How can I change the color of negative bubble in bubble chart

[Guest]

I find it impossible to change the color of negative bubble into any color
other than the default white.
Could anyone tell me how to change, or it is not changable?
Thanks!

 

[Jon Peltier]

Double click on the series, on the Patterns tab, click Fill Effects, on the
Gradient tab, choose the Two Colors option, then select what you want for
color 2 (color 1 is what you already selected for the series color). Click
OK, then on the Patterns tab, select again the color you want for the
positive bubbles (wiping out the gradient in the Sample box). Click OK.

- Jon