The app currently has limited numbers of clothing 'layers', body - underwear - base clothing - middle layer - and outer layer. Every layer has strict thickness rules to prevent clipping on the edges as much as possible. Both tights and leggings are placed in the same underwear layer, but the rules is any accessories will appear over other clothing items with the same layer level. That's why we also added yoga pants, which has almost similar appearance but placed in the base clothing layer, and therefore can be used for replacement for this case.