Hi @xertz please describe your use-case much more in more detail. Are you embedding in a flask or other webapp? In a jupyter notebook? Is this just standalone HTML output? Center within the page? within a div? Widgets and plots centered individually? Together as a group? Screenshots or drawings would be very helpful.
Is this a Bokeh server application that you run with bokeh serve ? If so, that is not standalone HTML (it requires and depends on the Bokeh server being running). Regardless you will have to use a custom Jinja template. As soon as I know if this is standalone HTML or a Bokeh server application, I can point you more directly to the relevant documentation.