Some classes of tailwindcss are not working in next.js specially spacing classes

[umair-sajjad]

Some classes of tailwindcss are not working in next.js specially spacing classes.

"dependencies": {
    "@tailwindcss/postcss": "^4.0.14",
    "next": "15.2.2",
    "postcss": "^8.5.3",
    "react": "^19.0.0",
    "react-dom": "^19.0.0",
    "tailwindcss": "^4.0.14"
  }

postcss.config.mjs:

const config = {
    plugins: {
      "@tailwindcss/postcss": {},
    },
  };
export default config;

global.css:

@import "tailwindcss";
* {
  box-sizing: border-box;
  padding: 0;
  margin: 0;
}

Kindly tell me why this is happening and what is solution?

[wongjn]

It is happening because the following rule is removing the margin and padding:

* {
  box-sizing: border-box;
  padding: 0;
  margin: 0;
}

Consider removing this rule altogether. Preflight already has this CSS for you.

[umair-sajjad]

great! it worked...