Update README.md

Author: ananttripathi

README.md

@@ -56,7 +56,7 @@ npm install
 npm run dev
 ```
 
-Open [https://ananttripathi.github.io/code-differentiator/](https://ananttripathi.github.io/code-differentiator/).
+Open [http://localhost:5173](http://localhost:5173).
 
 ```bash
 npm run build    # production build → dist/