Adding a character before all headings

Hi all

I’d like to add a character (|) before each heading on my site.
e.g. | Gain Perspective

Is there code I can add to the h tags to ensure the | comes first? Preferably slightly to the left, so that the heading text is still aligned to the body.

I would also like to use it for each bullet point.

Any help would be gratefully received!

Thanks 🙂