//
// Compatibility
// -----------------------------------------------------------------------------
//
// ### Usage:
// Used to resolve common compatibility issues.
// Use Autoprefixer to handle vendor prefixes.
// Related mixins are preserved for backward compatibility.

@import "variables.less";

.inline-block() {
    display: inline-block;
}
.ie-inline-block() {
    *display: inline;
    *zoom: 1;
}
.inline-block() when (@support-ie-version < 8) {
    .ie-inline-block();
}

//
// Box sizing
.box-sizing(@boxmodel) when not (@use-autoprefixer) {
    -webkit-box-sizing: @boxmodel;
       -moz-box-sizing: @boxmodel;
            box-sizing: @boxmodel;
}
.box-sizing(@boxmodel) when (@use-autoprefixer) {
    box-sizing: @boxmodel;
}

//
// Reference:
// * http://css-tricks.com/snippets/css/style-placeholder-text/
// * https://bugzilla.mozilla.org/show_bug.cgi?id=737786
//
// Known issue:
// Not supported for IE9-
.placeholder(@style: @default-input-placeholder-color) when not (@use-autoprefixer) {
    .output() when (iscolor(@style)) {
        &::-webkit-input-placeholder {
            color: @style;
        }
        &:-moz-placeholder {
            color: @style;
        }
        &::-moz-placeholder {
            color: @style;
        }
        &:-ms-input-placeholder {
            color: @style;
        }
    }
    .output() when (isruleset(@style)) {
        &::-webkit-input-placeholder {
            @style();
        }
        &:-moz-placeholder {
            @style();
        }
        &::-moz-placeholder {
            @style();
        }
        &:-ms-input-placeholder {
            @style();
        }
    }
    .output();
}
.placeholder(@style: @default-input-placeholder-color) when (@use-autoprefixer) {
    .output() when (iscolor(@style)) {
        &::placeholder {
            color: @style;
        }
    }
    .output() when (isruleset(@style)) {
        &::placeholder {
            @style();
        }
    }
    .output();
}


//
// Known issue:
// Not supported for Opera 14-
.user-select(@type) when not (@use-autoprefixer) {
    -webkit-user-select: @type;
       -moz-user-select: @type;
        -ms-user-select: @type;
            user-select: @type;
}
.user-select(@type) when (@use-autoprefixer) {
    user-select: @type;
}

// Opacity
// In IE9, when `opacity` is set, alpha filter will be ignored
.opacity(@opacity: 100%) {
    opacity: unit(@opacity) / 100;
}
.opacity(@opacity: 100%) when (@support-ie-version < 9) {
    @op: unit(@opacity);
    filter: ~"alpha(opacity=@{op})";
}

// Single background with RGBA color
.rgba-background(@rgba) when (@support-ie-version < 9) {
    // prevent click through in IE 8 using a transparent background image
    background: ~"url(data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7) repeat\0";
    @argb: argb(@rgba);
    filter: ~"progid:DXImageTransform.Microsoft.gradient(startColorstr=@{argb},endColorstr=@{argb})\0";
    zoom: ~"1\0";
    background: @rgba;
    // hack for IE9 to prevent applying rgba and filter at the same time
    :root & {
        filter: none\9;
    }
}
.rgba-background(@rgba) when not (@support-ie-version < 9) {
    background: @rgba;
}
.rgba-background(@color, @opacity) {
    @op: unit(@opacity);
    @rgba: fadeout(@color, percentage((100 - @op) / 100));
    .rgba-background(@rgba);
}

// Border Radius

// all
.border-radius(@radius: @default-border-radius) when not (@use-autoprefixer) {
    -webkit-border-radius: @radius;
       -moz-border-radius: @radius;
            border-radius: @radius;
}
.border-radius(@radius: @default-border-radius) when (@use-autoprefixer) {
    border-radius: @radius;
}
.border-radius(@radius-x, @radius-y) {
    .border-radius(@radius-x ~"/" @radius-y);
}

// top left
.border-top-left-radius(@radius) when not (@use-autoprefixer) {
    -webkit-border-top-left-radius: @radius;
        -moz-border-radius-topleft: @radius;
            border-top-left-radius: @radius;
}
.border-top-left-radius(@radius) when (@use-autoprefixer) {
    border-top-left-radius: @radius;
}
.border-top-left-radius(@radius-x, @radius-y) {
    .border-top-left-radius(@radius-x ~"/" @radius-y);
}

// top right
.border-top-right-radius(@radius) when not (@use-autoprefixer) {
    -webkit-border-top-right-radius: @radius;
        -moz-border-radius-topright: @radius;
            border-top-right-radius: @radius;
}
.border-top-right-radius(@radius) when (@use-autoprefixer) {
    border-top-right-radius: @radius;
}
.border-top-right-radius(@radius-x, @radius-y) {
    .border-top-right-radius(@radius-x ~"/" @radius-y)
}

// bottom right
.border-bottom-right-radius(@radius) when not (@use-autoprefixer) {
    -webkit-border-bottom-right-radius: @radius;
        -moz-border-radius-bottomright: @radius;
            border-bottom-right-radius: @radius;
}
.border-bottom-right-radius(@radius) when (@use-autoprefixer) {
    border-bottom-right-radius: @radius;
}
.border-bottom-right-radius(@radius-x, @radius-y) {
    .border-bottom-right-radius(@radius-x ~"/" @radius-y)
}

// bottom left
.border-bottom-left-radius(@radius) when not (@use-autoprefixer) {
    -webkit-border-bottom-left-radius: @radius;
        -moz-border-radius-bottomleft: @radius;
            border-bottom-left-radius: @radius;
}
.border-bottom-left-radius(@radius) when (@use-autoprefixer) {
    border-bottom-left-radius: @radius;
}
.border-bottom-left-radius(@radius-x, @radius-y) {
    .border-bottom-left-radius(@radius-x ~"/" @radius-y);
}

// top
.border-top-radius(@radius) {
    .border-top-left-radius(@radius);
    .border-top-right-radius(@radius);
}
.border-top-radius(@radius-x, @radius-y) {
    .border-top-radius(@radius-x ~"/" @radius-y);
}

// right
.border-right-radius(@radius) {
    .border-top-right-radius(@radius);
    .border-bottom-right-radius(@radius);
}
.border-right-radius(@radius-x, @radius-y) {
    .border-right-radius(@radius-x ~"/" @radius-y);
}

// bottom
.border-bottom-radius(@radius) {
    .border-bottom-right-radius(@radius);
    .border-bottom-left-radius(@radius);
}
.border-bottom-radius(@radius-x, @radius-y) {
    .border-bottom-radius(@radius-x ~"/" @radius-y);
}

// left
.border-left-radius(@radius) {
    .border-top-left-radius(@radius);
    .border-bottom-left-radius(@radius);
}
.border-left-radius(@radius-x, @radius-y) {
    .border-left-radius(@radius-x ~"/" @radius-y);
}

//
// Drop shadows
.box-shadow(@shadow: @default-box-shadow, ...) when not (@use-autoprefixer) {
    @shadows: ~`(function() { var args = "@{arguments}".replace(/[[\]]/g, ""); if(!args.match(/[^,]\s+[^,]/)) { args = args.replace(/,(?=[^()]*\))/g, "%est%").replace(/,/g, "").replace(/%est%/g, ","); } return args;})()`;
    -webkit-box-shadow: @shadows;
       -moz-box-shadow: @shadows;
            box-shadow: @shadows;
}
.box-shadow(@shadow: @default-box-shadow, ...) when (@use-autoprefixer) {
    @shadows: ~`(function() { var args = "@{arguments}".replace(/[[\]]/g, ""); if(!args.match(/[^,]\s+[^,]/)) { args = args.replace(/,(?=[^()]*\))/g, "%est%").replace(/,/g, "").replace(/%est%/g, ","); } return args;})()`;
    box-shadow: @shadows;
}

// Transitions
// Reference:
// * https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_animated_properties
.transition(@transition, ...) when not (@use-autoprefixer) {
    @transitions: ~`(function() { var args = "@{arguments}".replace(/[[\]]/g, ""); if(!args.match(/[^,]\s+[^,]/)) { args = args.replace(/,(?=[^()]*\))/g, "%est%").replace(/,/g, "").replace(/%est%/g, ","); } return args;})()`;
    @webkit-transitions: ~`"@{transitions}".replace(/(transform|perspective|border(?:-\w+)*?-radius|box-shadow)/g, "-webkit-$1")`;
    @moz-transitions: ~`"@{transitions}".replace(/(transform|perspective|border(?:-\w+)*?-radius|box-shadow)/g, "-moz-$1")`;
    @o-transitions: ~`"@{transitions}".replace(/(transform|perspective|border(?:-\w+)*?-radius|box-shadow)/g, "-o-$1")`;
    -webkit-transition: @webkit-transitions;
       -moz-transition: @moz-transitions;
         -o-transition: @o-transitions;
            transition: @transitions;
}
.transition(@transition, ...) when (@use-autoprefixer) {
    @transitions: ~`(function() { var args = "@{arguments}".replace(/[[\]]/g, ""); if(!args.match(/[^,]\s+[^,]/)) { args = args.replace(/,(?=[^()]*\))/g, "%est%").replace(/,/g, "").replace(/%est%/g, ","); } return args;})()`;
    transition: @transitions;
}

.transition-property(@property: all, ...) when not (@use-autoprefixer) {
    @properties: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    @webkit-properties: ~`"@{properties}".replace(/(transform|perspective|border(?:-\w+)*?-radius|box-shadow)/g, "-webkit-$1")`;
    @moz-properties: ~`"@{properties}".replace(/(transform|perspective|border(?:-\w+)*?-radius|box-shadow)/g, "-moz-$1")`;
    @o-properties: ~`"@{properties}".replace(/(transform|perspective|border(?:-\w+)*?-radius|box-shadow)/g, "-o-$1")`;
    -webkit-transition-property: @webkit-properties;
       -moz-transition-property: @moz-properties;
         -o-transition-property: @o-properties;
            transition-property: @properties;
}
.transition-property(@property: all, ...) when (@use-autoprefixer) {
    @properties: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    transition-property: @properties;
}

.transition-duration(@duration: 0s, ...) when not (@use-autoprefixer) {
    @durations: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-transition-duration: @durations;
       -moz-transition-duration: @durations;
         -o-transition-duration: @durations;
            transition-duration: @durations;
}
.transition-duration(@duration: 0s, ...) when (@use-autoprefixer) {
    @durations: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    transition-duration: @durations;
}

.transition-timing-function(@timing-function: ease, ...) when not (@use-autoprefixer) {
    @timing-functions: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-transition-timing-function: @timing-functions;
       -moz-transition-timing-function: @timing-functions;
         -o-transition-timing-function: @timing-functions;
            transition-timing-function: @timing-functions;
}
.transition-timing-function(@timing-function: ease, ...) when (@use-autoprefixer) {
    @timing-functions: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    transition-timing-function: @timing-functions;
}

.transition-delay(@delay: 0s, ...) when not (@use-autoprefixer) {
    @delays: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-transition-delay: @delays;
       -moz-transition-delay: @delays;
         -o-transition-delay: @delays;
            transition-delay: @delays;
}
.transition-delay(@delay: 0s, ...) when (@use-autoprefixer) {
    @delays: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    transition-delay: @delays;
}

//
// Animations
//
// Reference:
// * https://developer.mozilla.org/en-US/docs/Web/CSS/animation
.animation(@animation, ...) when not (@use-autoprefixer) {
    @animations: ~`(function() { var args = "@{arguments}".replace(/[[\]]/g, ""); if(!args.match(/[^,]\s+[^,]/)) { args = args.replace(/,(?=[^()]*\))/g, "%est%").replace(/,/g, "").replace(/%est%/g, ","); } return args;})()`;
    -webkit-animation: @animations;
       -moz-animation: @animations;
         -o-animation: @animations;
            animation: @animations;
}
.animation(@animation, ...) when (@use-autoprefixer) {
    @animations: ~`(function() { var args = "@{arguments}".replace(/[[\]]/g, ""); if(!args.match(/[^,]\s+[^,]/)) { args = args.replace(/,(?=[^()]*\))/g, "%est%").replace(/,/g, "").replace(/%est%/g, ","); } return args;})()`;
    animation: @animations;
}

.animation-name(@name: none, ...) when not (@use-autoprefixer) {
    @names: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-animation-name: @names;
       -moz-animation-name: @names;
         -o-animation-name: @names;
            animation-name: @names;
}
.animation-name(@name: none, ...) when (@use-autoprefixer) {
    @names: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    animation-name: @names;
}

.animation-duration(@duration: 0s, ...) when not (@use-autoprefixer) {
    @durations: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-animation-duration: @durations;
       -moz-animation-duration: @durations;
         -o-animation-duration: @durations;
            animation-duration: @durations;
}
.animation-duration(@duration: 0s, ...) when (@use-autoprefixer) {
    @durations: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    animation-duration: @durations;
}

.animation-timing-function(@timing-function: ease, ...) when not (@use-autoprefixer) {
    @timing-functions: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-animation-timing-function: @timing-functions;
       -moz-animation-timing-function: @timing-functions;
         -o-animation-timing-function: @timing-functions;
            animation-timing-function: @timing-functions;
}
.animation-timing-function(@timing-function: ease, ...) when (@use-autoprefixer) {
    @timing-functions: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    animation-timing-function: @timing-functions;
}

.animation-iteration-count(@count: 1, ...) when not (@use-autoprefixer) {
    @counts: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-animation-iteration-count: @counts;
       -moz-animation-iteration-count: @counts;
         -o-animation-iteration-count: @counts;
            animation-iteration-count: @counts;
}
.animation-iteration-count(@count: 1, ...) when (@use-autoprefixer) {
    @counts: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    animation-iteration-count: @counts;
}

.animation-direction(@direction: normal, ...) when not (@use-autoprefixer) {
    @directions: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-animation-direction: @directions;
       -moz-animation-direction: @directions;
         -o-animation-direction: @directions;
            animation-direction: @directions;
}
.animation-direction(@direction: normal, ...) when (@use-autoprefixer) {
    @directions: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    animation-direction: @directions;
}

.animation-play-state(@state: running, ...) when not (@use-autoprefixer) {
    @states: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-animation-play-state: @states;
       -moz-animation-play-state: @states;
         -o-animation-play-state: @states;
            animation-play-state: @states;
}
.animation-play-state(@state: running, ...) when (@use-autoprefixer) {
    @states: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    animation-play-state: @states;
}

.animation-delay(@delay: 0s, ...) when not (@use-autoprefixer) {
    @delays: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-animation-delay: @delays;
       -moz-animation-delay: @delays;
         -o-animation-delay: @delays;
            animation-delay: @delays;
}
.animation-delay(@delay: 0s, ...) when (@use-autoprefixer) {
    @delays: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    animation-delay: @delays;
}

.animation-fill-mode(@mode: none, ...) when not (@use-autoprefixer) {
    @modes: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-animation-fill-mode: @modes;
       -moz-animation-fill-mode: @modes;
         -o-animation-fill-mode: @modes;
            animation-fill-mode: @modes;
}
.animation-fill-mode(@mode: none, ...) when (@use-autoprefixer) {
    @modes: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    animation-fill-mode: @modes;
}

//
// Transformations
//
// Reference:
// * https://developer.mozilla.org/en-US/docs/Web/CSS/transform
// * http://dev.w3.org/csswg/css-transforms/#transform
.transform(...) when not (@use-autoprefixer) {
    -webkit-transform: @arguments;
       -moz-transform: @arguments;
        -ms-transform: @arguments;
         -o-transform: @arguments;
            transform: @arguments;
}
.transform(...) when (@use-autoprefixer) {
    transform: @arguments;
}

// Known issue:
// Not supported for IE, Opera 14-
.transform-style(@style) when not (@use-autoprefixer) {
    -webkit-transform-style: @style;
       -moz-transform-style: @style;
            transform-style: @style;
}
.transform-style(@style) when (@use-autoprefixer) {
    transform-style: @style;
}

//
// Known issue:
// Triple value grammar not supported for Opera 14-
.transform-origin(@origin) when not (@use-autoprefixer) {
    -webkit-transform-origin: @origin;
       -moz-transform-origin: @origin;
        -ms-transform-origin: @origin;
         -o-transform-origin: @origin;
            transform-origin: @origin;
}
.transform-origin(@origin) when (@use-autoprefixer) {
    transform-origin: @origin;
}

//
// Known issue:
// Not supported for IE9, Opera 14-
.backface-visibility(@visibility) when not (@use-autoprefixer) {
    -webkit-backface-visibility: @visibility;
       -moz-backface-visibility: @visibility;
            backface-visibility: @visibility;
}
.backface-visibility(@visibility) when (@use-autoprefixer) {
    backface-visibility: @visibility;
}

//
// Known issue:
// Not supported for IE9, Opera 14-
.perspective(@d) when not (@use-autoprefixer) {
    -webkit-perspective: @d;
       -moz-perspective: @d;
            perspective: @d;
}
.perspective(@d) when (@use-autoprefixer) {
    perspective: @d;
}

//
// Single transform function
.transform-single(@transform-function, @rest...) {
    @args: ~`"@{rest}".replace(/[\[\]]/g, "")`;
    .output(false) {
        -webkit-transform: ~`"@{transform-function}(@{args})"`;
           -moz-transform: ~`"@{transform-function}(@{args})"`;
            -ms-transform: ~`"@{transform-function}(@{args})"`;
             -o-transform: ~`"@{transform-function}(@{args})"`;
                transform: ~`"@{transform-function}(@{args})"`;
    }
    .output(true) {
        transform: ~`"@{transform-function}(@{args})"`;
    }
    .output(@use-autoprefixer);
}

// 2D transform functions
.matrix(@a, @b, @c, @d, @tx, @ty) {
    .transform-single(matrix, @arguments);
}

.translate(@tx) {
    .transform-single(translate, @arguments);
}
.translate(@tx, @ty) {
    .transform-single(translate, @arguments);
}

.translateX(@tx) {
    .transform-single(translateX, @arguments);
}

.translateY(@ty) {
    .transform-single(translateY, @arguments);
}

.scale(@sx) {
    .transform-single(scale, @arguments);
}
.scale(@sx, @sy) {
    .transform-single(scale, @arguments);
}

.scaleX(@sx) {
    .transform-single(scaleX, @arguments);
}

.scaleY(@sy) {
    .transform-single(scaleY, @arguments);
}

.rotate(@angle) {
    .transform-single(rotate, @arguments);
}

.skew(@ax) {
    .transform-single(skew, @arguments);
}
.skew(@ax, @ay) {
    .transform-single(skew, @arguments);
}

.skewX(@ax) {
    .transform-single(skewX, @arguments);
}

.skewY(@ay) {
    .transform-single(skewY, @arguments);
}

// 3D transform  functions
.matrix3d(@a1, @b1, @c1, @d1, @a2, @b2, @c2, @d2,
           @a3, @b3, @c3, @d3, @a4, @b4, @c4, @d4) {
    .transform-single(matrix3d, @arguments);
}

.translate3d(@tx, @ty, @tz) {
    .transform-single(translate3d, @arguments);
}

.translateZ(@tz) {
    .transform-single(translateZ, @arguments);
}

.scale3d(@sx, @sy, @sz) {
    .transform-single(scale3d, @arguments);
}

.scaleZ(@sz) {
    .transform-single(scaleZ, @arguments);
}

.rotate3d(@x, @y, @z, @angle) {
    .transform-single(rotate3d, @arguments);
}

.rotateX(@angle) {
    .transform-single(rotateX, @arguments);
}

.rotateY(@angle) {
    .transform-single(rotateY, @arguments);
}

.rotateZ(@angle) {
    .transform-single(rotateZ, @arguments);
}

.transform-perspective(@d) {
    .transform-single(perspective, @d);
}

//
// CSS3 Background

// Background clip
// FF 3.6 and under need "padding" instead of "padding-box"
.background-clip(@clip, ...) when not (@use-autoprefixer) {
    @clips: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-background-clip: @clips;
       -moz-background-clip: ~`"@{clips}".replace(/-box/g, "")`;
         -o-background-clip: @clips;
            background-clip: @clips;
}
.background-clip(@clip, ...) when (@use-autoprefixer) {
    @clips: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    background-clip: @clips;
}

// Background sizing
.background-size(@size, ...) when not (@use-autoprefixer) {
    @sizes: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-background-size: @sizes;
       -moz-background-size: @sizes;
         -o-background-size: @sizes;
            background-size: @sizes;
}
.background-size(@size, ...) when (@use-autoprefixer) {
    @sizes: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    background-size: @sizes;
}

// Background origin
// FF 3.6 and under need "padding" instead of "padding-box"
.background-origin(@origin, ...) when not (@use-autoprefixer) {
    @origins: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    -webkit-background-origin: @origins;
       -moz-background-origin: ~`"@{origins}".replace(/-box/g, "")`;;
         -o-background-origin: @origins;
            background-origin: @origins;
}
.background-origin(@origin, ...) when (@use-autoprefixer) {
    @origins: ~`"@{arguments}".replace(/[\[\]]/g, "")`;
    background-origin: @origins;
}

//
// Gradients

// General linear-gradient
.linear-gradient(@direction, @color-stop...) {
    @dir: ~`"@{direction}".replace(/[\[\],]/g, "")`;
    @is-old-side-or-corner: ~`/^(?:top|right|bottom|left)(?:\s+(?:top|right|bottom|left))?$/.test("@{dir}") ? "true" : "false"`;
    @is-standard-side-or-corner: ~`/^to\s+(?:top|right|bottom|left)(?:\s+(?:top|right|bottom|left))?$/.test("@{dir}") ? "true" : "false"`;
    @color-stops: ~`"@{color-stop}".replace(/[\[\]]/g, "")`;
    .output() when (@is-old-side-or-corner) {
        @standard-direction: ~`"to @{dir}".replace("top", "b#ottom").replace("right", "l#eft").replace("bottom", "t#op").replace("left", "r#ight").replace(/#/g, "")`;
        .output(false) {
            background-image: -webkit-linear-gradient(@dir, @color-stops); // Chrome 10+
            background-image: -moz-linear-gradient(@dir, @color-stops); // Firefox 3.6+
            background-image: -moz-linear-gradient(@standard-direction, @color-stops); // Firefox 10+
            background-image: -o-linear-gradient(@standard-direction, @color-stops); // Opera 11.10+
        }
        .output(...) {
            background-image: linear-gradient(@standard-direction, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.10+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output() when (@is-standard-side-or-corner) {
        @old-direction: ~`"@{dir}".replace(/^to\s+/, "").replace("top", "b#ottom").replace("right", "l#eft").replace("bottom", "t#op").replace("left", "r#ight").replace(/#/g, "")`;
        .output(false) {
            background-image: -webkit-linear-gradient(@old-direction, @color-stops); // Chrome 10+
            background-image: -moz-linear-gradient(@old-direction, @color-stops); // Firefox 3.6+
            background-image: -moz-linear-gradient(@dir, @color-stops); // Firefox 10+
            background-image: -o-linear-gradient(@dir, @color-stops); // Opera 11.10+
        }
        .output(...) {
            background-image: linear-gradient(@dir, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.10+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output() when not (@is-old-side-or-corner) and not (@is-standard-side-or-corner) {
        .output(false) {
            background-image: -webkit-linear-gradient(mod(abs(convert(@direction, deg) - 450), 360), @color-stops); // Chrome 10+
            background-image: -moz-linear-gradient(mod(abs(convert(@direction, deg) - 450), 360), @color-stops); // Firefox 3.6+
            background-image: -o-linear-gradient(mod(abs(convert(@direction, deg) - 450), 360), @color-stops); // Opera 11.10+
        }
        .output(...) {
            background-image: linear-gradient(@direction, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.10+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output();
    background-repeat: repeat;
}

// Horizontal gradient with better browser compatibility
.horizontal-gradient(@start-color, @end-color) {
    .output(false) {
        background-image: -webkit-gradient(linear, left top, right top, from(@start-color), to(@end-color)); // Safari 4+, Chrome 2+
        background-image: -webkit-linear-gradient(left, @start-color, @end-color); // Safari 5.1+, Chrome 10+
        background-image: -moz-linear-gradient(left, @start-color, @end-color); // FF 3.6+
        background-image: -o-linear-gradient(left, @start-color, @end-color); // Opera 11.10+
    }
    .output(...) {
        background-image: linear-gradient(to right, @start-color, @end-color); // Standard, IE10
        background-repeat: repeat-x;
    }
    .output(...) when (@support-ie-version < 10) {
        filter: e(%("progid:DXImageTransform.Microsoft.Gradient(startColorstr='%d', endColorstr='%d', GradientType=1)", argb(@start-color), argb(@end-color))); // IE9 and down
    }
    .output(@use-autoprefixer);
}

// Vertical gradient with better browser compatibility
.vertical-gradient(@start-color, @end-color) {
    .output(false) {
        background-image: -webkit-gradient(linear, left top, left bottom, from(@start-color), to(@end-color)); // Safari 4+, Chrome 2+
        background-image: -webkit-linear-gradient(top, @start-color, @end-color); // Safari 5.1+, Chrome 10+
        background-image: -moz-linear-gradient(top, @start-color, @end-color); // FF 3.6+
        background-image: -o-linear-gradient(top, @start-color, @end-color); // Opera 11.10+
    }
    .output(...) {
        background-image: linear-gradient(to bottom, @start-color, @end-color); // Standard, IE10
        background-repeat: repeat-x;
    }
    .output(...) when (@support-ie-version < 10) {
        filter: e(%("progid:DXImageTransform.Microsoft.Gradient(startColorstr='%d', endColorstr='%d', GradientType=0)", argb(@start-color), argb(@end-color))); // IE9 and down
    }
    .output(@use-autoprefixer);
}

// General repeating linear-gradient
.repeating-linear-gradient(@direction, @color-stop...) {
    @dir: ~`"@{direction}".replace(/[\[\],]/g, "")`;
    @is-old-side-or-corner: ~`/^(?:top|right|bottom|left)(?:\s+(?:top|right|bottom|left))?$/.test("@{dir}") ? "true" : "false"`;
    @is-standard-side-or-corner: ~`/^to\s+(?:top|right|bottom|left)(?:\s+(?:top|right|bottom|left))?$/.test("@{dir}") ? "true" : "false"`;
    @color-stops: ~`"@{color-stop}".replace(/[\[\]]/g, "")`;
    .output() when (@is-old-side-or-corner) {
        @standard-direction: ~`"to @{dir}".replace("top", "b#ottom").replace("right", "l#eft").replace("bottom", "t#op").replace("left", "r#ight").replace(/#/g, "")`;
        .output(false) {
            background-image: -webkit-repeating-linear-gradient(@dir, @color-stops); // Chrome 10+
            background-image: -moz-repeating-linear-gradient(@dir, @color-stops); // Firefox 3.6+
            background-image: -moz-repeating-linear-gradient(@standard-direction, @color-stops); // Firefox 10+
            background-image: -o-repeating-linear-gradient(@standard-direction, @color-stops); // Opera 11.10+
        }
        .output(...) {
            background-image: repeating-linear-gradient(@standard-direction, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.10+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output() when (@is-standard-side-or-corner) {
        @old-direction: ~`"@{dir}".replace(/^to\s+/, "").replace("top", "b#ottom").replace("right", "l#eft").replace("bottom", "t#op").replace("left", "r#ight").replace(/#/g, "")`;
        .output(false) {
            background-image: -webkit-repeating-linear-gradient(@old-direction, @color-stops); // Chrome 10+
            background-image: -moz-repeating-linear-gradient(@old-direction, @color-stops); // Firefox 3.6+
            background-image: -moz-repeating-linear-gradient(@dir, @color-stops); // Firefox 10+
            background-image: -o-repeating-linear-gradient(@dir, @color-stops); // Opera 11.10+
        }
        .output(...) {
            background-image: repeating-linear-gradient(@dir, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.10+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output() when not (@is-old-side-or-corner) and not (@is-standard-side-or-corner) {
        .output(false) {
            background-image: -webkit-repeating-linear-gradient(mod(abs(convert(@direction, deg) - 450), 360), @color-stops); // Chrome 10+
            background-image: -moz-repeating-linear-gradient(mod(abs(convert(@direction, deg) - 450), 360), @color-stops); // Firefox 3.6+
            background-image: -o-repeating-linear-gradient(mod(abs(convert(@direction, deg) - 450), 360), @color-stops); // Opera 11.10+
        }
        .output(...) {
            background-image: repeating-linear-gradient(@direction, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.10+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output();
}

// General radial gradient (without size in specific dimensions)
.radial-gradient(@shape, @color-stop...) {
    @shape-string: ~"@{shape}";
    @position: ~`(function() { var pos = /(?:^|\s)at\s+(\S+)(?:\s+(\S+)\s*$)?/g.exec("@{shape-string}"); return pos? (pos[2]? pos[1] + ' ' + pos[2] : pos[1]) : 'false'; })()`;
    @contour-and-size: ~`(function() { var cs = /^(circle|ellipse|(?:(?:circle|ellipse)\s+)?(?:closest|farthest)-(?:corner|side))(?=$|\s+at)/.exec("@{shape-string}"); return cs? cs[1] : 'false'; })()`;
    @color-stops: ~`"@{color-stop}".replace(/[\[\]]/g, "")`;

    .output() when not (@position = false) and (@contour-and-size = false) {
        .output(false) {
            background-image: -webkit-radial-gradient(@position, @color-stops); // Chrome 10+
            background-image: -moz-radial-gradient(@position, @color-stops); // Firefox 3.6+
            background-image: -o-radial-gradient(@position, @color-stops); // Opera 11.60+
        }
        .output(...) {
            background-image: radial-gradient(@shape, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.10+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output() when not (@contour-and-size = false) and (@position = false) {
        .output(false) {
            background-image: -webkit-radial-gradient(@contour-and-size, @color-stops); // Chrome 10+
            background-image: -moz-radial-gradient(@contour-and-size, @color-stops); // Firefox 3.6+
            background-image: -o-radial-gradient(@contour-and-size, @color-stops); // Opera 11.60+
        }
        .output(...) {
            background-image: radial-gradient(@shape, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.10+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output() when not (@position = false) and not (@contour-and-size = false) {
        .output(false) {
            background-image: -webkit-radial-gradient(@position, @contour-and-size, @color-stops); // Chrome 10+
            background-image: -moz-radial-gradient(@position, @contour-and-size, @color-stops);
            background-image: -o-radial-gradient(@position, @contour-and-size, @color-stops); // Opera 11.60+
        }
        .output(...) {
            background-image: radial-gradient(@shape, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.10+, IE 10+
        }
        .output(@use-autoprefixer);
    } // Standard, IE10+
    .output() when (@position = false) and (@contour-and-size = false) {
        .output(false) {
            background-image: -webkit-radial-gradient(@shape, @color-stops); // Chrome 10+
            background-image: -moz-radial-gradient(@shape, @color-stops); // Firefox 3.6+
            background-image: -o-radial-gradient(@shape, @color-stops); // Opera 11.60+
        }
        .output(...) {
            background-image: radial-gradient(circle, @shape, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.10+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output();
}

// General repeating radial gradient (without size in specific dimensions)
.repeating-radial-gradient(@shape, @color-stop...) {
    @shape-string: ~"@{shape}";
    @position: ~`(function() { var pos = /(?:^|\s)at\s+(\S+)(?:\s+(\S+)\s*$)?/g.exec("@{shape-string}"); return pos? (pos[2]? pos[1] + ' ' + pos[2] : pos[1]) : 'false'; })()`;
    @contour-and-size: ~`(function() { var cs = /^(circle|ellipse|(?:(?:circle|ellipse)\s+)?(?:closest|farthest)-(?:corner|side))(?=$|\s+at)/.exec("@{shape-string}"); return cs? cs[1] : 'false'; })()`;
    @color-stops: ~`"@{color-stop}".replace(/[\[\]]/g, "")`;

    .output() when not (@position = false) and (@contour-and-size = false) {
        .output(false) {
            background-image: -webkit-repeating-radial-gradient(@position, @color-stops); // Chrome 10+
            background-image: -moz-repeating-radial-gradient(@position, @color-stops); // Firefox 3.6+
            background-image: -o-repeating-radial-gradient(@position, @color-stops); // Opera 12+
        }
        .output(...) {
            background-image: repeating-radial-gradient(@shape, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.50+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output() when not (@contour-and-size = false) and (@position = false) {
        .output(false) {
            background-image: -webkit-repeating-radial-gradient(@contour-and-size, @color-stops); // Chrome 10+
            background-image: -moz-repeating-radial-gradient(@contour-and-size, @color-stops); // Firefox 3.6+
            background-image: -o-repeating-radial-gradient(@contour-and-size, @color-stops); // Opera 12+
        }
        .output(...) {
            background-image: repeating-radial-gradient(@shape, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.50+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output() when not (@position = false) and not (@contour-and-size = false) {
        .output(false) {
            background-image: -webkit-repeating-radial-gradient(@position, @contour-and-size, @color-stops); // Chrome 10+
            background-image: -moz-repeating-radial-gradient(@position, @contour-and-size, @color-stops); // Firefox 3.6+
            background-image: -o-repeating-radial-gradient(@position, @contour-and-size, @color-stops); // Opera 12+
        }
        .output(...) {
            background-image: repeating-radial-gradient(@shape, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.50+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output() when (@position = false) and (@contour-and-size = false) {
        .output(false) {
            background-image: -webkit-repeating-radial-gradient(@shape, @color-stops); // Chrome 10+
            background-image: -moz-repeating-radial-gradient(@shape, @color-stops); // Firefox 3.6+
            background-image: -o-repeating-radial-gradient(@shape, @color-stops); // Opera 12+
        }
        .output(...) {
            background-image: repeating-radial-gradient(circle, @shape, @color-stops); // Chrome 26+, Firefox 16+, Opera 12.50+, IE 10+
        }
        .output(@use-autoprefixer);
    }
    .output();
}


//
// Extended display property values

.display(@display:flex) when (@display=flex) {
    display: -webkit-flex;
    display: -ms-flexbox;
    display: flex;
}
.display(@display:inline-flex) when (@display=inline-flex) {
    display: -webkit-inline-flex;
    display: -ms-inline-flexbox;
    display: inline-flex;
}
.display(@display:box) when (@display=box)  {
    display: -webkit-box;
    display: -moz-box;
}
.display(@display:inline-box) when (@display=inline-box)  {
    display: -webkit-inline-box;
    display: -moz-inline-box;
}
.display(@display) when not (@display = flex)
                    and not (@display = inline-flex)
                    and not (@display = box)
                    and not (@display = inline-box) {
    display: @display;
}


//
// Flexible Box Layout
//
// IE 10 support: http://msdn.microsoft.com/en-us/library/ie/hh673531%28v=vs.85%29.aspx
// IE 11 update: http://msdn.microsoft.com/en-us/library/ie/dn265027%28v=vs.85%29.aspx

.flex-direction(@direction) when not (@use-autoprefixer) {
    -webkit-flex-direction: @direction;
        -ms-flex-direction: @direction;
            flex-direction: @direction;
}
.flex-direction(@direction) when (@use-autoprefixer) {
    flex-direction: @direction;
}

.flex-wrap(@wrap) when not (@use-autoprefixer) {
    -webkit-flex-wrap: @wrap;
        -ms-flex-wrap: @wrap;
            flex-wrap: @wrap;
}
.flex-wrap(@wrap) when (@use-autoprefixer) {
    flex-wrap: @wrap;
}

.flex-flow(@flow) when not (@use-autoprefixer) {
    -webkit-flex-flow: @flow;
        -ms-flex-flow: @flow;
            flex-flow: @flow;
}
.flex-flow(@flow) when (@use-autoprefixer) {
    flex-flow: @flow;
}

.order(@order) when not (@use-autoprefixer) {
    -ms-flex-order: @order;
     -webkit-order: @order;
             order: @order;
}
.order(@order) when (@use-autoprefixer) {
    order: @order;
}

.flex(@flex) when not (@use-autoprefixer) {
    -webkit-flex: @flex;
        -ms-flex: @flex;
            flex: @flex;
}
.flex(@flex) when (@use-autoprefixer) {
    flex: @flex;
}

.flex-grow(@flex) when not (@use-autoprefixer) {
    -webkit-flex-grow: @flex;
    -ms-flex-positive: @flex;
            flex-grow: @flex;
}
.flex-grow(@flex) when (@use-autoprefixer) {
    flex-grow: @flex;
}

.flex-shrink(@flex) when not (@use-autoprefixer) {
    -webkit-flex-shrink: @flex;
      -ms-flex-negative: @flex;
            flex-shrink: @flex;
}
.flex-shrink(@flex) when (@use-autoprefixer) {
    flex-shrink: @flex;
}

.flex-basis(@size) when not (@use-autoprefixer) {
    -ms-flex-preferred-size: @size;
         -webkit-flex-basis: @size;
                 flex-basis: @size;
}
.flex-basis(@size) when (@use-autoprefixer) {
    flex-basis: @size;
}

.justify-content(@align) when not (@use-autoprefixer) {
    @flex-pack: ~`"@{align}".replace(/flex-/ig, "").replace(/space-between/ig, "justify").replace(/space-around/ig, "distribute")`;
    -ms-flex-pack: @flex-pack;
    -webkit-justify-content: @align;
            justify-content: @align;
}
.justify-content(@align) when (@use-autoprefixer) {
    justify-content: @align;
}

.align-items(@align) when not (@use-autoprefixer) {
    @flex-align: ~`"@{align}".replace(/flex-/ig, "")`;
    -ms-flex-align: @flex-align;
    -webkit-align-items: @align;
            align-items: @align;
}
.align-items(@align) when (@use-autoprefixer) {
    align-items: @align;
}

.align-self(@align) when not (@use-autoprefixer) {
    @flex-align: ~`"@{align}".replace(/flex-/ig, "")`;
    -ms-flex-item-align: @flex-align;
     -webkit-align-self: @align;
             align-self: @align;
}
.align-self(@align) when (@use-autoprefixer) {
    align-self: @align;
}

.align-content(@align) when not (@use-autoprefixer) {
    @flex-line-pack: ~`"@{align}".replace(/flex-/ig, "").replace(/space-between/ig, "justify").replace(/space-around/ig, "distribute")`;
    -ms-flex-line-pack: @flex-line-pack;
    -webkit-align-content: @align;
            align-content: @align;
}
.align-content(@align) when (@use-autoprefixer) {
    align-content: @align;
}

//
// Old Flexible Box Layout
// not affected by `@use-autoprefixer` because Autoprefixer doesn't deal with `box-*` syntax.
.box-orient(@orient) {
    -webkit-box-orient: @orient;
       -moz-box-orient: @orient;
}

.box-direction(@direction) {
    -webkit-box-direction: @direction;
       -moz-box-direction: @direction;
}

.box-ordinal-group(@group) {
    -webkit-box-ordinal-group: @group;
       -moz-box-ordinal-group: @group;
}

.box-flex-group(@group) {
    -webkit-box-flex-group: @group;
       -moz-box-flex-group: @group;
}

.box-flex(@flex) {
    -webkit-box-flex: @flex;
       -moz-box-flex: @flex;
}

.box-align(@align) {
    -webkit-box-align: @align;
       -moz-box-align: @align;
}

.box-pack(@align) {
    -webkit-box-pack: @align;
       -moz-box-pack: @align;
}

// box-lines are omitted because no browser did implement it
