This is awesome! Although Firefox seems to ignore media queries that don't have a medium type (just using `@media all and (max-...) { .. }` fixes that though),

This is awesome! Although Firefox seems to ignore media queries that don't have a medium type (just using `@media all and (max-...) { .. }` fixes that though), and using the prefix search of `a[id^="up_"]` is probably more efficient than the full substring search of `id*="up_"`.