Checkout cart CSS problem

-- url of the page with the problem -- : ebm.gminor.at/index.php/de/store
-- HikaShop version -- : 2.3.4
-- Joomla version -- : 3.2.5
-- PHP version -- : 5.5.19

I have a problem with css styling of the last step of the checkout out process. how to get grid of the white background color in the checkout cart?

I have to make the background completely clear because i use "mighty sites" and i share the shop between two sites with different templates.

ebm.gminor.at/

thank you!

Now the link works!