Development of a Question Purchase & Download System for teachers and students, including:

Teacher account management with manual validation by an administrator.

Credit-based payment system via MercadoPago (1 credit = 1 question).

Advanced search with filters: level, difficulty, subject, region, source, year, etc.

Protected question display (anti-copy, right-click blocking, text selection disabled).

Full LaTeX formula rendering with MathJax.

Bulk downloads (Word & LaTeX) with cart and history.

Centralized admin panel: accounts, credits, downloads, database management.

Support for enriched questions (images, formatted solutions, metadata).

Automatic email delivery of purchased questions.