Position of submit button

Hi.

Thanks for a nice plugin.

I’m using the default countdown theme.
In the first preview I tried, the submit button is positioned just to the right of the form field to enter the email address on the same.
At some point after entering content, e.g., translations, adding logo, background image, etc., the submit button is suddenly positioned below the email form field.

That position could be fine for us, but since it seems to be designed to be next to the email form field, then the leftmost corners are sharp instead of round.

How can the submit button be positioned correctly again?