gulpfile.js

var gulp = require('gulp');
var sass = require('gulp-sass');
var sourceMaps = require('gulp-sourcemaps');
var autoprefixer = require('gulp-autoprefixer');
var browserSync = require('browser-sync').create();
var concat = require('gulp-concat');
var foundation = 'node_modules/foundation-sites/';

autoprefixer({
  browsers: ['last 2 versions', 'ie >= 9', 'and_chr >= 2.3']
});

gulp.task('build:sass', function(){
    gulp.src('src/app/scss/style.scss')
        .pipe(sourceMaps.init())
        .pipe(sass({includePaths: [foundation+'scss', 'src/app/scss']}))
        .pipe(sourceMaps.write('.'))
        .pipe(gulp.dest('src/app/css'))
        .pipe(browserSync.reload({
             stream: true
        }));
});

gulp.task('build:prefix', function(){
    gulp.src('src/app/css/style.css')
        .pipe(autoprefixer({
            browsers: ['last 2 versions', 'ie >= 9', 'and_chr >= 2.3'],
            cascade: false
        }))
        .pipe(gulp.dest('src/app/css'));
});

gulp.task('build:js', function(){
    gulp.src([
        foundation+'dist/js/plugins/foundation.core.min.js',
        foundation+'dist/js/plugins/foundation.util.mediaQuery.min.js',
        foundation+'dist/js/plugins/foundation.abide.min.js',
        'src/app/js/scripts.js'
    ])
        .pipe(concat('all.js'))
        .pipe(gulp.dest('src/app/js'))
        .pipe(browserSync.reload({
             stream: true
        }));
});

gulp.task('build', ['build:sass', 'build:prefix', 'build:js']);

gulp.task('watch', ['browserSync', 'build'], function(){
    gulp.watch('src/app/scss/*.scss', ['build:sass','build:prefix']);
    gulp.watch('src/app/*.html', browserSync.reload);
    gulp.watch('src/app/js/scripts.js', ['build:js']);
        // .pipe(browserSync.reload({
        //     stream: true
        // }));
});

gulp.task('browserSync', function(){
    browserSync.init({
        server: {
            baseDir: 'src/app'
        }
    })
})