find a new compass animation syntax

animation.sass

// Mixins --------------------------------------------------------------

=keyframes($name)
  @-moz-keyframes #{$name}
    @children
  @-webkit-keyframes #{$name}
    @children
  @keyframes #{$name}
    @chldren

=animation-timing-function($function)
  -moz-animation-timing-function: $function
  -webkit-animation-timing-function: $function
  animation-timing-function: $function

// Application --------------------------------------------------------------

+keyframes('bounce')
  from
    +animation-timing-function(ease-out)
    top: 100px

  25%
    +animation-timing-function(ease-in)
    top: 50px

  50%
    +animation-timing-function(ease-out)
    top: 100px

  75%
    +animation-timing-function(ease-in)
    top: 75px

  to
    top: 100px