@mixin hover {
    @if $enable-hover-media-query {
        // See Media Queries Level 4: http://drafts.csswg.org/mediaqueries/#hover
        // Currently shimmed by https://github.com/twbs/mq4-hover-shim
        @media (hover: hover) {
            &:hover {
                @content
            }
        }
    } @else {
        &:hover {
            @content
        }
    }
}

@mixin hover-focus {
    @if $enable-hover-media-query {
        &:focus {
            @content
        }
        @include hover {
            @content
        }
    } @else {
        &:focus,
        &:hover {
            @content
        }
    }
}

@mixin plain-hover-focus {
    @if $enable-hover-media-query {
        &,
        &:focus {
            @content
        }
        @include hover {
            @content
        }
    } @else {
        &,
        &:focus,
        &:hover {
            @content
        }
    }
}

@mixin hover-focus-active {
    @if $enable-hover-media-query {
        &:focus,
        &:active {
            @content
        }
        @include hover {
            @content
        }
    } @else {
        &:focus,
        &:active,
        &:hover {
            @content
        }
    }
}