What you require is switching the position of the elements on your home page.
This cannot be done using Custom CSS.
It requires modification of theme code, which is not covered in our support scope.
You can contact our developer for this customization.
Lowering and Switching position has entire different meaning.
when you lower an element, it pushes down all elements underneath it.
You will have to rebuilt your homepage using content box shortcodes in a static homepage.