SASS: mixins

_mixins.scss

@mixin bgSprite($left: 0, $top: 0, $width: auto, $height: auto, $img: $sprite, $repeat: no-repeat) {
    overflow: hidden;
    width: $width;
    height: $height;
    background: transparent $img (0 - $left) (0 - $top) $repeat;
}

@mixin roundEachCorner($tl: 0, $tr: 0, $br: 0, $bl: 0) {
    -webkit-border-top-left-radius: $tl;
    -webkit-border-top-right-radius: $tr;
    -webkit-border-bottom-right-radius: $br;
    -webkit-border-bottom-left-radius: $bl;
    -moz-border-radius: $tl $tr $br $bl;
    border-radius: $tl $tr $br $bl;
}

@mixin roundAllCorners($r: 0) {
    @include roundEachCorner($r, $r, $r, $r)
}

@mixin roundLeftCorners($r: 0) {
    @include roundEachCorner($r, 0, 0, $r)
}

@mixin roundTopCorners($r: 0) {
    @include roundEachCorner($r, $r, 0, 0)
}

@mixin roundRightCorners($r: 0) {
    @include roundEachCorner(0, $r, $r, 0)
}

@mixin roundBottomCorners($r: 0) {
    @include roundEachCorner(0, 0, $r, $r)
}

@mixin boxShadow($left: 0, $top: 0, $spread: 0, $color: #000) {
    -webkit-box-shadow: $left $top $spread $color;
    -moz-box-shadow: $left $top $spread $color;
    box-shadow: $left $top $spread $color;
}

@mixin gradient($top_color: #000, $bottom_color: #fff, $top_color_stop: 0, $bottom_color_stop: 1) {
    background: -webkit-gradient(linear, center top, center bottom, color-stop($top_color_stop, $top_color), color-stop($bottom_color_stop, $bottom_color));
    background: -moz-linear-gradient(center top, $top_color, $bottom_color);
    background: linear-gradient(center top, $top_color, $bottom_color);
    filter: progid:DXImageTransform.Microsoft.gradient(GradientType=0, startColorstr='$top_color', endColorstr='$bottom_color');
    -ms-filter: "progid:DXImageTransform.Microsoft.gradient(GradientType=0, startColorstr='#{$top_color}', endColorstr='#{$bottom_color}')";
}

@mixin opacity($val) {
    -moz-opacity: $val;
    -khtml-opacity: $val;
    opacity: $val;
    $val100: $val * 100;
    -ms-filter: "progid:DXImageTransform.Microsoft.Alpha(Opacity=#{$val100})";
    filter: alpha(opacity=$val100);
}

@mixin rotate($deg: 45deg) {
    -webkit-transform: rotate($deg);  
    -moz-transform: rotate($deg);  
    -ms-transform: rotate($deg);  
    -o-transform: rotate($deg);  
    transform: rotate($deg);
}