clean_css

https://www.npmjs.com/package/gulp-clean-css

Очищает css от пробелов

npm install gulp-clean-css

cleanCSS

cleanCSS([options][, callback])

const gulp = require('gulp');
const cleanCSS = require('gulp-clean-css');

gulp.task('minify-css', () => {
    gulp.src('styles/*.css')
        .pipe(cleanCSS({
            compatibility: 'ie8',
            // уровень сжатия
            level: 2
        }))
        .pipe(gulp.dest('dist'));
});

const gulp = require('gulp');
const cleanCSS = require('gulp-clean-css');

gulp.task('minify-css', () => {
    gulp.src('styles/*.css')
        .pipe(cleanCSS({debug: true}, function(details) {
            console.log(details.name + ': ' + details.stats.originalSize);
            console.log(details.name + ': ' + details.stats.minifiedSize);
        }))
        .pipe(gulp.dest('dist'));
});