I need a set of polished HTML / CSS mockups that illustrate an e-commerce interface end-to-end. Everything can run with pure markup, CSS3 (Flexbox & Grid), and the lightest touch of vanilla JavaScript only where motion is essential. No frameworks this time—clean, hand-rolled code that I can later wire into a React build. Deliverables • A modern, responsive header that collapses smoothly from desktop to mobile. It includes a logo area, a basic search input (no autocomplete or filtering logic yet, just the proper form markup), and a live-look cart indicator placeholder. • A CSS-only hero carousel able to cycle through three promo banners. Radio-button or keyframe techniques are fine so long as it degrades gracefully when JavaScript is disabled. • Product grid: card layout with price, title, star rating UI, and a clearly styled “Best Seller” badge option. Please keep discount or new-arrival labels in the stylesheet as optional classes but do not surface them in the demo. • Product detail section showing a large image, description, price, and prominent add-to-cart CTA. • Visual sidebar that demonstrates filter and sort controls—checkboxes, sliders, and dropdowns may be static, they just need to look functional. • All components must be built with semantic HTML5, proper ARIA roles, skip links, and visible focus states so the demo is fully keyboard-navigable. Acceptance criteria 1. Pages validate with W3C. 2. No Lighthouse accessibility issues of “serious” or higher. 3. Styles load in under 50 KB unminified. 4. Works flawlessly from 320 px width up to 1440 px. Provide the finished HTML, a single CSS file, and any asset placeholders (SVGs or royalty-free images). Let me know your timeline and, if relevant, any prior samples that show similar front-end craftsmanship.