docs: add docs for style query for badges (npmx-dev#1571)

Author: btea

docs/content/2.guide/1.features.md

@@ -195,3 +195,10 @@ When set to `true`, this parameter replaces the static category label (like "ver
 | ------------- | -------------------- | ---------------- |
 | **Version**   | `version \| 3.12.0`  | `nuxt \| 3.12.0` |
 | **Downloads** | `downloads/mo \| 2M` | `lodash \| 2M`   |
+
+##### `style`
+
+Overrides the default badge appearance. Pass `shieldsio` to use the shields.io-compatible style.
+
+- **Default**: `default`
+- **Usage**: `?style=shieldsio`