Because we have to account for screen sizes, zoom levels, text sizes, and other things, it's usually best to use a built-in class from the `tile--c` family to determine gridview widths.  We still need to flesh out all of the available sizes.  Your initial size in row view you can continue to specify in the spice css, but you should only use a single selector (so `.tile--google_plus` instead of `.zci--google_plus .tile--google_plus` - this allows the width control class to do its job correctly. :)