I'm struggling with Haskell programming. 

I've got the list below and I want to make it stack on each other, so it'd be like 3 x 4 pixel image. eg:

![pixel image](https://imgur.com/78GPr.png)

and how can I change the value of the first row or second ...
eg: say like I want to make it darker or whiter (0 represents black and 255 represents white)

```
type Pixel = Int
type Row = [Pixel]
type PixelImage = [Row]
print :: PixelImage 
print = [[208,152,240,29],[0,112,255,59],[76,185,0,152]]

```

The code I've got here does not stack the list and I don't know how to stack it.

Please help, I'm really struggling with this.

Thanks in advance!