Using baseurl in patterns

I saw in the default template `{{@root.baseurl}}` so I tried to use it in a pattern to point to icons that I added to the assets directory. Using it here adds an extra `../`. From what I can tell this happens because `@root` is the initial context that the template was executed in. Is there a way to use this in a pattern that I am just not seeing or do I have to hard code the directory levels?

I'm using it like this:
``

and getting
``

when I should get
``