I try to make `UICollectionView` with cells, that intersect and partially overlay each other as it is done at screenshot:
![Layout 1](https://i.stack.imgur.com/rSCPJ.png)
This layout was reached by setting

```
self.minimumLineSpacing = -100;

```

at my `UICollectionViewFlowLayout` subclass.
When I scroll down, everything is OK. I see what I want. But when I scroll up, I see another behaviour, not like I expected:
![Layout 2](https://i.stack.imgur.com/NkIbW.png)
So my question is: how can I make my layout look as at the first screen regardless scroll view direction. 
**Note**: I have to support both iOS 6 and 7.

Thanks very much for any advices and any help.