Flashcard Subscription Platform Development

I am looking for an experienced full-stack developer or a team to help build an online platform that provides flashcard decks for clients. The platform will operate on a subscription model, offering monthly and annual plans. The platform must allow users to create accounts and log in to their personal dashboards. There will be two types of users: Administrators, who can create and edit decks, and Normal Users, who can only access and study the available decks. Normal users cannot create or edit flashcards, but they can study the provided decks. User progress must be securely stored, allowing them to resume exactly where they left off when they log in again. There should also be an option for users to reset their progress, either for a specific deck or all decks. The platform will require an integrated payment gateway, enabling users to subscribe to plans. Subscriptions must be tied to the user's account, providing access only to those with an active subscription. Administrators must be able to create and upload flashcard decks, which will be made available to normal users. Each deck will consist of multiple cards, with a question on the front and an answer on the back, similar to Anki’s functionality. Users will study one card at a time using a spaced repetition algorithm, which determines the frequency of reviews based on their performance. There will be different types of cards, such as Basic, Cloze, Cloze-Sequenced, and Image Occlusion. Each card type will include general fields like Category, Question, Answer, Comment, CommentImage, and Source, along with unique fields specific to their type. The platform must implement a spaced repetition algorithm, similar to Anki, to determine when users should review each flashcard. User progress, including performance ratings and review history, must be saved to calculate future study sessions. The user dashboard must be easy to navigate, allowing normal users to browse available flashcard decks organized in a Deck Tree format, with topics and subtopics leading to the desired deck. When a deck is selected, the study session begins, displaying one card at a time. Users will see the front of the card with a “Show Answer” button. After viewing the answer, they will rate their knowledge using options such as Wrong, Hard, Normal, and Easy, which feed into the spaced repetition algorithm. Administrators will have a separate interface for managing the platform. They must be able to create, edit, and organize decks, manage subscriptions, and upload decks for normal users to study. The recommended technology stack includes React (or a similar frontend framework), Node.js with Express for the backend, and MongoDB (or another suitable database). The platform must integrate a payment system, such as Stripe or PayPal, and use secure authentication protocols like JWT or OAuth2. Additionally, the platform must be fully responsive, enabling users to access it via mobile devices. Users must also be able to sync their progress across devices by logging into their account. The platform should include options to reset progress and provide simple statistics, such as the number of cards studied per day. This project requires a highly skilled developer or team with experience in building robust and user-friendly web platforms. If you’re interested, please contact me with examples of previous work and your approach to building this platform. The platform should feature a minimalist design, focusing on simplicity and ease of use. Basic statistics should be available, such as the number of cards studied per day and overall progress. Include basic statistics such as the number of cards studied per day and overall progress. The platform must include a custom-designed user interface, tailored to our specific branding and usability requirements. The custom-designed user interface should follow our existing brand guidelines. The platform should provide basic usage statistics such as the number of cards studied per day and overall progress in a minimalist format.