Sonya Style - SASS/Compass Button @mixin. This is my first mixin ever :)

_sonya-button.sass

// Button Mixin ------------------------------------------------------------------------------------
@mixin sonya_button($button_color: rgba(62,184,229,1), $borderRadius: 5px, $scale_border_lightness_by: -20%, $scale_border_saturation_by: -62%, $border_side: false, $isPushable: false, $pushable_highlight: 10%, $button_shadow_tint: 14%, $has_shadow: true) {
  // Box

  // Positioning
  position: relative;
  top: 0;

  // Background Color
  background-color: $button_color; // Old browsers
  @include filter-gradient(scale-lightness($button_color, 25%), $button_color, vertical); // IE6-9
  @include background-image(linear-gradient(top,  scale-lightness($button_color, 25%) 0%,$button_color 100%));
  @if $isPushable {
    &:active, &:hover {
      background-color: scale-lightness($button_color, $pushable_highlight); // Old browsers
      @include filter-gradient(scale-lightness($button_color, (25% + $pushable_highlight)), scale-lightness($button_color, $pushable_highlight), vertical); // IE6-9
      @include background-image(linear-gradient(top,  scale-lightness($button_color, (25% + $pushable_highlight)) 0%,scale-lightness($button_color, $pushable_highlight) 100%));
      cursor: pointer;
    }
  }

  // Border
  @if $border_side {
    border-#{$border_side}: 1px solid scale-saturation(scale-lightness($button_color, $scale_border_lightness_by), $scale_border_saturation_by);
    @if $border_side == "left" {
      @include border-radius(0px $borderRadius $borderRadius 0px);
    } @else if $border_side == "right" {
      @include border-radius($borderRadius 0px 0px $borderRadius);
    }
  } @else {
      @include border-radius($borderRadius);
  }

  // Box Shadow
  @if $has_shadow {
    @include box-shadow(inset 0px 1px 0px scale-lightness($button_color, 50%), 0px 5px 0px 0px scale-saturation(scale-lightness($button_color, -38%), -38%), 0px 12px 10px -3px scale-saturation(scale-lightness($button_color, $button_shadow_tint), -80%));  
    @if $isPushable {
      &:active {
        top: 3px;
        @if $border_side == "left" {
          @include box-shadow(inset 5px 0px 10px -6px scale-saturation(scale-lightness($button_color, -80%), -80%), inset 0px 1px 0px scale-lightness($button_color, 50%), 0px 2px 0px 0px scale-saturation(scale-lightness($button_color, -38%), -38%), 0px 9px 7px -4px scale-saturation(scale-lightness($button_color, $button_shadow_tint), -80%));      
        } @else if $border_side == "right" {
          @include box-shadow(inset -5px 0px 10px -6px scale-saturation(scale-lightness($button_color, -80%), -80%), inset 0px 1px 0px scale-lightness($button_color, 50%), 0px 2px 0px 0px scale-saturation(scale-lightness($button_color, -38%), -38%), 0px 9px 7px -4px scale-saturation(scale-lightness($button_color, $button_shadow_tint), -80%));      
        } @else {
          @include box-shadow(inset 0px 1px 0px scale-lightness($button_color, 50%), 0px 2px 0px 0px scale-saturation(scale-lightness($button_color, -38%), -38%), 0px 9px 7px -4px scale-saturation(scale-lightness($button_color, $button_shadow_tint), -80%));
        }
      }
    }
  }
}