CSS Selectors - Selecting a specific child element

Answer 1

If you have the ability to change the output of the shopping cart, you could add a class to the <tr> tag, e.g. <tr class="row01">, <tr class="row02">, etc.

If you can't change your back-end, then it's a choice of front-end tech. The most cross-browser method is to use jQuery to apply the row classes. The other alternative, CSS3, isn't supported by any current IE; given that this is a shopping cart, you're probably interested in the widest level of browser support.

Something like:

$('#shopping-cart-totals-table tr').each(function(n){
    $(this).addClass('row'+n);
});

Alternatively, if you're only interested in the third item, use jQuery in the same way as CSS3:

$('#shopping-cart-totals-table tr:nth-child(2) .price').addClass('highlightClass');

Answer 2

With CSS3's :nth-child() it's easy to fulfill the "specific" criterion:

#shopping-cart-totals-table > tbody > tr:nth-child(2) > td:nth-child(2) .price

Or, an alternative that works more in favor of browser compatibility (does not use CSS3 selectors, assumes exactly two trs and two tds):

#shopping-cart-totals-table > tbody > tr + tr > td + td .price