Header Custom Code

Site URL: https://sparkotechengineering.squarespace.com/

Help Please!

I want to make the drop down of my categories have some space or borders. Tried to code it but i can't make it work. 

@rwp It actually worked! One more thing what code to use if i'm going to put borders in it

What do you want borders around? Each item or the whole folder?

each item please

.header-nav-folder-content {
    padding: 0px !important;
}

.header-nav-folder-item {
    padding: 5px;
    border-width: 1px 1px 0px 1px;
    border-style: solid;
    border-color: black;
}

.header-nav-folder-content:last-child {
    border-bottom: 1px solid black !important;
}

.header-nav-folder-item:hover {
    background-color: #dddddd;
}

The last block will change the background color on mouse over too, you can change the color or leave it out if you don't like it.

Thanks a lot!