title: Building CSS with Tailwindcss not working
body: <p>I am pretty new to Tailwind and CSS as a whole and am trying to build this CSS file:</p>
  <pre><code>@tailwind base;
  @tailwind components;
  @tailwind utilities;
  
  .btn{
      @apply rounded-full py-2 px-3 uppercase text-xs font-bold cursor-pointer tracking-wider
  }
  </code></pre>
  <p>With this command</p>
  <pre><code>npm run build-css
  </code></pre>
  <p>But I get this response</p>
  <pre><code>&gt; course@1.0.0 build-css C:\Users\user\Tailwind\project
  &gt; tailwindcss build src/styles.css -o public/styles.css
  
  [deprecation] Running tailwindcss without -i, please provide an input file.
  
  Done in 3220ms.
  </code></pre>
  <p>And nothing happens. How do I specify the input file?</p>