@mixin background-size ($width: 100%, $height: auto) {
  -moz-background-size:$width $height;
  -webkit-background-size:$width $height;
  background-size:$width $height;
}

@mixin border-radius($radius: 5px) {
  -webkit-border-radius: $radius;
     -moz-border-radius: $radius;
      -ms-border-radius: $radius;
          border-radius: $radius;
}
@mixin border-radiuses ($topright: 0, $bottomright: 0, $bottomleft: 0, $topleft: 0) {
  -webkit-border-top-right-radius:    $topright;
  -webkit-border-bottom-right-radius: $bottomright;
  -webkit-border-bottom-left-radius:  $bottomleft;
  -webkit-border-top-left-radius:     $topleft;

  -moz-border-radius-topright:        $topright;
  -moz-border-radius-bottomright:     $bottomright;
  -moz-border-radius-bottomleft:      $bottomleft;
  -moz-border-radius-topleft:         $topleft;

  border-top-right-radius:            $topright;
  border-bottom-right-radius:         $bottomright;
  border-bottom-left-radius:          $bottomleft;
  border-top-left-radius:             $topleft;
}
@mixin box-sizing($sizing: border-box) {
  -ms-box-sizing: $sizing;
  -moz-box-sizing: $sizing;
  -webkit-box-sizing: $sizing;
  box-sizing: $sizing;
}
@mixin transition ($property: color, $time: .1s, $type: linear, $property2: color) {
  -webkit-transition:$property $time $type, $property2 $time $type;
  -moz-transition:$property $time $type, $property2 $time $type;
  -o-transition:$property $time $type, $property2 $time $type;
  transition:$property $time $type, $property2 $time $type;
}
@mixin background-stripe ($percent: 50%, $from_col: #000, $to_col: #fff) {
  background: -moz-linear-gradient(left, $from_col 0%, $from_col $percent, $to_col $percent, $to_col 100%);
  background: -webkit-gradient(left top, right top, color-stop(0%, $from_col), color-stop($percent, $from_col), color-stop($percent, $to_col), color-stop(100%, $to_col));
  background: -webkit-linear-gradient(left, $from_col 0%, $from_col $percent, $to_col $percent, $to_col 100%);
  background: -o-linear-gradient(left, $from_col 0%, $from_col $percent, $to_col $percent, $to_col 100%);
  background: -ms-linear-gradient(left, $from_col 0%, $from_col $percent, $to_col $percent, $to_col 100%);
  background: linear-gradient(to right, $from_col 0%, $from_col $percent, $to_col $percent, $to_col 100%);
}
@mixin rotate($deg: 45deg) {
    -ms-transform: rotate($deg); /* IE 9 */
    -webkit-transform: rotate($deg); /* Chrome, Safari, Opera */
    transform: rotate($deg);
}
@mixin bw($amount: 100%) {
  -webkit-filter: grayscale($amount);
  -moz-filter: grayscale($amount);
  filter: grayscale($amount);
}