remove thin line

Install this plugin (or any other that does the same).
https://www.ads-software.com/plugins/simple-custom-css/

Use this code in it.

.site-extra { border-top: none; }

Hi ajiewp,

The code given by paulwpxp is absolutely correct but I would like to reccomend you another plugin for custom css and also will suggest you to try child theme instead of these plugins if possible, cause this will give you loads of flexibility.

Thanks