Change background skin confluence

You don't have writ access to that location.

1. Copy the complete skin to: /storage/.kod/addons
2. Edit the addon.xml file and rename the skin to something else
3. Do the changes you want to do
4. Enable the skin at addons->my addons->look and feel->skins->your skin-name
5. Use the skin by system settings->interface settings->skin->your skin-name

done

Here is a more detailed description on how to modify a skin

thread-6659-post-41919.html#pid41919

Confluence supports a custom background. No need to modify the skin:

Settings > Interface > Skin > Configure Skin > Background Options > Configure custom background > Point to local file somewhere on /storage