yesterday i wanted to style each image attached to a TreeNode - the TreeNode.ImageUrl picture and not the [+] / [-] buttons
the tricky part was that the open/close buttons have exaclty the same graph as the treenode picture ... !
by looking at the HTML you see that:
td a img { width:50px; height:50px; }
won't do
i noticed that the difference between the two, was the tabindex, thus resulting in this selector:
td a[tabindex~="-1"] img { width:50px; height:50px; }