Charting colors

[WxShady13]

I have a Pivot Table that contains 3 columns. Column A is the date that the data applies to (10/28/2018, etc.). Column B is the individual category the data applies to (<6 Mo, >6 Mo <12 Mo, etc.). Column 3 contains the individual amounts that apply to that category, based on that date (.0030%, etc.). I need the colors to match by Category as more data is added every week. Currently I have the Pivot Chart to show Date and then Category so that the bottom axis is grouped by Category which is then grouped by date. How can I keep that grouping but ensure that each Category is the same color as the matching category regardless of date?