Sorry about that, I wasn’t clear earlier.
I mean that the children would have a fixed size and the number of columns would vary depending on the width of the viewport.
For example, with a fixed child of 300px width, there would be 3 columns in a 1024px width viewport. This would shrink to 2 columns if the viewport was say, 800px. And on a 400px cellphone, only one column would be present.
