Gradient Conditional Formatting on Scatter Chart

I have a problem trying to get gradient conditional formatting colours onto a scatter chart.
The scatter chart has been generating using X and Y seat co-ordinates, and the idea is to create a heat map based on the popularity of each point. I have done this for column C, but can't figure out a way to transfer this over to the chart.

I have tried researching, but as far as I am aware i can't transfer over conditional formatting rules to other cells or in the chart.

I have attached my current spreadsheet. I am by not an expert in Excel, so any help would be greatly appreciated.