Working with the Web Resource Repository 
The Web Resource Repository provides a single storage location for all your portal application resources and branding resources. It enables you to upload, download, view, and modify these resources, without the need to redeploy applications to see the results of your modifications.
You can reference the resources from multiple applications in different ways. For example, you can use the Web Resource Repository public APIs to reference resources from code, add references to resources in other Web resources, such as from a .css file, and use the Icon URI parameter to reference resources from portal components.
Caution
Do not delete the Application Branding folder.
For more information, see:
Note
The resources (.less files, .css files, and image files) that are used by the tablet and smartphone framework pages are also stored in the Web Resource Repository. You can modify these resources to brand your portal for mobile devices. For more information, see Branding Portal on Device.