Gulpfile critical

Gulpfile-pt3.js

// Create and process critical CSS file to be included in head
gulp.task('build:styles:critical', function() {
  return sass(paths.sassFiles + '/critical.scss', {
    style: 'compressed',
    trace: true,
    loadPath: [paths.sassFiles]
  }).pipe(postcss([ autoprefixer({ browsers: ['last 2 versions'] }), cssnano()]))
    .pipe(gulp.dest('_includes'))
    .on('error', gutil.log);
});
// Build all styles
gulp.task('build:styles', ['build:styles:main', 'build:styles:critical']);