Motif theme: dividing subnavigation over multiple columns

Hi there,

I am using the Motif theme and one of the main navigation items of my site has quite some subpages with pretty long pagetitles (I must admit). As a result the mouse over submenu is very long as you can see on https://nieuwesitebtm.nl, please select Projecten (projects).

I was wondering if it is possible to divide this submenu over, for example, 2 or 3 columns, each containing 4 or 5 items. To get an impression you can check https://www.zalando.nl/heren-home/, select ‘Kleding’ (clothes) for an example menu.

Hopefully someone can help me with this one.

Many thanks. Martijn