Calling Wordpress peeps … #help

I am using the 2020 template and my HR separator default to this …

Whatever happened to good old plain lines that I can manage with CSS - my only choice as an alternative seems to be a dots … anyone know how I can go back to a simple line that I can style myself?

I have googled but all that I can find is what I know … I am guessing that I need to define it in the bowels of WP somewhere?

My thanks in anticipation.