Changing Field Background Color with dependancies

Wow!   Those Parenthesis are tricky little buggers, aren't they?  Thanks for all your help!  :-)

(function (){

var Red10=this.getField ("Red10").value;

var N36=this.getField ("N36").value;

var N37=this.getField ("N37").value;

var P28=this.getField ("P28").value;

var L30=this.getField("L30").value;

if (((P28)>=(N36))

&&

((P28)<=(N37))

&&

((Red10)>=(L30)))

event.target.fillColor=color.yellow;

else

event.target.fillColor=color.white;

})();