Creating Column Chart with custom color coding

Hi experts,

I want to create a chart in the case entity to show the number of logged phone calls for each customer.

On the x-axis I want to display the account (customer)

On the y-axis I want to display the number of phone call activities with the following conditions 

     - Between 0 - 5 phone calls in the past 90 days (color the column green)

     - Between 6 - 10 phone calls in the in the past 90 days (color the column orange)

     - Greater than 10 phone calls in the past 90 days (color the column red)

How can I create this chart?

Thanks,

Jon