
  $time-8: false, $time-9: false)
  {
    $full: $time-1;
    @each $time in
      $time-2, $time-3,
      $time-4, $time-5,
      $time-6, $time-7,
      $time-8, $time-9{
        @if $time {
          $full: $full, $time;
        }
      }
  -webkit-transition-delay: $full;
     -moz-transition-delay: $full;
          transition-delay: $full;
}