The official guide gave an example app to explain this https://github.com/vercel-labs/nextgram/tree/main . I want to know when we click on the link from page.tsx of the root folder, why this https://github.com/vercel-labs/nextgram/blob/main/app/%40modal/(.)photos/%5Bid%5D/modal.tsx opens but not https://github.com/vercel-labs/nextgram/tree/main/app/photos/%5Bid%5D ? I see on click the url to the browser gets changed. And when I refresh then https://github.com/vercel-labs/nextgram/tree/main/app/photos/%5Bid%5D page opens and modal goes away.