If you want to resize buttons and move them anywhere in the design, this can be done with the 'free menu' style.  Horizontal bar and vertical menus do not permit the same sizing flexibility, refer to other articles about the capabilities of these styles

To switch on the free menu style 
1)  Use the 'free menu' style  in the style->menu  settings, note that the 'highlight buttons' switch is on, this looks good with the free menu. It is not applicable to the vertical menus.  

Setting the free menu style

2)  Then for example, to change the size of the Gallery4 button in the gallery editor  (F -> Portfolio -> Elements -> Gallery4

Changing the size of a menu button