Add support for dark mode

[transitive-bullshit]

Just need to port this over and add it to the demo.

[DaniGuardiola]

Working on this.

For future reference, this seems to be the place where the dark styles are in the original project: https://github.com/lfades/static-tweet/blob/3105e53bce14fa9a8dd004fb9cd66732069c29c9/components/dark-layout/dark.module.css

[leerob]

I was able to make this work with CSS variables, might be worth adding to the README. This is with Tailwind CSS specifically:

@import 'react-static-tweets/styles.css';

.static-tweet {
  margin: 40px auto;
  --tweet-bg-color: theme('colors.white');
  --tweet-font-color: theme('colors.black');
  --tweet-color-gray: theme('colors.neutral.500');
  --tweet-border: 1px solid theme('colors.neutral.200');
  --tweet-border-hover: 1px solid theme('colors.neutral.300');
}

.static-tweet-header-name {
  color: theme('colors.black');
}

@media (prefers-color-scheme: dark) {
  .static-tweet {
    --tweet-bg-color: theme('colors.neutral.900');
    --tweet-font-color: theme('colors.white');
    --tweet-color-gray: theme('colors.neutral.400');
    --tweet-border: 1px solid theme('colors.neutral.800');
    --tweet-border-hover: 1px solid theme('colors.neutral.700');
  }

  .static-tweet-header-name {
    color: theme('colors.white');
  }
}