我遇到了这个问题，请帮助我学习React JS，并且我也第一次问了一个关于stackoverflow的问题，请问我是否违反了任何提出问题的协议。
'webpack-dev-server' is not recognized as an internal or external command,
operable program or batch file.
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! reactapp@1.0.0 start: `webpack-dev-server --hot`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the reactapp@1.0.0 start script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.
npm ERR! A complete log of this run can be found in:
npm ERR! C:\Users\-\AppData\Roaming\npm-cache\_logs\2019-07-24T09_22_22_523Z-debug.log
我尝试安装npm install --save-dev babel-plugin-styled-components来解决问题，就像我在YT视频中看到的那样，但是没有任何反应。
请帮助我解决这个问题，谢谢。