feat(embed): Add support for dark mode (#6912)

* feat(embed): Support dark mode (wip)

* finishing up the implementation

* fix tailwind color selector

* tweak design

* refactor: unify types

* fix

* fix english grammar

* refactor: unify types

* tweak design

* remove the customization part

bskyembed/tailwind.config.cjs

@@ -1,11 +1,19 @@
 /** @type {import('tailwindcss').Config} */
 module.exports = {
   content: ['./index.html', './src/**/*.{js,ts,jsx,tsx}'],
+  darkMode: ['variant', [
+    '&:is(.dark *):not(:is(.dark .light *))',
+  ]],
   theme: {
     extend: {
       colors: {
         brand: 'rgb(10,122,255)',
+        brandLighten: 'rgb(32,139,254)',
         textLight: 'rgb(66,87,108)',
+        textDimmed: 'rgb(174,187,201)',
+        dimmedBgLighten: 'rgb(30,41,54)',
+        dimmedBg: 'rgb(22,30,39)',
+        dimmedBgDarken: 'rgb(18,25,32)',
       },
     },
   },