@mixin linear-gradient( $gradient: null ) {
    @if $gradient and $enable-gradients {
        @if $gradient == none {
            background-image: none
        }
        @else {
            background-image: linear-gradient( $gradient );
        }
    }
}

@mixin striped-gradient( $color: rgba(255,255,255,.15), $angle: 45deg) {
    background-image: linear-gradient($angle, $color 25%, transparent 25%, transparent 50%, $color 50%, $color 75%, transparent 75%, transparent);
}