Why doesn't npm install work under Ubuntu 16.04?

Question

ubuntu

npm version
5.5.1,
node.js 9.0.0 Package.json
content

{
  "name": "sass.loc",
  "version": "1.0.0",
  "description": "",
  "main": "index.js",
  "scripts": {
    "test": "echo \"Error: no test specified\" && exit 1"
  },
  "author": "",
  "license": "ISC",
  "devDependencies": {
    "browser-sync": "^2.18.13",
    "gulp": "^3.9.1",
    "gulp-autoprefixer": "^4.0.0",
    "gulp-clean-css": "^3.9.0",
    "gulp-concat": "^2.6.1",
    "gulp-ftp": "^1.1.0",
    "gulp-json-transform": "^0.4.5",
    "gulp-postcss": "^7.0.0",
    "gulp-rigger": "^0.5.8",
    "gulp-sass": "^3.1.0",
    "gulp-sourcemaps": "^2.6.1",
    "gulp-uglify": "^3.0.0",
    "gulp-watch": "^4.3.11"
  }
}

Mistake

sudo npm install                                                                                                          ──(Чт,ноя02)─┘

> [email protected] install /var/www/sass.loc/node_modules/node-sass
> node scripts/install.js

Unable to save binary /var/www/sass.loc/node_modules/node-sass/vendor/linux-x64-59 : { Error: EACCES: permission denied, mkdir '/var/www/sass.loc/node_modules/node-sass/vendor'
    at Object.fs.mkdirSync (fs.js:905:18)
    at sync (/var/www/sass.loc/node_modules/node-sass/node_modules/mkdirp/index.js:71:13)
    at Function.sync (/var/www/sass.loc/node_modules/node-sass/node_modules/mkdirp/index.js:77:24)
    at checkAndDownloadBinary (/var/www/sass.loc/node_modules/node-sass/scripts/install.js:111:11)
    at Object.<anonymous> (/var/www/sass.loc/node_modules/node-sass/scripts/install.js:154:1)
    at Module._compile (module.js:641:30)
    at Object.Module._extensions..js (module.js:652:10)
    at Module.load (module.js:560:32)
    at tryModuleLoad (module.js:503:12)
    at Function.Module._load (module.js:495:3)
  errno: -13,
  code: 'EACCES',
  syscall: 'mkdir',
  path: '/var/www/sass.loc/node_modules/node-sass/vendor' }

> [email protected] postinstall /var/www/sass.loc/node_modules/node-sass
> node scripts/build.js

I don't even know what to think?

Answer 1

I solved the problem only by completely removing node.js and reinstalling it via nvm.
Who needs here is a link to the article https://losst.ru/ustanovka-node-js-ubuntu-16-04.
The article describes 4 methods, I chose the first one, as recommended.
Thank you for responding.

Answer 2

cannot create folder /var/www/sass.loc/node_modules/node-sass/vendor
check permissions

Answer 3

No permission to write to the folder. The path is specified in path.
sudoonly needed when installing global packages.