我正在编写CSS Grid教程，但我的问题与CSS Grid无关，而是与package.json有关！我完全按照讲师的指示操作，但当我运行'npm start'时，我收到一条错误消息。我的问题是我的package.json脚本是否过时了（因为技术似乎每周都在变化）还是我在遵循教程时做错了什么？是否有一个专门的来源，我可以参考，将告诉我，如果代码是过时的？提前谢谢你！
错误消息：
错误：未找到任务：“watch：sass”npm ERR！code ELIFECYCLE npm ERR！errno 1 npm ERR！Project@1.0.0 start：npm-run-all --parallel devserver watch:sass npm错误！退出状态1 npm错误！npm错误！Project@1.0.0启动脚本失败。npm错误！这可能不是npm的问题。上面可能有其他日志输出。
Package.json:

{
  "name": "Project",
  "version": "1.0.0",
  "description": "Project webpage",
  "main": "index.js",
  "scripts": {
    "watch-css": "node-sass sass/main.scss css/style.css -w",
    "devserver": "live-server",
    "start": "npm-run-all --parallel devserver watch:sass",
    "compile:sass": "node-sass sass/main.scss css/style.comp.css",
    "prefix:css": "postcss --use autoprefixer -b 'last 10 versions' css/style.comp.css -o css/style.prefix.css",
    "compress:css": "node-sass css/style.prefix.css css/style.css --output-style compressed",
    "build:css": "npm-run-all compile:sass prefix:css compress:css"
  },
  "author": "Jerrell",
  "license": "ISC",
  "devDependencies": {
    "autoprefixer": "^9.4.3",
    "concat": "^1.0.3",
    "node-sass": "^4.11.0",
    "npm-run-all": "^4.1.5",
    "postcss-cli": "^6.1.0"
  }
}