Drop down Menu - change of colour

I was wondering if this was possible. I have a drop down menu with say, 10 choices. When I make a choice from the list, I want the colour of the cell to change.

I know it is possible to do conditional formatting upto 3 conditions. while my question is that I have 10 choices and whatever I select I want it to change to just one colour. The conditional formattins is asking for cell values and I can choose only upto three values.

Any clues ?