How to run gulp with livereload and opn?

The problem is this, install npm install --save-dev gulp gulp-connect opn prescribed in gulpfile.js but after the call displays gulp gulp: command not found
(did everything according to the video on loftschool) here's the project itself https://github.com/kovaldn/dz-port
my gulpfile.js
var gulp = require("gulp"),
 connect = require("gulp-connect"),
 opn = require("opn");

gulp.task('connect', function() {
connect.server({
 root: 'app',
 livereload: true,
 port: 8888
});
opn('http://localhost:8888');
});

gulp.task('html', function () {
gulp.src('./app/*.html')
.pipe(connect.reload());
});

gulp.task('css', function () {
gulp.src('./app/css/*.css')
.pipe(connect.reload());
});

gulp.task('js', function () {
gulp.src('./app/js/*.js')
.pipe(connect.reload());
});

gulp.task('watch', function () {
 gulp.watch(['./app/*.html'], ['html']);
 gulp.watch(['./app/css/*.css'], ['css']);
 gulp.watch(['./app/js/*.js'], ['js']);
});

gulp.task('default', ['connect', 'watch']);
July 9th 19 at 10:15
2 answers
July 9th 19 at 10:17
Solution
gulp-livereload is not working. Use gulp-refresh.
July 9th 19 at 10:19
Yuzay browser-sync

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