The styles and scripts for the outline renderer were included with the rendered outline itself. This meant that if you wanted to override the styles you had to include the <style> section in the outline. This could have been done with a macro, but that's too much work, and requires you to do it in every outline.
Instead, I'm moving the styles into my global stylesheet. Since this is included right after the Bootstrap Toolkit, and before everything else, there are many opportunities to override the styles.
Before testing this, quit and relaunch the OPML Editor on the server. It's caching old outline renderings, so when you think you're testing the new code, you're not. Relaunching clears the cache.
There's an unused script called expandCollapse in worldOutlineSuite.data.templates.outline. Removed it.
Re DJ's request, this is not easy, not something to attempt with all these other changes. First let's see if these get through without breakage, and look at this again.