Worked like a charm. Thank you very much.
Enjoy your coffee 
Topic summary
A user sought help creating rounded corners for the registration page box on their Shopify store, providing a screenshot and URL as reference.
Solution provided:
- Navigate to Online Store → Edit Code
- Locate the theme.liquid file
- Insert custom CSS code just above the closing tag
- The CSS targets registration form elements and applies border-radius styling
Outcome: The solution successfully resolved the issue. The user confirmed it “worked like a charm” and thanked the helper.