The main menu is configured as Megamenu, and a menu of categories is a normal block with accordion. Change the output categories. Set up the display of the second level of the main menu and in the file avtoservis-minsk.by/catalog/view/theme/beamstore/c...
comment out line 253 .responsive .box-with-categories
I would in any case have added to the index in the line 343
the adaptability of the class hidden-xs