How to put between forum category's line's in stead of the standard grey line
 

Hi there,

Im new to all this so please hold in mind that I need help in a way that a newbi would understand.

Im trying to put lines between the category's in the forum but I can't figure out how. The default skin (vBulletin 5 connect) has this standard grey big line, I would like to change that into a thin black line.

Also, I have a banner made, I tried to put the code in it and it worked, but I can't get the Advanced Search option in it, in stead the search option becomes bellow the banner. I would like to get the search option in the banner itself on the right side.

Thanks.