///
/// Mixin for setting box-sizing to border-box.
///
@mixin sizing--border {
    box-sizing: border-box;
    -moz-box-sizing: border-box;
    -ms-box-sizing: border-box;
    -webkit-box-sizing: border-box;
}

///
/// Mixin for setting box-sizing to content-box.
///
@mixin sizing--content {
    box-sizing: content-box;
    -moz-box-sizing: content-box;
    -ms-box-sizing: content-box;
    -webkit-box-sizing: content-box;
}

///
/// Mixin for setting box-sizing to padding-box.
///
@mixin sizing--padding {
    box-sizing: padding-box;
    -moz-box-sizing: padding-box;
    -ms-box-sizing: padding-box;
    -webkit-box-sizing: padding-box;
}