cnpm install -g gulp

cnpm install -save-dev gulp

var gulp = require(‘gulp‘);var browserSync = require(‘browser-sync‘);var reload = browserSync.reload;

gulp.task(‘serve‘, function() {  browserSync({    server: {      baseDir: ‘app‘    }  });  gulp.watch([‘*.html‘, ‘styles/**/*.css‘, ‘scripts/**/*.js‘], {cwd: ‘app‘}, reload);});

gulpfile.jsapp/  styles/    main.css  scripts/    main.js  index.html

cnpm install -save-dev  browser-sync

http://www.gulpjs.com.cn/docs/recipes/server-with-livereload-and-css-injection/