fix: title text under logo on mobile devices

Author: danieldanielecki

components/TopNav.tsx

@@ -39,7 +39,7 @@ const TopNav = () => {
           height={50}
           width={200}
         />
-        <p className={`windowWidth < 640 ? "text-md" : "text-lg"`}>
+        <p className={`${windowWidth < 768 ? "text-sm" : "text-xl"}`}>
           🧪 Practice Exams Platform
         </p>
       </div>