I need a brand-new, fully responsive company portfolio site built from scratch with HTML5, CSS3 and JavaScript. Besides showcasing our services and projects, the site must include three e-commerce style features I have specifically requested: • secure user account creation • a working shopping cart flow • payment gateway integration (sandbox tested) Clean, modern UI, smooth animations and cross-browser compatibility are important. Please organise the code so it is easy for my in-house team to maintain, and provide a short deployment guide once everything is complete. Deliverables will be the complete source code, all assets and a brief read-me confirming that account creation, cart operations and the payment gateway have been tested end-to-end.