Selecting multiple sub elements at once

Question

So I am trying to write a Stylish style to remove the black background of avatars on a forum I frequent (they put a black background so transparencies are black instead of white so stand out from the forum, which I dislike).

By copying the selector with the Chrome inspect tool I have isolated the needed argument to this

#mainpostcontent > table > tbody > tr > td > table.forumline > tbody > tr:nth-child(XX) > td:nth-child(1) > span > table > tbody > tr > td {
    background: none !important;
}

Where the XX above is a number. Since the numbering changes whether a user has an avatar or not, I have to saturate the style with about 200 individial lines like so

#mainpostcontent > table > tbody > tr > td > table.forumline > tbody > tr:nth-child(1) > td:nth-child(1) > span > table > tbody > tr > td {
    background: none !important;
}
#mainpostcontent > table > tbody > tr > td > table.forumline > tbody > tr:nth-child(2) > td:nth-child(1) > span > table > tbody > tr > td {
    background: none !important;
}
#mainpostcontent > table > tbody > tr > td > table.forumline > tbody > tr:nth-child(3) > td:nth-child(1) > span > table > tbody > tr > td {
    background: none !important;
}

and so on.

Is there a way I can select all of these with a single selector or is it a limitation of CSS that prevents me wildcarding the first tr:nth-child(2) entry?

Edit: I can't find the accept answer button, this was the answer: "Could you just remove the nth-child argument of > tr:nth-child(3) > so that it becomes > tr >? – S. Walker"

Answer 1

it makes more sense to add a class or id to the element for which you want to alter the styles. anyway upload your html for better understanding of the problem