Modern Vue.js E-Commerce Front-End -- 2

I’m putting together a sleek, modern storefront and need the entire customer-facing layer built with Vue.js 2, HTML5, CSS3 and vanilla JavaScript, bundled through Gulp.js. The back-end endpoints for products and user accounts are already in place; your job is to consume them and craft a responsive experience that feels equally at home on mobile and desktop.

Core screens and flows
• Home page that fetches and displays the full product catalogue.
• Product detail view with image gallery, description and price.
• Persistent shopping cart with quantity controls and live totals.
• Authentication flow (register, login, logout) wired to the existing user API.
• Checkout that connects to our Payment Gateway API and supports credit/debit cards, PayPal and bank transfer.

A clean, modern aesthetic is essential—think ample white space, crisp typography and smooth transitions—while keeping the codebase modular and well commented so future team members can jump in without a learning curve.

Deliverables
1. Complete front-end source code organised by feature and committed to Git.
2. Clear comments, README and any build scripts needed to run `gulp` and start the dev server.
3. A short PDF or Markdown guide with screenshots of each finished page and notes on API endpoints used.

Hand-off is finished when I can `npm install`, `gulp`, point the app at my staging API, and run through a full browse-to-checkout path on both desktop and mobile without glitches.