Changing the Fusion Theme to a Custom One

Summary:

Hi all,

How can we change the fusion theme only with a transparent logo added to it without changing the current default theme or other themes, retaining the default theme setups but still changing it to another custom one with a different logo to the theme by retaining what both the navigation menu and the springboard icons look like in the default theme? Also, how to change the black ribbon to transparent or a white one entirely, starting from the hamburger menu option through the general settings open on the home screen? I am not able to change it either through the