Theme options
From LimeSurvey Manual
The template options functionalities are present in LimeSurvey 3.0+. It offers a set of various options that allows you to quickly and easily change the templates-related settings of the surveys that belong to the same survey group:
The Inherit everything functionality lets you decide whether you want the survey group to inherit everything or not from the parent survey group theme.
If you do not want this to happen, select "No". The following options will show up:
Bootswatch themes can be used to quickly edit your templates. Basically, bootswatch is a collection of themed swatches which can be freely downloaded and dropped into your Bootstrap site. Some of these themes are already included into your LimeSurvey installation and they can be selected from the Bootswatch theme drop-down list.
If you want to tweak more a survey group template options, click on the advanced option tab (recommended for the advanced users only):