task scss

scss.js

/**
  подключаемые плагины:
 
  npm i
  gulp
  gulp-load-plugins
  gulp-plumber
  gulp-notify
  gulp-sourcemaps
  gulp-sass
  gulp-autoprefixer
  gulp-cssnano
  gulp-rename
  
  -D
  
 */
var g = require("gulp"),
    p = require("gulp-load-plugins")(),
    u = {
        scss: "app/scss/main.scss",
        css: "app/css"
    };

g.task("css", function() {
    g.src(u.scss)
        .pipe(p.plumber({
            errorHandler: p.notify.onError(function(err) {
                return {
                    title: 'task css',
                    message: err.message
                }
            })
        }))
        .pipe(p.sourcemaps.init())
        .pipe(p.sass())
        .pipe(p.autoprefixer())
        .pipe(p.cssnano())
        .pipe(p.rename("main.min.css"))
        .pipe(p.sourcemaps.write())
        .pipe(g.dest(u.css));
});