Product Listing Background Grey Colour

on my product listing page, each product has a grey background behind. can i know how to change it to white?

I only manage to change it to white in the categories listing page..

You need to go to Display->Content modules and edit your menu's associated module options and change the color there.

hi,

I changed the colour to the only published module. but the colour on front end for individual products are still not changed. the categories are white, but not the products.

Please do it for the unpublished modules as well.
When a module is used as an associated module, it is not published in joomla but in the "associated modules" option of your menu's hikashop options.