Show HN: BraiNOTES, handwritten notes on your lecture PDFs in a browser tab

BraiNOTES is an open-source browser-based note-taking app designed for lectures that allows users to write handwritten notes with various pen styles alongside PDF slides. The application runs entirely in the browser with no accounts or servers required, offering features like multiple paper types, PDF annotation, shape tools, and offline functionality, with all data stored locally in IndexedDB. It can export notes to PDF with vector ink preservation and supports keyboard shortcuts for efficient note-taking workflows.