Do further command.
And use a gradient on it.

FX Layer illustration



FX Layer illustration

Select another area ? this time on the bottom.

FX Layer illustration

Further this one too let's say it will be 40 this time.

FX Layer illustration
  




FX Layer illustration

And fill it with the same WHITE to Transparency Gradient.

FX Layer illustration

And in the end we get something like this.

FX Layer illustration