While you have simple directories for customization code in ConfigBox for Joomla and Wordpress, in Magento 2 it takes requires a simple Magento module to place this code in (Magento code architecture reasons).
To customize your ConfigBox for Magento installation, you use this module and install it install the module below in the /app/code location/. The module name is Rovexo/ConfigboxCustomizations and there is a subdirectory for your custom assets (like images, stylesheets, javascript) and customization code (custom language files, controllers, models, views etc).
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