enhance README

README.md

@@ -102,7 +102,7 @@ func main() {
 > `xybor-x/enum` supports three enum types: **Basic enum** for simplicity, **Wrap enum** for enhanced functionality, and **Safe enum** for strict type safety.
 
 | Features                                       | Basic enum ([#][1]) | Wrap enum ([#][2]) | Safe enum ([#][3]) |
-| ---------------------------------------------- | ------------------- | ------------------ | ------------------ |
+| :--------------------------------------------- | ------------------- | ------------------ | ------------------ |
 | **Underlying type required**                   | **No**              | Yes                | Yes                |
 | **Built-in methods**                           | No                  | **Yes**            | **Yes**            |
 | **Constant enum** ([#][5])                     | **Yes**             | **Yes**            | No                 |