Change product page layout

Hi all,

I would like to change the product page layout within Woocommerce. Instead of appearing in the right column, I want the woocommerce product tabs to appear full width, just before the row with related products.

Here’s the picture of what I want:

https://i786.photobucket.com/albums/yy142/exelletor/producttabs_zps77276be8.jpg

(the upper image shows the current situation, the lower shows what I would like to achieve)

Website accessible via https://brainwavzstore.biz.ht

Thanks in advance. ??