Making Custom theme style the default for all users

I have created a custom theme style in SuiteP that looks good and shows up in the dropdown list for available styles under Profile -> Layout Options, but I cannot seem to figure out how to make that the default style for all users, as all new users and returning users are still defaulted to ‘Day’…is there a way for me to establish my custom style (It is named ‘custom’) as the default?

edit: I used to create and implement the custom sub-theme

Issue solved - Edited themeDef.php in custom folder