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                <div class="loader">
      <filter id="goo">
        <feGaussianBlur in="SourceGraphic" stdDeviation="2" result="blur" />
        <feColorMatrix in="blur" mode="matrix" values="1 0 0 0 0  0 1 0 0 0  0 0 1 0 0  0 0 0 5 -2" result="gooey" />
        <feComposite in="SourceGraphic" in2="gooey" operator="atop"/>


                // element vars
$scale: 36px
$speed: 2s

// quick and easy complementary colors
$angle: 25
$color-element: hsl($angle,100,65)
$color-background: hsl($angle+180,30,15)

html, body
  background: $color-background
  position: absolute
  overflow: hidden
  height: 100%
  width: 100%
  left: 0
  top: 0
@keyframes loader-spin
    transform: rotate( 0deg )
    transform: rotate( 360deg )
  position: absolute
  margin: -#{$scale/2} 0 0 -#{$scale/2}
  border: #{$scale*0.1} solid $color-element
  box-sizing: border-box
  overflow: hidden
  width: $scale
  height: $scale
  left: 50%
  top: 50%
  animation: loader-spin $speed linear infinite reverse
  // taken and tweaked from:
  filter: url(#goo)
  // hides a 1px render error in some browsers that
  // happens with transformed children inside an
  // overflow hidden parent. only a real issue
  // without the filter
  box-shadow: 0 0 0 1px $color-element inset

    content: ""
    position: absolute
    animation: loader-spin $speed cubic-bezier(.59,.25,.4,.69) infinite
    background: $color-element
    transform-origin: top center
    border-radius: 50%
    width: 150%
    height: 150%
    top: 50%
    left: -12.5%