Dotted & Dashed Lines

I changed my blog template again, but i’m trying to figure out how to add dividing dashed lines in between my sidebar widgets, and also instead of having a plain rectangular one color bar behind my navigation bar under my header, I would like to have instead two dashed lines on the top and the bottom, like this blog: https://www.hellolucky.com/wordpress/

My blog is https://www.jeanelleechols.com/donaana/

Thanks!