Typhoon Theme Tailwindcss not accepted

Hi,
I want to change the background color of one of the modular blocks (image) in the Typhoon theme.
So I modify the section classen from bg-white to bg-yellow-300.
Yellow-300 is one of the regular Tailwindcss options. However, it is not turning in the color I want. One would expect that this valid Tailwindcss code would be accepted.
anyone any suggestions?

Regards,
Arjan

You probably need to run npm to update the CSS. Try 'npm run dev' in terminal from within the theme folder - or for more in depth help, have a look here:

https://getgrav.org/premium/typhoon/docs#developing-custom-css