Demo: https://atomic.kontentdesign.com
Atomic is a "skeleton" template for Joomla 3 and 4. It's a slim template with the ability to enable/disable the various libraries in Joomla or add your own. It's for Joomla users who want a basic starting point for creating their own custom Joomla template.
It includes the following frameworks and each is customizable:
-Bootstrap 4
-jQuery
-Google Fonts
-Font Awesome icons
You can load all of these locally from your server or from their respective CDNs. Atomic also has the following module positions predefined:
Page header
Top navigation
Above body
Left body | Right body
Below body
Footer
If you are moving from the Protostar template, just enable the setting to activate the positions and it'll be a seamless switch.
Atomic also contains ways you can add your own custom CSS using a file or directly into the configuration. You can also add custom page code and your Google Analytics ID.