REMOVE COLOURING from the boxes in product listing

Hi

Ive seen mention of how you change the colour of the boxes in for instance the product listing screen (by using the option inside the backend of hikeshop. But Ive not seen mention how you remove the fill here (see below) re the css Im trying to remove, I want the box to be transparent you see:

#hikashop_category_information_menu_50 div.hikashop_subcontainer {
background: none repeat scroll 0 0 #FFFFFF;

Has anyone else managed to find where the colour of the hikashop_subcontainer can be set?

Kate