Change color in binary game

Change the color of the text in the binary game to a dark shade of red when in binary.

src/components/BinaryNumberGame.tsx

@@ -134,7 +134,7 @@ const BinaryNumberGame = () => {
         <Card className="bg-primary/10 border-primary/20">
           <CardContent className="p-6 text-center">
             <h3 className="text-lg font-semibold text-muted-foreground mb-2">Target Sum</h3>
-            <div className="text-4xl font-bold text-primary">
+            <div className={`text-4xl font-bold ${isGameWon ? "text-red-800" : "text-primary"}`}>
               {!hasGameStarted ? "🎯" : isGameWon ? targetNumber.toString(2) : targetNumber}
             </div>
           </CardContent>