In WordPress to remove the divider line between the main content and sidebar area, you need to write the following css in the Customize > Additional CSS section.


@media (min-width: 981px) {
#main-content .container:before {display: none !important;}
}


I found this information from this YouTube video: https://www.youtube.com/watch?v=P0qkHS7Wucc

NOTE: YouTube video example uses DIVI theme. I also use DIVI, therefore I did not test with other type theme, but I’m thinking it should still work. Let me know if you happen to try!