Extend Survey core theme (vanilla for exemple) , i NEVER talk of Question Theme, and i give ypou the link to Survety theme …

Add in custom.css the line i show you

Add CSS class fifty-fifty to the needed question

Hello Denis

Thank you very much for your help and patience with me.

I finally made it (see attached file).
A small remark, although it is not important for me: the "Help" message is not shown, even if the "Hide tip" button is disabled (Off).

This survey is part of my PhD thesis and I want to send it in September.

Thank you so much again.

Regards

Miguel