If you want to customize a theme to make any modification in it, you must take care about few essentials steps.

By default in the module you have few themes preinstalled :

If you are using one of this theme in your

Module >> Styles Options >> Theme (dropdown list)

and if you want to modify it, then you must follow these steps :

  1. Copy / Paste the existing theme folder that you want to modify
  2. Rename the folder to the name you want (without space or any special chararcter)
  3. Go in the Module >> Style Options >> Theme : select the new folder that you have created

That's it, you have created a custom theme where you can make any modifications.

 

New theme folder named "mytheme"
Module styles options to select the new theme
Why do I need this

If you don't follow these steps and if you customize a preinstalled theme, all your modifications will be lost during the next update of the module that will copy the themes again.