Hi Nicole,
Custom CSS must be used for that task:
@media screen and (min-height: 550px) {
body.predefined-header1 #sp-header .sp-megamenu-wrapper {margin-top: 50px;}
body.predefined-header1 #sp-header .sp-megamenu-wrapper .sp-megamenu-parent > li,
body.predefined-header1 #sp-header .sp-megamenu-wrapper .sp-megamenu-parent > li:not(:last-child)
{margin-bottom: 10px;}
}
In Template Options > Custom Code > Custom CSS
https://www.joomshaper.com/documentation/joomla-templates/dylan/how-to-customization-tips