Generated CSS works running with npm, but not embedded in Magento

[rafabandero]

I've changed primary background colors in tailwind.config.js and it works properly while runing the app through npm, but not embedded in Magento.

Preconditions (*)

1. Magento 2.4.6-p2
2. hyva-themes/magento2-react-checkout 1.1.3
3. node v16.20.2 and npm 8.19.4

Steps to reproduce (*)

1. Change primary background color in reactapp/tailwind.config.js

      backgroundColor: {
        primary: {
          lighter: '#e8697f',
          DEFAULT: '#ea0029',
          darker: '#a7001f',
        },
        secondary: {
          lighter: colors.blue['100'],
          DEFAULT: colors.blue['200'],
          darker: colors.blue['300'],
        },
        container: {
          lighter: '#ffffff',
          DEFAULT: '#fafafa',
          darker: '#f5f5f5',
        },
      },

2. Execute npm install
3. Execute npm run build
4. In magento checkout the CSS changes doesn't get applied:

5. Executing npm run start the changes works properly:

** I figured out that the new style classes I've included in reactapp/src/tailwindcss/components/theming.css are not accessible in Magento too. Tried to redeploy static content but nothing changes.