获取源地图与Gulp合作

Question

使用Gulp获取源图的任何帮助？这是我第一个使用Gulp和SASS的项目，我已经设置好了，我发现无法使用缩小的css使用Developer工具进行调试。

var gulp = require('gulp');
var sass = require('gulp-sass');
var browserSync = require('browser-sync').create();
var header = require('gulp-header');
var cleanCSS = require('gulp-clean-css');
var rename = require("gulp-rename");
var uglify = require('gulp-uglify');
var pkg = require('./package.json');
var sourcemaps = require('source-map');

// Compiles SCSS files from /scss into /css
gulp.task('sass', function() {
  return gulp.src('scss/creative.scss')
    .pipe(sourcemaps.init())
    .pipe(sass())
    .pipe(header(banner, {
      pkg: pkg
    }))
    .pipe(sourcemaps.write())
    .pipe(gulp.dest('css'))
    .pipe(browserSync.reload({
      stream: true
    }))
});