feat(module): add theme.defaultVariants option (#4400)

docs/content/1.getting-started/2.installation/1.nuxt.md

@@ -225,6 +225,27 @@ export default defineNuxtConfig({
 This option adds the `transition-colors` class on components with hover or active states.
 ::
 
+### `theme.defaultVariants` :badge{label="Soon" class="align-text-top"}
+
+Use the `theme.defaultVariants` option to override the default `color` and `size` variants for components.
+
+- Default: `{ color: 'primary', size: 'md' }`{lang="ts-type"}
+
+```ts [nuxt.config.ts]
+export default defineNuxtConfig({
+  modules: ['@nuxt/ui'],
+  css: ['~/assets/css/main.css'],
+  ui: {
+    theme: {
+      defaultVariants: {
+        color: 'neutral',
+        size: 'sm'
+      }
+    }
+  }
+})
+```
+
 ## Continuous Releases
 
 Nuxt UI uses [pkg.pr.new](https://github.com/stackblitz-labs/pkg.pr.new) for continuous preview releases, providing developers with instant access to the latest features and bug fixes without waiting for official releases.