Injecting SCSS variables

I want compile different css files based on different sass variables.

Im trying to use Gulp to achieve this

gulp.task('var 1', function() {
    gulp.src(['styles/vars/var1.scss','styles/fa/*.scss', 'styles/shared/*.scss','styles/*.scss'])
        .pipe(sass().on('error', sass.logError))
        .pipe(concat('clientWithVar1.css'))
        .pipe(gulp.dest('./public/'))
});

It doesnt seem to work and im getting a Sass error that a variable doesnt exist.

How can i achieve this? Any help is appreciated

via Zolve