What if I don't want to use any Custom CSS?

You may remove any Custom CSS module within the layout section by simply deleting the code module. You may also remove any class names applied to modules by going to Module Settings → Advanced → CSS ID and Classes

This may result in a sub-optimal user experience as the design may not look as polished across mobile, tablet and desktop screen sizes. 

See Listing Layout documentation for examples of how designs might not look as polished without the use of Custom CSS.