Hi there,
its because of this CSS:
#menu-main-menu-1 li{
height: 65px;
text-align: right !important;
}
#menu-main-menu-1 > li:nth-child(2) > a:nth-child(1){
height: 65px;
}
if you swap height: 65px;
for line-height: 65px;
then the text will be vertically centred within the menu item.