Hello,
I just had a look on your website, and fist point, you have HikaShop.Css file and so, some Css on elements you spoke earlier.
But of course, maybe you have to add some Css order, but in your Car.css, see
this tutorial
to see how to proceed.
Plus, you can have some Css references,
here
in order to discover some Css order in order to help you.
You have to keep in mind, that HikaSHop have of course some Css In order to organize elements.
For the more specific point on the add to cart button (in product page) is on below, is just a choice.
Anyway, if you want have this button just beside +/- just add this Css code :
div#hikashop_product_Mshblck0235ita_page table {
display: inline;
}
This one, is just an help I guess you have more to add, but of course this
forum aim isn't to provide several line code, but we can guide you.
Regards