You can use tw-colors to create a predefined theme p>

   const { createThemes } = require('tw-colors');

   module.exports = {
      content: ['./src/**/*.{astro,html,js,jsx,md,mdx,svelte,ts,tsx,vue}'],
      plugins: [
         createThemes({
            banana: { 
               'primary': 'steelblue',
               'secondary': 'darkblue',
               'brand': '#F3F3F3',
            },
            halloween: { 
               'primary': 'turquoise',
               'secondary': 'tomato',
               'brand': '#4A4A4A',
            },
            darkula: { 
               'primary': '#2A9D8F',
               'secondary': '#E9C46A',
               'brand': '#264653',
            },
         })
      ],
   };

Then apply the theme to the card container

<div class='theme-darkcula'>
    <h2 class='text-primary'>Username</h2>
    <p class='text-secondary'>...</p>
</div>

<div class='theme-halloween'>
    <h2 class='text-primary'>Username</h2>
    <p class='text-secondary'>...</p>
</div>

If subject class names come from API responses, you should safelist them, otherwise tailwind will not generate them, see tailwind documentation for more details