Tailwind CSS Classes Not Applying or Conflicting

1. tailwind.config.js content paths don't include component files
2. Using arbitrary class names outside content scope
3. CSS !important declarations overriding Tailwind utilities
4. Tailwind CSS not imported in main.css
5. Template files not scanned due to wrong file extension

Verify tailwind.config.js includes all template files:

export default {
  content: [
    './index.html',
    './src/**/*.{js,jsx,ts,tsx}'
  ]
}

Import in main.css:

@tailwind base;
@tailwind components;
@tailwind utilities;

Avoid !important in custom CSS that conflicts with utilities.