- Move index.html → templates/index.html (Jinja2, uses url_for) - Extract CSS → static/css/app.css - Split JS into static/js/: utils.js, dashboard.js, shares.js, quotas.js, users.js, main.js - Switch app.py from send_file to render_template Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>