Version 3.x uses a modern built-in theme system. For most websites, you should customize the calculator with theme options instead of creating custom PHP theme files.
The recommended workflow is:
- open the calculator
- go to Preview
- choose the theme and adjust the presentation options
- test the result before saving
Theme options currently cover the most common styling needs, including:
- accent color
- font family
- font size
- border radius
- border color
- field layout
- empty price message
About legacy PHP themes
Older versions used PHP theme files, sometimes based on Bootstrap, UIkit, or custom markup. That is no longer the primary rendering model in 3.x.
If you import an old calculator ZIP that referenced a legacy PHP theme, version 3.x maps that theme to the default modern theme instead of restoring the PHP template.
For new projects, the recommended order is:
- theme options
- scoped custom CSS
- developer-level customization with hooks or custom integration code
If you still maintain a legacy PHP theme for historical reasons, keep it under version control and test it carefully after every major plugin update. For legacy-only reference, see Legacy field markup customization.