@mixin transform($property: none)
  // none | <transform-function>
  @include prefixer(transform, $property, webkit moz ms o spec)

@mixin placeholder
  $placeholders: ":-webkit-input" ":-moz" "-moz" "-ms-input"
  @each $placeholder in $placeholders
    &:#{$placeholder}-placeholder
      @content

@mixin appearance($value)
  @include prefixer(appearance, $value, webkit moz ms o spec)

@mixin animation-name($value)
  @include prefixer(animation-name, $value, webkit)
@mixin animation-duration($value)
  @include prefixer(animation-duration, $value, webkit)
@mixin animation-iteration-count($value)
  @include prefixer(animation-iteration-count, $value, webkit)