The Divs should fit into a parent Div:      With 1 Div, the Div has a width of 100%

                                                                With 2 Divs, they have the width of 50%

                                                                With 3 Divs, they are all 33.333% and so on...

                                                                Together they are always 100%

Its comparable to the tap bar of your Internet Browser: You add new taps and the already existing ones automatically resize so they all fit in the bar. 

Any ideas?

Thanks guys