Gulpfile sass + livereload + autoprefixer

gulpfile.js

'use strict';

var gulp = require('gulp'),
    sass = require('gulp-sass'),
    livereload = require('gulp-livereload'),
    autoprefixer = require('gulp-autoprefixer');

livereload({ start: true });

gulp.task('sass', function () {
  gulp.src('scss/**/*.scss')
    .pipe(sass().on('error', sass.logError))
    .pipe(autoprefixer({
      browsers: ['last 2 versions'],
      cascade: false
    }))
    .pipe(gulp.dest('css'))
    .pipe(livereload());
});

gulp.task('sass:watch', function () {
  livereload.listen();
  gulp.watch('scss/**/*.scss', ['sass']);
});