Saving template in backend reset css files

Hello,
When I edit parameters in a template (/administrator/index.php?option=com_flexicontent&view=templates) and save, it reset my css files (by default) of that template.
Is there a way to fix it ?

Thank you.

Hello

i think you missed that some CSS files have respective LESS files

So only edit CSS files that do not have respective LESS files (LESS code = CSS code plus variables, nesting, etc)

For modifying the CSS files that are compiled from a LESS files , edit the LESS file

Thank you ggppdk, it works good now