@mixin gradient ($c2, $c1)
  background-image: -webkit-linear-gradient(top, $c1 0%, $c2 100%)
  background-image: -moz-linear-gradient(top, $c1 0%, $c2 100%)
  background-image: -o-linear-gradient(top, $c1 0%, $c2 100%)
  background-image: -ms-linear-gradient(top, $c1 0%, $c2 100%)
  background-image: linear-gradient(top, $c1 0%, $c2 100%)
  filter: progid:DXImageTransform.Microsoft.gradient(startColorStr='$c2', EndColorStr='$c1')

@mixin box-shadow($data)
  -webkit-box-shadow: #{$data}
  -moz-box-shadow: #{$data}
  box-shadow: #{$data}

@mixin line-height($height)
  height: $height
  line-height: $height

@mixin font($size: inherit, $weight: inherit, $line-height: 20px, $family: "'Helvetica Neue', Helvetica, Arial, sans-serif")
  $slash: '/'
  font: $weight $size #{$slash} $line-height #{$family}

@mixin border-radius ($r1: 4px, $r2: default, $r3: default, $r4: default)
  @if $r2 == default and $r3 == default and $r4 == default
    -webkit-border-radius: $r1
    -moz-border-radius: $r1
    border-radius: $r1

  @if $r2 != default
    -webkit-border-top-left-radius: $r1
    -moz-border-radius-topleft: $r1
    border-top-left-radius: $r1
    -webkit-border-top-right-radius: $r2
    -moz-border-radius-topright: $r2
    border-top-right-radius: $r2
    -webkit-border-bottom-right-radius: $r3
    -moz-border-radius-bottomright: $r3
    border-bottom-right-radius: $r3
    -webkit-border-bottom-left-radius: $r4
    -moz-border-radius-bottomleft: $r4
    border-bottom-left-radius: $r4