title: Nuxt package.json NODE_ENV Invalid setting
body: <p>I have a <code>Nuxt.js</code> project that needs to be released to different environments</p>
  
  <p>package.json</p>
  
  <p><a href="https://i.stack.imgur.com/QRLsc.png" rel="nofollow noreferrer">enter image description here</a></p>
  
  <pre><code>"compile:dev-start": "cross-env NODE_ENV=dev nuxt build &amp;&amp; cross-env NODE_ENV=dev nuxt start",
  "compile:qafc-start": "cross-env NODE_ENV=qafc nuxt build &amp;&amp; cross-env NODE_ENV=qafc nuxt start",
  </code></pre>
  
  <p>But the value obtained by <code>process.env.NODE_ENV</code> is not a dev or qafc value
  But it is production. Is this what is the reason? How can I get dev or qafc?</p>