Respondage plain LS3 theme

This is version 1 (June 28, 2021) of the Respondage theme for LimeSurvey 3. It is a base theme in the sense that is developed to be a theme that can be used as a canvas for further development. But you can also use it right away or adapt it to your needs.

Take care: this is for LimeSurvey 3, not for LimeSurvey 5 or 6!