OK,
you have a line of code in the actual source of the page
#hikashop_category_information_module_43 div.hikashop_container {
margin: 0;
}
This is a style which is overriding the styles in the attached css pages.
@Nicolas - Perhaps Nicolas could let us know how or where the css comes from that gets injected into the actual page source. Im not sure where that comes from.
If you want though, in the mean time, you can open your frontend_default.css file and put the below style at the bottom of the style sheet.
.hikashop_module .hikashop_container {
margin: 10px !important;
}
if you need help with where or how to open the frontend_default.css file refer to this documentation (
This is not perfect though as you shouldn't use the !important tag too much. Rather find out where that original css style is created from and change or remove that.