Colour 7 Cells In A Row And Then Switch Colour?

So I have a macro that colors the selected cells in a certain color. Now im looking for a code that will switch that color every 7th cell, the cells will only be selected horizontally. For example:

if the selected range is 10 cells, 7 of them should be in one color and 3 of the should be in another. But if the selected range is 15 cells the first 7 should have one color and the next 7 should have another and then the last one should have the first color again, and so on..