Change the appearance of subgroups in group hierarchy

Hello all. I have 4 main groups and i have created 9 subgroups for each one with the bp group hierarchy plugin. What i want to change it this: when i click on the + sign to show the subgroups i want them to appear in another way. Now, by default they appear as a list one below the other. I want to show for example 3 subgroups at each row. I am trying to change the tree-loop.php and the bp_has_groups_hierarchy() from the extension.php but i can’t find a solution. Thanks in advance for any answer.

https://wordpress.org/plugins/bp-group-hierarchy/