WooCommerce Product Page css

You’ve actually done most of the work finding this by identifying the classes (good job!). All you then had to do was to grep the WooCommerce code for those two – and you’ll find them both in templates/single-product/product-attributes.php.

So all you need to do to restructure the table is to override the single-product/product-attributes.php template and build the table as you’d like. You’ll need to add this to your theme, or make a child theme, and include the modified version there. From the WooCommerce docs:

(I don’t think it’s possible to restructure the table by CSS alone, since this is an HTML table with one TR per attribute – I think you’ll have to change the HTML. But I may be wrong.)