Any way of coding this?

[Moh]

Well the sides of the boxes are curved, so i don't know how to do this

[Knuxxy]

Yes.
Code 3 different designs and apply them to each page accordingly to the sizes of the content boxes.
Otherwise, no.

[Jxhn]

You'll probably need to use javascript if the boxes aren't fixed height.

Another thing you'll need to consider is what to do if the difference in height is less than the height of 2 of the curves

[Meti]

I don't really understand?
Make different containers for each sides?